My car has been running great up until this morning when my nephew drove it to go pick up a check. What is happening is when it shifts, it goes from 1st to 3rd and will not go into 4th. When it shifts from 1st it is at around 3500 rpm before it goes to 3rd. It seems as if the solenoids for 2nd and 4th are not responding. It started this suddenly after leaving a light. I had the transmission fluid changed about 4000 miles ago with autozone brand Dextron III and I added LubeGuard Black for the friction modifiers since I didn't use NissanMatic-D and I installed an inline magnetic transmission filter. I'm not getting a trans malfunction on the display either. Any ideas? It shifted firm before and when it shifts to 3rd it still does.

Did you run the self test yet? I would start there and of course checking the fluid. How much lubeguard black did you add?

Heath

How many total miles are on this rebuilt transmission?

Q451990....No I haven't run the diag yet. I will when I get home. I have to get the book out to see how to do the diag as its been a while since I did it before. I put the complete bottle in.

Qship96.... I was told that it was a rebuilt tranny when I pulled it from a parts car that I got but I never got any verification of that as the previous owner never did follow up on it to find out. The car actually was his fiancee's that she had bought from her parents. I have put 4000 miles or there-about since I installed it in the car. I know it wasn't a replacement from the dealer because it didn't have a drain plug in the pan.

If i am understanding you correctly......we are talking about a transmission that if rebuilt, was not a genuine factory rebuild {due to the lack of having a drain plug in pan}and that we have no idea how many total miles of use it currently has on it. Makes it hard to figure out exacty what you are dealing with,as it could be just worn out due to high miles, or could be a low mile unit with other issues????

I would drop pan, inspect filter/magnet for excess debris and refill without adding any lubegard and see if it changes operating performance at all and make decisions based on what you find in the pan.

Ok... I just finished performing the self diag and the TCU gives "OK" after the test but I get a transmission malfunction as I am test driving it. I started off driving the car in Drive and noticed that the car would not shift until it got to almost 3600 rpm and when it did shift, it went straight to 3rd and stayed there. When I moved the selector back to 2nd, it would drop down to 1st. The car just did this out of nowhere. I figured that if the clutches were worn that I would start to notice slippage but the car shifted firm in all gears. It shifted good before I changed the fluid and added the lubeguard. I only added the Lubeguard because I didn't have any Matic-D to put in it and instead used the Autozone brand.

Is there a solenoid that ties 2nd and 4th together?

I think you have confused the discussion about the Nissan D fluids and Nissan J ATF. As far as I can recall, Nissan D is just Dexron... so the discussion about friction modifiers isn't that big of a deal for the older transmission. Q45Tech tends to talk about adding a few ounces at a time... not a whole bottle of the Lubegaurd Black. I think I would start draining and refilling with new ATF to get some of the Lubegaurd out.

If you are getting a "transmission malfunction" message while driving, you should be able to pull the code by running the test again. The solenoids should be fine if it passes the self test.

Oh, and the lack of a drain plug isn't always an indicator of the transmission not being an OEM rebuild. I have gotten them with and without... I think they just put whatever pan they have clean and available on them.

Heath

I drove the car to the store this morning and noticed that when it is cold, it will shift to 3rd from 1st at 3,000rpm if your easing on the throttle. After it was warmed up, it didn't shift to 3rd until it reached 4,000 rpm.

Edit...

As to your last post, I did the test again after getting the malfunction and the test still finished saying "OK".


Modified by mattd1979 at 12:56 PM 10/4/2008

OK.... I got up under the car and checked all connections which are good. I also checked the TPS as per the troubleshooting section of the FSM which is also good. I did a final self diag and it still checks out good. The car shifts like a 2-speed powerglide. I am going to post this over in the Q45 forum also to see if anybody over there may have any ideas.

When self check shows ok and sensors test good, you swap in your spare TCU. If it still is bad you swap in your test transmission.

The diagnostic system only checks external sensors and the solenoids in valve body.

There are test ports to measure internal pressures but the above usually solves the problem.

My 1990 Q is on tranny number 3 and I have a spare standing by since #3 [factory reman] has 95k already.

Always important to SAVE 3 cents per mile driven for tranny replacement.

I jacked up the rear of the car and placed it on stands so that I could run it thru the gears. I noticed that as I would shift up manually, it would not ingage in to 2nd unless I down shifted from 3rd. When I did I noticed the speed drop from 40mph at 2,000rpm to 20mph and when I would push the pedal down a little more I noticed the speed slowly climb but not as quick as it should. I then down shifted to 1st which took it down to 10mph at 2,000rpm. When I gave it gas after putting it back in 3rd, it wouldn't shift back up to second. Instead it would just jump to 3rd. I also noticed that the lockup converter would not lock into 3rd once it was there. I wonder if maybe a solenoid is not fully functioning or stuck and that is why 2nd doesn't fully engage. It's also a mistery as to why the lock up doesn't work nor does 4th gear.

I swapped in my 2nd gear start and now the car starts in second but it still will not go into 4th nor will the torque converter lockup.

I still think I would start swapping fluid... I'm not sure that a whole bottle of Lubegard black was a good idea.

Heath

Q451990 wrote:I still think I would start swapping fluid... I'm not sure that a whole bottle of Lubegard black was a good idea.

Heath

A hearty second here.

The original poster (and quite a few others) could save a lot of time, money and self inflicted injury by reading the previous posts and judiciously weighing the advice therein.

I put the fluid in just before I started driving the car and it has run fine with two trips to Jacksonville and back which is 180 miles one way and other long trips that I have made between Tampa and Zephyrhills without a skip. I will drop the pan tomorrow to see if I can find anything in there that may be out of place.

I still have the bottle of lubeguard Black and according to what it says for normal applications, use 1oz per qrt. of Dextron III to the total transmission capacity (including torque converter) with motor idling in park.According to my FSM, the trans oil capacity is 9-1/8 qts. The bottle has 10 ounces in it. I put 9 in the transmission. I read a post by Q45tech that stated that if I didn't use NissanMatic-D to use the Lubeguard Black because regular dextron III doesn't have the friction modifiers that NissanMatic-D has, otherwise use the lubeguard red. That is why I got black because I didn't have NissanMatic-D.

Lubeguard [either color] just changes the scientific feel of a shift.

Mechanical failures or just a bad worn, dirty, gummed up valve body.

mattd1979 wrote:I read a post by Q45tech that stated that if I didn't use NissanMatic-D to use the Lubeguard Black because regular dextron III doesn't have the friction modifiers that NissanMatic-D has, otherwise use the lubeguard red.

I believe this to be the definintive post by TexasOil about Red vs. Black.

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 tranny 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.

Regarding Lubeguard. (No comment on Nissan D fluid since I am ignorant of the specific characteristics) I AM knowledgeable on DEXRON (all previous and present versions) and the 'type F' fluids.

Q45's through version III for certain were designed for the friction characteristics of DEXRON. This fluid had friction modifiers that shallow the slope of the torque vs slip curve as the clutches approach 'lock-up'. AND these fluids are suitable for those cars that ALLOW continuous slip of the 'lock-up' torque convertor to smooth things out.

Some transmissons are designed for different fluids, ones that have either no drop in torque transfer as slip goes to zero, or even fluids that have HIGHER torque transmission ability as slip drops to zero. This characteristic is called HIGH STATIC FRICTION. Dexron fluids have HIGH DYNAMIC FRICTION.

If youput a 'high static' fluid in a transmission designed for 'high dynamic' fluid, you will significantly increase clutch lock-up shock--even to the point of shearing the metal driving lugs on the clutch plates. You may even feel a 'firmer shift', but that is easily confused and misnamed. You can also get a 'firmer [faster] shift with higher viscosity fluid or increased oil pressure in the transmission operating circuit. 'Firmer shift' and 'clutch lock-up shock' are different processes and not necessarily coincident. You can have 'soft shifts' caused by worn clutches, leaking clutch pack seals, low oil pressure, and STILL have 'lock-up shock.' You can have fast, firm shifts and still have smooth , no jerk clutch lock-up.

I recomend AGAINST adding Lubegard BLACK to Q45 transmissions in an attempt to get 'firmer shifts'. All you are doing is increasing the momentary torque loading( lock-up shock) on the metal parts in the tranny and can brak some real expensive parts. This transmission IS NOT designed for harsh shifts and WILL break.

IF your Q45 tranny has slow, lazy shifts at moderate and more throttle openings, slips on shifting (engine speeds up), then either your throttle position switch is misadjusted, the transmission is worn and leaking internally, the oil filter is plugged, the fluid burned (worn-out), the clutch linings coated with varnish (from infrequent oil changes) or the valve body is malfunctioning for some reason.

Change the fluid. Add one pint of Berrymans Transmission cleaner and seal conditioner--run it easy for a week, re-drain and refill with DEXRON III --not synthetic--most DEXRON III fluids already have as much as 50% 'synthetic' base oil in them to meet the very low temperature viscosity requirements. What you are trying to do is clean off the clutches, clean out the valve body, and renew the friction modifier additive package. IF the shifts are not velvety smooth on lock-up, add one pint of LUBEGUARD RED. Do not confuse 'smooth lock-up' with 'firm shifts'. DO NOT ADD LUBEGUARD BLACK trying to get 'firm shifts'. To get 'firmer shifts' you will need to increase the transmission 'line pressure'. There are after-market spring/parts kits to do this. Use at your own risk. You DO NOT want to create harsh clutch lock-up under any condition--the metal parts will not survive.

I sucked the fluid out thru the trans dipstick tube and dropped the pan. I noticed that as I was removing the bolts that one of them appeared to be a wood screw but with a hex head of the same size as the rest. After I dropped the pan, I noticed small slivers of metal attached to the magnet. I also noticed that the pan gasket was a cork gasket so I guess the pan has been off before. Anyway, I want to check the solenoids resistence as per the book but it doesn't give a very detailed pic of the wiring.

A solenoid is a coil with only 2 wires......detailed pic of wiring? Try FSM pages AT-39-AT-41. All solenoids are available on M289 connector with the other end grounded.

I tested all of the solenoids from the connector on the outside of the transmission per the FSM and all turned out to ohm good. As far as them functioning is another story. I test drove it and I noticed that is still starts off in 1st gear even with the 2nd gear start installed. I also noticed that when I am at 45 with the car in drive and let off the throttle, the rpms will drop to 1,000 rpms I believe and when I ease back on the gas the rpms will climb back up to 2500 and then grab. If I put it in 3rd as I am at 45mph, as soon as I let off the throttle, the car will slow down as fast as the rpms drop. The same goes for 2nd. If I am at 20mph with it in 2nd and I let off the throttle, the engine will slow down faster then the car does and when I give it throttle, it will rev back up before it engages and brings the speed back up to 45. If I leave it in 1st and maintain 20mph, as soon as I let off of the throttle, the engine and speed both seem to slow down at the same pace. I also noticed that 3rd gear lock up was working because I noticed the tach drop a notch soon after it engaged 3rd and I could ease on the throttle and feel it drop out almost like downshifting. On the way back though, it didn't seem to be working. It almost seems like an electrical problem at times unless one or two of the solenoids are stuck. I am going to have it flushed this coming Sunday at my buddy's shop. They use BG products for fuel injection cleaning and transmission flushes.

Pay attention to the color difference between the new fluid going in to push the old fluid and detritus out.

Consider performing a chemical flush with BG Quick Clean for automatic transmissions.

When I sucked the fluid out of the transmission into a clean bucket, I noticed that the fluid had a creamy burgundy graphite color to it. I have an inline fiter that has a paper element inside along with a magnet so I'm surprised that it didn't catch any of the graphite looking material that was in the fluid.

Have you replaced that inline filter and filter screen? With that much stuff floating in the fluid, I would be concerned about fluid starvation and reduced line pressure from clogging.

Heath

I don't know why no one has mentioned it yet, but it sounds like the tranny is going in the fail-safe limp mode. Is that right?

Haitian_King wrote:I don't know why no one has mentioned it yet, but it sounds like the tranny is going in the fail-safe limp mode. Is that right?

That's what I was going to say. I'm sure it has very little to do with Lubegard regardless of color.

I replaced the filter with no change. I can understand if one gear started to go out or I lost all forward gears but not every other gear. I did another diag check with the display and still I am getting an ok message. I have no 2nd nor 4th. I disconnected the connector for the transmission that is mounted on the passenger side inner finderwell under the battery to see how it would respond. It seemed to firm up the shifts more but thats about it.

If it really was is in a fail-safe mode then it should be operating a near max line pressure and you should be experiencing hard than normal shifts without that connector disconnected. It would also be engaging into gear harshly. But, it would also seem like the TCM would output some kind of trouble code.

You really should have a line pressure test done on this thing. That's really the best way to know how the internal mechanical parts are doing without taking the whole thing apart. Something may be leaking/by-passing internally not allowing a clutch pack to engage. Or one of those solenoids you checked may not be working. You can always try energizing each solenoid to make sure they make a loud click when engaged.

EDIT: Just looked at the FSM...well for a 94 Q45 at least. The band servo should apply for both 2nd and 4th gears in all ranges; when the gear selector is in 'D' or '3' position. To get 2nd gear, the RE4R03A applies the forward clutch pack and the band servo and the forward one-way clutch is locked. The forward clutch is working because it is used in 1st, 2nd and 3rd gears, as is the one-way clutch. But the shift into 2nd gear from 1st is accomplished simply by applying the band.

I'm guessing if you shift the gear selector into '2' manually you will still have 2nd gear as it does not use the band in this position to get 2nd gear. Manual 2nd gear applies the forward clutch, overrunning clutch, and locks the forward one-way clutch but no band is applied.

Also, band servos are usually located in the area of but separated from the valve body. There is a seal around the servo piston that could leak pressure and cause the servo to not fully apply.

Or I could be completely wrong!
Modified by Unnatural1 at 11:54 PM 10/11/2008

I am getting a transmission pressure gauge this coming thursday and will check the pressure on the transmission at the ports on the rear. What are the normal pressure readings? I noticed that there are 3 ports to choose from. I figure one must be for reverse. Should I be driving the car when I test it? Could I put the rear on stands and drive it inplace to get the pressure readings or do I have to have a load on it?

I also should note that when I had the dropping resistor (I believe that is what it is called) unplugged, I noticed also that when I put the shift selector in 3rd and whould let off the throttle, that the transmission sounded as if it was trying to downshift into second. It would engage and disengage 3rd every 2 seconds until it got slow enough to ingage 1st. If I put it in D however, it wouldn't do this.

Do you by any chance know which line is the output line from the transmission? I believe I have the filter in the right direction, just want to ask to be sure. I am having trouble locating my FSM which happens to be in 4 different pieces. It is well used.
Modified by mattd1979 at 11:45 AM 10/12/2008

There are 2 test ports on the bottom of the transmission at the back of the pan; between the pan and the crossmember. The port on the driver's side is for Reverse and the other (on the passenger's side) is for all forward gears. You do not need to be driving the car to perform the test. Transmission line test specs are specified at idle and stall speed. So this should all be done in the garage with all four tires on the ground (once the gauge is connected).

Remove the passenger's side (D, 3, 2, and 1) plug and attach the pressure gauge. I usually tape the gauge to the windshield OUTSIDE of the car. You will start the engine and allow it and the transmission to fully warm up to operating temperature. Once at operating temp, note the line pressure at idle for all forward gears. Then, starting with D, fully depress the brake pedal and slowly press the gas pedal at the same time to slowly bring the engine to stall speed (or as close to max stall RPM without spinning the tires) and note the pressures for the forward gears. When doing this test you need to allow the transmission to cool down between each gear. I would leave the engine running at idle for AT LEAST a minute or longer before going to 3, 2, and 1. All the pressure readings should be close to the same in each gear.

Now, again let the transmission cool at idle then shut off the engine. Remove the pressure gauge from the Forward test port and install the plug. Remove the Reverse test port plug and install the gauge again. Follow the same test, idle and stall test, for reverse. The highest line pressures should be achieved in reverse.

Line Pressure Specs:D, 3, 2, and 1: 65-71 psi @ idle148-159 psi @ stall

Reverse:91-97 psi @ idle206-219 psi @ stall

There you go...let us know what you get.