Dennis-- I've been trying to get some information from JWT regarding the 1990 TCU replacements they sell but I'm still waiting for an email back and hitman said to shoot a post to you about it.
In past posts we have discussed the tri-mode "manual shifter" abilities where the TCU will allow the driver to override the automatic 1 to 2 shift by placing the shifter in the 1 position. You said that the transmission will hit the rev limiter hard in both the first and second positions, but wouldn't shift beyond the position of the shifter.
What I am trying to find out is whether any of the other TCU's they make will allow for the same "shifter override". It seems that JWT is not making any tri-modes at the moment and I'd like do something about my stock 2nd gear starts but don't want to give up the ability to hold the transmission in 1st or 2nd if I want.
Do you know if the 1st gear start, high rev TCU also allows for manual override (keeping the transmission in 1st if you put the shifter in first)?
Thanks for your help.
Dennis??? TCU Question.
I assumed that to be the case, but read where someone (heavyduty?) had the "non" tri-mode and it disregarded the shifter position. However, he also later mentioned that his was purchased used and may have been tampered with. It appears that must be the case.
Would you recommend then, going with the 1st start, high rpm shift cu in lieu of the tri-mode? If I recall, you have a tri-mode but have left it permanently in the 1st start, power mode... I am assuming that is what he standard cu does???
Thanks for the quick reply by the way.
Would you recommend then, going with the 1st start, high rpm shift cu in lieu of the tri-mode? If I recall, you have a tri-mode but have left it permanently in the 1st start, power mode... I am assuming that is what he standard cu does???
Thanks for the quick reply by the way.
Thanks Dennis. I appreciate your help. I'll give JWT a call tomorrow and see if I can get some clarification.
Wes, in the post I'm referencing, heavyduty was talking about "holding" a gear based upon selector placement. We spent a good deal of time batting the "verbiage" around, but ultimately we were on the same page. Basically I want the same functions from a shifter standpoint that I get with the stock TCU, but with first gear starts and "power mode" or higher rpm shifts.
Never really thought about using the 94 TCU... I wasn't sure it was compatible. Who do you know that has done it?
Wes, in the post I'm referencing, heavyduty was talking about "holding" a gear based upon selector placement. We spent a good deal of time batting the "verbiage" around, but ultimately we were on the same page. Basically I want the same functions from a shifter standpoint that I get with the stock TCU, but with first gear starts and "power mode" or higher rpm shifts.
Never really thought about using the 94 TCU... I wasn't sure it was compatible. Who do you know that has done it?
I've heard various views on using the later TCU in the 90 and it always seems to come back to the fact that the gearing in the 94-95 is different, thus the TCU allows for it.
I drove Hitman's 94/95 with 4.08 rear end and it felt pretty darn close to my stock 90. In fact it was hard to tell much difference although it "seemed" that when I put the gear selector in 1st, my 90 redlined quicker... but I didn't do any kind of side to side comparison. Just pounded the pedal in his and then got into mine and put the shifter in 1st and tried to remember how his acted. So they may be neck in neck, but the fact that the rear end gearing had to change to make the 94 feel that way, begs the question as to whether the TCUs are the same because the transmission ratios certainly aren't.
Also, since I'm doing both the JWT ECU and TCU I would assume that they would work in tandum to provide optimal performance. I just need to decide on which one.
I drove Hitman's 94/95 with 4.08 rear end and it felt pretty darn close to my stock 90. In fact it was hard to tell much difference although it "seemed" that when I put the gear selector in 1st, my 90 redlined quicker... but I didn't do any kind of side to side comparison. Just pounded the pedal in his and then got into mine and put the shifter in 1st and tried to remember how his acted. So they may be neck in neck, but the fact that the rear end gearing had to change to make the 94 feel that way, begs the question as to whether the TCUs are the same because the transmission ratios certainly aren't.
Also, since I'm doing both the JWT ECU and TCU I would assume that they would work in tandum to provide optimal performance. I just need to decide on which one.
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HeavyDuty
- Posts: 1281
- Joined: Tue Sep 23, 2003 4:51 pm
- Car: 1995 Infiniti Q45
95 Nissan 240SX S14
96 Nissan D21
06 Nissan 350Z Z33
My 1st start, high shift program, (non-tri) will shift itself from 1-2, even if in 1st gear on the selector, and not necessarily at redline. Even on moderate acceleration from a stop, it shifts to 2nd when it feels like it, selector in 1st.
My ECUw/100shot & TCU was purchased from JWT new. The *used* part was that I purchased a junkyard ECU/TCU to send in for the upgrade rather than sending in my units from my car.
I never could get a good answer from Ben Pila @ JWT whether the 1st start only program, or 1st start only (no hi shift) on a tri mode acted any differently. I'm not sure if he understood my question. These cars are getting old, and the idiodsyncrasies are fading from memory a bit, I'm sure.
Clark Steppler (the programmer) could answer the question, but he is only available via e-mail from *within* JWT. No way for an 'outsider' to communicate with him unless you request a call, but don't bet on it. If he answered every inquiry, he could do nothing else.
My ECUw/100shot & TCU was purchased from JWT new. The *used* part was that I purchased a junkyard ECU/TCU to send in for the upgrade rather than sending in my units from my car.
I never could get a good answer from Ben Pila @ JWT whether the 1st start only program, or 1st start only (no hi shift) on a tri mode acted any differently. I'm not sure if he understood my question. These cars are getting old, and the idiodsyncrasies are fading from memory a bit, I'm sure.
Clark Steppler (the programmer) could answer the question, but he is only available via e-mail from *within* JWT. No way for an 'outsider' to communicate with him unless you request a call, but don't bet on it. If he answered every inquiry, he could do nothing else.
Gotcha HD. I remembered that you had "something" w/the TCU that was used, but couldn't remember what it was. But at least I had the facts right. I'm doing the same thing-- used ECU/TCU rather than having the car down while I wait... especially since Hitman was told that there was an 8-10 week delay on the ECU and the tri-mode TCU was on "hold" (whatever that means).
I'm sure your right about the 14 year old cars starting to fade. Doubtful that there are that many (comparatively speaking) running around these days requesting $600 CU mods. But there are us NICO boys... so hopefully they won't blow off the product altogether.
The DEFINITIVE answer on the tri-mode came from Dennis when he confirmed that his personal TCU will hold the gear the selector is in. Problem is getting one. If your first start, hi rev won't hold, then something is either awry with THAT unit or the program ignores selector position on all of them.
Do you know what the difference is between the Web listings for the "A/S" version vs. the "BAS" version? JWT could be more helpful with the descriptions.
I'm sure your right about the 14 year old cars starting to fade. Doubtful that there are that many (comparatively speaking) running around these days requesting $600 CU mods. But there are us NICO boys... so hopefully they won't blow off the product altogether.
The DEFINITIVE answer on the tri-mode came from Dennis when he confirmed that his personal TCU will hold the gear the selector is in. Problem is getting one. If your first start, hi rev won't hold, then something is either awry with THAT unit or the program ignores selector position on all of them.
Do you know what the difference is between the Web listings for the "A/S" version vs. the "BAS" version? JWT could be more helpful with the descriptions.
I am using the JWT ECU with my 95 TCU and I can not tell a difference in shift points. I can not get my car into the redline zone.
I have no problems with a 95 YCU working with my 92 transmission and my 92 transmission working in my 95 car....if that makes any sense. I also have a 93 TCU with the infamous 1st gear start...no difference that I can tell between the 93 TCU and 95 TCU. I ask Dennis this question...and he did say that the TCU does monitor engine RPM in some way or another, but that it was only as a secondary function. My initial thoughts are that the secondary monitoring of the RPMs is causing the TCU to shift....even with the JWT ECU.
Only a few runs at the track will tell the true difference between running a 95 vs. 93 TCU on a 92 transmission.
The JWT ECU took exactly 4 weeks for me and I ordered my ECU from Stillen. I got it for $605 with a core exchange program which is a much better deal than what JWT was willing to give me. Ask for Ken or Kenny at Stillen sales and tell him I sent you...he should be able to hook you up as he did me since I bought about $1,750 of parts from him. I am in no way affliated or will receive any benefits from Stillen or Ken as I have bought already every part that I will ever need from Stillen for my Q...seriously. My JWT ECU appears to have come straight from JWT as the instructions, labeling, and stamp on the ECU cover all say JWT. No reference to STillen at all. Even the shipping return address for my core exhange was straight to JWT. I did a core exhange $500 that they charge you when they actually send you the JWT ECU....you have 2 weeks to send back your original ECU to avoid the core charge of $500.
The TCU trimode is on hold. See my posts a month ago about this as JWT called me to say that the trimode would probably be no longer available.
http://www.nissaninfiniticlub....imode
The deal with the trimode is that the trimode is programed into a special computer chip that is only available in Japan and they can not find anymore of them currently. When I last spoke with Ben about 2 weeks ago....they were still searching for the trimode chip with several different suppliers in Japan but not having much luck as the chip apparently is not being made anymore. They think it is possibly being sold on the black market, but at what cost to them they told me and they rarely see any demand to purchase such a chip anymore as it is only used specifically for the Q45 is what they told me. I am on the wait list just incase they get their hands on the trimode chip, but I do not think that it is likely that they will get them from the sound of Bens voice. This will probably be the ultimate last opportunity to purchase a trimode chip, so if anybody is interested at all..then now is probably the time since they told me that they rarely get any demand for these.
BTW....JWT told me that they have plenty of the other mode of chips ready to go as this is just a reprogram of the current TCU. I am going to get the regular JWT TCU if they do not find the chips within the next month. I already have an OEM 93 TCU with 1st gear starts and also my original 95 TCU...so the JWT TCU would be a nice benefit and I can switch it to the 93 OEM TCU if I do not like the JWT for some reason easily enough.
I have no problems with a 95 YCU working with my 92 transmission and my 92 transmission working in my 95 car....if that makes any sense. I also have a 93 TCU with the infamous 1st gear start...no difference that I can tell between the 93 TCU and 95 TCU. I ask Dennis this question...and he did say that the TCU does monitor engine RPM in some way or another, but that it was only as a secondary function. My initial thoughts are that the secondary monitoring of the RPMs is causing the TCU to shift....even with the JWT ECU.
Only a few runs at the track will tell the true difference between running a 95 vs. 93 TCU on a 92 transmission.
The JWT ECU took exactly 4 weeks for me and I ordered my ECU from Stillen. I got it for $605 with a core exchange program which is a much better deal than what JWT was willing to give me. Ask for Ken or Kenny at Stillen sales and tell him I sent you...he should be able to hook you up as he did me since I bought about $1,750 of parts from him. I am in no way affliated or will receive any benefits from Stillen or Ken as I have bought already every part that I will ever need from Stillen for my Q...seriously. My JWT ECU appears to have come straight from JWT as the instructions, labeling, and stamp on the ECU cover all say JWT. No reference to STillen at all. Even the shipping return address for my core exhange was straight to JWT. I did a core exhange $500 that they charge you when they actually send you the JWT ECU....you have 2 weeks to send back your original ECU to avoid the core charge of $500.
The TCU trimode is on hold. See my posts a month ago about this as JWT called me to say that the trimode would probably be no longer available.
http://www.nissaninfiniticlub....imode
The deal with the trimode is that the trimode is programed into a special computer chip that is only available in Japan and they can not find anymore of them currently. When I last spoke with Ben about 2 weeks ago....they were still searching for the trimode chip with several different suppliers in Japan but not having much luck as the chip apparently is not being made anymore. They think it is possibly being sold on the black market, but at what cost to them they told me and they rarely see any demand to purchase such a chip anymore as it is only used specifically for the Q45 is what they told me. I am on the wait list just incase they get their hands on the trimode chip, but I do not think that it is likely that they will get them from the sound of Bens voice. This will probably be the ultimate last opportunity to purchase a trimode chip, so if anybody is interested at all..then now is probably the time since they told me that they rarely get any demand for these.
BTW....JWT told me that they have plenty of the other mode of chips ready to go as this is just a reprogram of the current TCU. I am going to get the regular JWT TCU if they do not find the chips within the next month. I already have an OEM 93 TCU with 1st gear starts and also my original 95 TCU...so the JWT TCU would be a nice benefit and I can switch it to the 93 OEM TCU if I do not like the JWT for some reason easily enough.
http://www.nissaninfiniticlub....61322
scroll down through the first couple of posts and you will see some info from Dennis about using the different TCU and differet transmission....also my own personal experience as well.
I did notice a difference running a 93 TCU against my 95 transmission, but I can not tell a difference running a 932 transmission with my 95 TCU.
Also scroll to the end of the posts where Dennis talks about the JWT ECU as it surpised me a little to find out that it really only works above 3,000rpms and at only 80%+ throttle. I had already observed this with my JWT ECU and he confirmed my thoughts/experience....as I would have thought that I would have felt a difference under normal driving conditions.
I can tell you that when my car shifts at WOT I now feel a stronger shift than I did before so I now know what an extra 20HP feels like at 6,900 rpms and also the need for the JWT TCU.
BTW...Just in case you are wondering about the why I am buying my JWT TCU with JWT vs. Stillen since Stillen gave me a much better deal is that I got the same price and thought that I would try JWT for a change.
scroll down through the first couple of posts and you will see some info from Dennis about using the different TCU and differet transmission....also my own personal experience as well.
I did notice a difference running a 93 TCU against my 95 transmission, but I can not tell a difference running a 932 transmission with my 95 TCU.
Also scroll to the end of the posts where Dennis talks about the JWT ECU as it surpised me a little to find out that it really only works above 3,000rpms and at only 80%+ throttle. I had already observed this with my JWT ECU and he confirmed my thoughts/experience....as I would have thought that I would have felt a difference under normal driving conditions.
I can tell you that when my car shifts at WOT I now feel a stronger shift than I did before so I now know what an extra 20HP feels like at 6,900 rpms and also the need for the JWT TCU.
BTW...Just in case you are wondering about the why I am buying my JWT TCU with JWT vs. Stillen since Stillen gave me a much better deal is that I got the same price and thought that I would try JWT for a change.
BTW... I had a loooong reply typed and when I went to submit it, the site was down and it bit the cyberdust.
Anyway, the jist of it was that I found your threads and experiences interesting. I actually received a reply to an email I sent over the weekend to JWT from Ben Pila. He basically told me that there was no difference between the tri-mode in the 1st start, hi rev/power mode and the basic TCU with 1st start, hi rev/power.
But, I needed details so I picked up the phone this morning and called Jim Wolf Technologies. After asking for Ben... then being put on hold twice as the receptionist tried to find him... Jim picked up the phone. Here is the scoop:
1) Tri-mode is toast. It used a Nissan circuit board that was easily modified to handle the the extra mode circuits, which combined with the eprom burn resulted in a TCU that could "do" more than one thing. You're right... Nissan reengineered the board so now it is NOT easily modified. Jim said that a sister company in Japan can occasionally get some of the original boards for them, but atm they don't have any. He said the only current option is the single mode in either 1st Start/hi rev/power mode (a "sports mode" they call it) or the 1st Start/oem rev which is basically the stock TCU that starts in first gear.
2) Shifting issue: detailed in previous posts in this thread, he said that the single mode TCU will behave just like the tri-mode (set in the 1st Start/hi rev) and that all shift selector positions would be respected identically by both CUs.
3) So why does HD's single mode blow through 1st into 2nd with the selector in first? Jim said that the reason has to do with 4 things; a) Mechanical condition of the transmission, b) ECU used, c) TCU used, and 4) condition of the relative sensors such as the turbine speed sensor. Evidently, when the early Q's were new or newer the TCU or TCU/ECU combination results were static and predictable. However he said as the trannys started to age and enter various different stages of reconditioning (e.g. simple rebuilds to full blown mods like the Level 10) the mechanical variables changed, thus changing the sensor input and thereby changing the way the TCU and the ECU reacted. I guess the TCU shift points were dictated somewhat by when the mechanics of the transmission indicated via sensors that it "should" shift gears. At the same time the ECU is receiving input and determining when to apply the rev limiter. Occasionally these two issues collided and if the shift happened before hitting the rev limiter, it went on into 2nd gear. If the rev limiter was applied first, the transmission stayed in 1st gear.
Apparently it is a function of the rebuild or condition of the transmission and various sensors as much as it is the TCU or ECU. As Dennis has always maintained-- you have to keep all the physical components to spec in order to realize the designed performance of the car and also any mods which were originally created for a FACTORY SPEC'D Q45.
So basically, the best shot at gaining the most from the JWT control units is to have a fresh "stock" rebuild or new transmission, then use both the JWT ECU and TCU while also making sure your speed, crank and other sensors are functioning properly. Any deviation will impute the disclaimer "individual results may vary".
4) Your conclusions on the ECU are also correct. Performance hits at 3,000 rpm+ and it SHOULD rev to 7,200 between shifts (given the above).
It's interesting to cogitate on the affect the your Level 10 rebuild will have on the ECU/TCU programming. When the transmission really "wants" to shift and how the controllers react to the sensory input. It seems the cu's would respect the input and behave accordingly. I may be mistaken, but just because the ECU ALLOWS 7,200 rpm before the rev limiter doesn't necessarily mean the transmission will wait that long before shifting.
I'll be interested to see what happens once you get the JWT TCU installed. In the mean time I think I'm going to trip the trigger on both the ECU and the single mode TCU w/hi rev/power mode (Arizona doesn't get much snow and that is about all the 2nd gear start is good for and the only real advantage to the tri-mode IF we could get one). Heck, at a minimum the TCU starting in 1st gear will help make my $2,700 rebuild last another 125k miles or more (and yeah... I do have a BIG arse cooler installed).
Also thanks for the JWT/Stillen price info... from what I've found, anyone who sells ECU/TCU's for the first gen Q are just gettin 'em from JWT and playing with the price/core terms. JWT should match the reseller price since it won't be a huge diff.
Anyway, the jist of it was that I found your threads and experiences interesting. I actually received a reply to an email I sent over the weekend to JWT from Ben Pila. He basically told me that there was no difference between the tri-mode in the 1st start, hi rev/power mode and the basic TCU with 1st start, hi rev/power.
But, I needed details so I picked up the phone this morning and called Jim Wolf Technologies. After asking for Ben... then being put on hold twice as the receptionist tried to find him... Jim picked up the phone. Here is the scoop:
1) Tri-mode is toast. It used a Nissan circuit board that was easily modified to handle the the extra mode circuits, which combined with the eprom burn resulted in a TCU that could "do" more than one thing. You're right... Nissan reengineered the board so now it is NOT easily modified. Jim said that a sister company in Japan can occasionally get some of the original boards for them, but atm they don't have any. He said the only current option is the single mode in either 1st Start/hi rev/power mode (a "sports mode" they call it) or the 1st Start/oem rev which is basically the stock TCU that starts in first gear.
2) Shifting issue: detailed in previous posts in this thread, he said that the single mode TCU will behave just like the tri-mode (set in the 1st Start/hi rev) and that all shift selector positions would be respected identically by both CUs.
3) So why does HD's single mode blow through 1st into 2nd with the selector in first? Jim said that the reason has to do with 4 things; a) Mechanical condition of the transmission, b) ECU used, c) TCU used, and 4) condition of the relative sensors such as the turbine speed sensor. Evidently, when the early Q's were new or newer the TCU or TCU/ECU combination results were static and predictable. However he said as the trannys started to age and enter various different stages of reconditioning (e.g. simple rebuilds to full blown mods like the Level 10) the mechanical variables changed, thus changing the sensor input and thereby changing the way the TCU and the ECU reacted. I guess the TCU shift points were dictated somewhat by when the mechanics of the transmission indicated via sensors that it "should" shift gears. At the same time the ECU is receiving input and determining when to apply the rev limiter. Occasionally these two issues collided and if the shift happened before hitting the rev limiter, it went on into 2nd gear. If the rev limiter was applied first, the transmission stayed in 1st gear.
Apparently it is a function of the rebuild or condition of the transmission and various sensors as much as it is the TCU or ECU. As Dennis has always maintained-- you have to keep all the physical components to spec in order to realize the designed performance of the car and also any mods which were originally created for a FACTORY SPEC'D Q45.
So basically, the best shot at gaining the most from the JWT control units is to have a fresh "stock" rebuild or new transmission, then use both the JWT ECU and TCU while also making sure your speed, crank and other sensors are functioning properly. Any deviation will impute the disclaimer "individual results may vary".
4) Your conclusions on the ECU are also correct. Performance hits at 3,000 rpm+ and it SHOULD rev to 7,200 between shifts (given the above).
It's interesting to cogitate on the affect the your Level 10 rebuild will have on the ECU/TCU programming. When the transmission really "wants" to shift and how the controllers react to the sensory input. It seems the cu's would respect the input and behave accordingly. I may be mistaken, but just because the ECU ALLOWS 7,200 rpm before the rev limiter doesn't necessarily mean the transmission will wait that long before shifting.
I'll be interested to see what happens once you get the JWT TCU installed. In the mean time I think I'm going to trip the trigger on both the ECU and the single mode TCU w/hi rev/power mode (Arizona doesn't get much snow and that is about all the 2nd gear start is good for and the only real advantage to the tri-mode IF we could get one). Heck, at a minimum the TCU starting in 1st gear will help make my $2,700 rebuild last another 125k miles or more (and yeah... I do have a BIG arse cooler installed).
Also thanks for the JWT/Stillen price info... from what I've found, anyone who sells ECU/TCU's for the first gen Q are just gettin 'em from JWT and playing with the price/core terms. JWT should match the reseller price since it won't be a huge diff.
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HeavyDuty
- Posts: 1281
- Joined: Tue Sep 23, 2003 4:51 pm
- Car: 1995 Infiniti Q45
95 Nissan 240SX S14
96 Nissan D21
06 Nissan 350Z Z33
desertq45 wrote:3) So why does HD's single mode blow through 1st into 2nd with the selector in first? Jim said that the reason has to do with 4 things; a) Mechanical condition of the transmission, b) ECU used, c) TCU used, and 4) condition of the relative sensors such as the turbine speed sensor. Evidently, when the early Q's were new or newer the TCU or TCU/ECU combination results were static and predictable. However he said as the trannys started to age and enter various different stages of reconditioning (e.g. simple rebuilds to full blown mods like the Level 10) the mechanical variables changed, thus changing the sensor input and thereby changing the way the TCU and the ECU reacted.
Interesting, it's hard to get Jim on the phone, and I was having a hard time getting an answer from Ben for the reasons I listed above.
One item to throw in the mix is I didn't follow my own advice & install the junkyard ECU/TCU in my car while sending my original one to JWT. I got in a hurry & sent the junkyard ones to be worked. Now that I think about it, the ECU I received was from a traction car, but Ben said Clark said he could defeat that in the reprogramming & that otherwise the units checked out OK.
The trans was freshly rebuilt, but the OE inline filter behind the radiator was not changed. It's possible I have a blockage there that's causing some funky stuff. Of course everyone thinks "their" transmission guy is good, etc. We've had good results with our upgraded rebuilds, and watching Rswicki's video of his 1-2 shifts, my car is about the same. I guess I was wanting TH350/400, 700R4, 4L60/80E type shifts from my RE4R03. Not gonna happen.
Dennis also mentioned switching to Mobil1 and checking line pressure while driving. I believe in Mobil1, and I'm currently engaged in a cooler install & relocating the inline filter, etc.
Would mine act the way Jim said had I sent in my units instead of the others? Might I have some "dial-in" issues to deal with? We'll see. Hopefully when I get everything in tip top shape, this will go away.
I'm not one to manually shift that often, but if I wanted to hold 1st for whatever reason, I'd like to be able to.
Before my radiator sprung a leak (while engaged in a death match with a Fox 5.0) I also had a bit too much fluid in the trans, too. I drained a little bit & it seemed to be happier, but I haven't had time to re-test the 1st gear hold since then.
It DOES make you think doesn't it? My business is software and I employ several "Clarks" who tell me all the time they can do things with software to make hardware act the way we want. 9/10 times they are successful-- these guys are amazing-- but sometimes, that 1 out of 10 time it goes awry drives the customer (and us) crazy. The thing is, humans are fallible and software is just magnetic or electrically charged "air" suspended in some form of media, which makes it fragile. In this case, an "erasable programmable read only memory" (EPROM) chip. If the "burn" goes well, and all data (charged particles) over-write properly, then the program acts as advertised and the hardware behaves as expected (within that circuitry). There is always the chance that "something" didn't hold... you have a 1 where there should be a 0 in the binary code and it is causing the unwanted behavior. But it is hard to diagnose. By far the easiest way would be to swap in another like TCU w/o t/c and see if the same thing happens (of course you'd have to find one first).
I have no way to really tell how well "my" transmission guy did on my rebuild. I want to believe that it is sufficient, but since they didn't replace every gear/hardware component and blueprint the transmission back to oem spec... it may not behave the way the JWT programs expect it to either, since they expect to find a new trans. I hope it does, but I won't know until I install the ECU/TCU. I'll be interested to hear what you find after you test with the fluid level adjustment and the filter/cooler changes (see if the rev limiter hits before the transmission shifts). It may just be that simple.
I agree with you about the manual shifting... the only reason I do it now is out of necessity to get the trans into 1st with the oem TCU. Once I have 1st gear start, I may only want to manually put it in gear on rare occasion-- but then I would like it to work.
I have no way to really tell how well "my" transmission guy did on my rebuild. I want to believe that it is sufficient, but since they didn't replace every gear/hardware component and blueprint the transmission back to oem spec... it may not behave the way the JWT programs expect it to either, since they expect to find a new trans. I hope it does, but I won't know until I install the ECU/TCU. I'll be interested to hear what you find after you test with the fluid level adjustment and the filter/cooler changes (see if the rev limiter hits before the transmission shifts). It may just be that simple.
I agree with you about the manual shifting... the only reason I do it now is out of necessity to get the trans into 1st with the oem TCU. Once I have 1st gear start, I may only want to manually put it in gear on rare occasion-- but then I would like it to work.
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Q45tech
- Moderator
- Posts: 14296
- Joined: Tue Apr 30, 2002 3:19 am
- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
The problem with independent rebuilers is most don't have transmission dynos [$150,000] to check their work, whereas the Jatco Nissan rebuild facility does have many more than 6 stations for Quality Control over employees and processes.
Jatco doesn't use Kevlar clutches and the like just makes sure they function in a narrow range as new.........many can rebuild better using better materials but do they always and how can they afford the time plus, how do they check their work.
Another thing to try is REDLINE High Temp ATF it is thicker [more viscous] than Dexron 111 ATF for use above 60F ambient [Spring Summer anf Fall use ONLY].http://www.redlineoil.com/prod...ID=19h ... /pdf/3.pdf
The shift pressure is set by looking at the ATF temperature, so using something thicker than expected raises the pressure.
It also makes the TC more efficient but creates more windage friction in gears and pump............all in all it seems to help more than it hurts in Hot weather!
Jatco doesn't use Kevlar clutches and the like just makes sure they function in a narrow range as new.........many can rebuild better using better materials but do they always and how can they afford the time plus, how do they check their work.
Another thing to try is REDLINE High Temp ATF it is thicker [more viscous] than Dexron 111 ATF for use above 60F ambient [Spring Summer anf Fall use ONLY].http://www.redlineoil.com/prod...ID=19h ... /pdf/3.pdf
The shift pressure is set by looking at the ATF temperature, so using something thicker than expected raises the pressure.
It also makes the TC more efficient but creates more windage friction in gears and pump............all in all it seems to help more than it hurts in Hot weather!
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Q45tech
- Moderator
- Posts: 14296
- Joined: Tue Apr 30, 2002 3:19 am
- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
The are 4 versions of Redline ATF that are Dexron 111 compatible.
The High Temp and Racing versions are the trick in SUMMER.Then you experiment with Lubeguard Black [in tiny amounts*] to compensate for increase viscosity.* 3 ounces at a time is about 1%What's $100 per year for ATF in a $4,000 transmission?
The High Temp and Racing versions are the trick in SUMMER.Then you experiment with Lubeguard Black [in tiny amounts*] to compensate for increase viscosity.* 3 ounces at a time is about 1%What's $100 per year for ATF in a $4,000 transmission?
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texasoil
- Posts: 875
- Joined: Mon Sep 02, 2002 3:18 pm
- Car: '92 Infiniti Q45A
'94 Infiniti Q45A
'94 Mercedes-Benz SL600
lubeguard red & black
Red is synthetic sperm oil (can't kill whales anymore) and is used to smooth out the final engagement shock (lock-up.) It is a friction modified that lowers the coefficient of static friction relative to the dynamic friction. Dynamic is when the clutch faces are slipping past each other--static is when they are stationary.
Black lubeguard increases static friction and dynamic friction coefficients, raising the locked-up torque handling capacity of the clutch unit (results in 'firmer' feeling shifts)
The Q45 TCU/ECU backs off on torque during the shift to give smooth shifts. For a given transmission condition/temp/oil condition, one can 'tune' the fluid characteristics somewhat. Factory settings are a compromise between smoothness, durability, and performance. Ideally you would get a continuous flow of driveshaft torque under all throttle and speed conditions, with no noticeable jerk or sag. Hard to achieve in this world.
You want to be careful with harsh shifts--they stress the metal parts and clutch faces (and driveline parts) more than intended. This is not to say they will fail (right away), but incremental wear/damage is unavoidable with hard shifts.
Black lubeguard increases static friction and dynamic friction coefficients, raising the locked-up torque handling capacity of the clutch unit (results in 'firmer' feeling shifts)
The Q45 TCU/ECU backs off on torque during the shift to give smooth shifts. For a given transmission condition/temp/oil condition, one can 'tune' the fluid characteristics somewhat. Factory settings are a compromise between smoothness, durability, and performance. Ideally you would get a continuous flow of driveshaft torque under all throttle and speed conditions, with no noticeable jerk or sag. Hard to achieve in this world.
You want to be careful with harsh shifts--they stress the metal parts and clutch faces (and driveline parts) more than intended. This is not to say they will fail (right away), but incremental wear/damage is unavoidable with hard shifts.