BRM 4.08 rearend swap now available!

Post by **jdmfreak** » Mon Feb 23, 2004 7:49 pm

Im askin you.

Post by **rsiwicki** » Mon Feb 23, 2004 7:49 pm

I get mine installed Friday afternoon....so I will report this weekend on how good it feels. I sure do think that I could have used it at the 1/4 track even if it does create an extra shift point in the 1/4 mile.

Post by **maxnix** » Mon Feb 23, 2004 7:49 pm

jdmfreak wrote:Im askin you.

Ask Fred. He's driven one for a year now.

Post by **AZ94Q** » Mon Feb 23, 2004 7:49 pm

I for one don't care about extra shifts...

Either do any of the car makers.

Look at the BMW 645..

It has nearly 50 less hp/torque then an XJR.

yet it runs an idential 1/4 mile

How? 6 gears, perfect optimization

Car makers are adding more gears, not less of them

In each case it speeds up 0-60 1/4 mile, etc etc..

More shifts, means nothing..

Post by **AZhitman** » Mon Feb 23, 2004 7:49 pm

Check out what SOME people are charging for this modification.

http://www.i-m-racing.com/stilq4590rea.html

:nono

Post by **AZhitman** » Mon Feb 23, 2004 7:49 pm

No need to. I bought a whole pile of the gearsets.

It's Nissan OEM parts, nothing that ANYONE couldn't pick up at their local dealer.

Post by **rsiwicki** » Mon Feb 23, 2004 7:49 pm

Wow!!!! $2,100 is insane. I get my gear in tomorrow. Not lets see what else can go wrong besides knocksensors.

Post by **AZhitman** » Mon Feb 23, 2004 7:49 pm

Rob - Don't forget to give me a call as SOON as it comes out of the shop!

Post by **zinkie13** » Mon Feb 23, 2004 7:49 pm

AZ...did you check to see if 4.08's would fit the 97?

Post by **AZhitman** » Mon Feb 23, 2004 7:49 pm

I didn't, I'm sorry.

Call one of our sposor dealers and ask if the rear diff is the same, or better yet, get us some good pics of the punkin on your car...

We'll figure it out buddy!

Post by **elwesso** » Mon Feb 23, 2004 7:49 pm

G50 Q has a 3.53 rear end, the Y33 has a 3.69... So the 4.08 would hardly be worth it, IMO.. Plus its most likely a different model diff...

Post by **HeavyDuty** » Mon Feb 23, 2004 7:49 pm

elwesso wrote:G50 Q has a 3.53 rear end, the Y33 has a 3.69... So the 4.08 would hardly be worth it,

I kinda like the idea of less than a 4.0 compared to a 3.5,3.7, or so also, Wes.

But these are heavy cars, and the increased torque will get these pigs out of the hole quicker, which is where everyone seems to have complaints with respect to acceleration.

Post by **jdmfreak** » Mon Feb 23, 2004 7:49 pm

Why not?

Post by **rsiwicki** » Mon Feb 23, 2004 7:49 pm

well I know have to wait till Tuesday to get my new 4.08. The mechanic that could do it left early for it being good Friday. So now on Tuesday is when I should have it done. Man...I can't believe my luck on trying to get my car all done. If this keeps up...then I am just going to send everything up there to T3 to be done....transmission, 4.08, driveshaft, brakes, knocksensors, etc. At least I won't be waisting my time driving to places where the mechanic went home early. I can understand that it is Good Friday....but we had spoke on Tuesday for this Friday to do the work....Ughh!!!

Post by **Q45tech** » Mon Feb 23, 2004 7:49 pm

T3 techs stayed [always stay till 5:59:59PM] even on New Years Eve.But we did have a [light] beer at 5:30 PM in honor of something.

Post by **HeavyDuty** » Mon Feb 23, 2004 7:49 pm

Greg, I'm still down for it, but I need to take care of raditator, fan, ps line stuff I'm currently dealing with first. Sure would be nice to have time to work on my own car.

Although, since it's down, I could go ahead & ship mine, but it's de-molished, I'm sure. There'd have to be an additional charge for one that's not exactly operational.

Also, what of the yoke compatibility?

Also, I'm unclear of the deal with the speedo gear & tack welding someone described. Is there no way to avoid that?

I don't suppose you'd sell me a gear set.

Post by **AZhitman** » Mon Feb 23, 2004 7:49 pm

You want a gear set? No can do - Shims and spacer are custom-ground by our tech....

Never did figure out why my yoke was different (albeit by only .013") from the donor car rear diff...

I need to research the speediogear issue as well. Rob, ca n you explain this a ittle more in depth?

Post by **rsiwicki** » Mon Feb 23, 2004 7:49 pm

Speedo gear??? I will tell you all on Tuesday after I install my rearend. It is suppose to go something like what I described above and actually inserts into the transmission.....not the differential itself. With any luck....I will post the exact procedure on Tuesday.

Post by **HeavyDuty** » Mon Feb 23, 2004 7:49 pm

Cool, thanks Greg, lemme know what you want for the set.

There should be a speedo sensor on the trans with either a cable attached or a electronic signal that's sent to the ECU or speedometer.

I read somewhere that the entire sensor has to be replaced and didn't fit just right into the trans, and it had to be welded (?!).

We should be able to get a gear that has the correct number of teeth that fits on our stock sensor to attach correctly into the trans.

The one on the nose of the diff should be for TCS.

Post by **Q45tech** » Mon Feb 23, 2004 7:49 pm

Gotta get your facts straight before you hit ENTER.

"The one on the nose of the diff should be for TCS."No!, ABS sensor.

TCS and Active cars have two, one one each output and none on input of diff.transmission [vehicle] speed sensor:"had to be welded (?!)." Say what it bolts in and changes quickly and easily

Post by **HeavyDuty** » Mon Feb 23, 2004 7:49 pm

Q45tech wrote:Gotta get your facts straight before you hit ENTER.

"The one on the nose of the diff should be for TCS."No!, ABS sensor.

I actually typed TCS or ABS, but then erased ABS. My mistake. It seemed strange to have an abs sensor in the pumpkin, a lot of cars have them on the axles, so as to determine which wheel exactly is locking up, or not.

Q45tech wrote:TCS and Active cars have two, one one each output and none on input of diff.

Gotcha, like above.

Q45tech wrote:transmission [vehicle] speed sensor:"had to be welded (?!)." Say what it bolts in and changes quickly and easily

It took me a couple of reads to understand your sentence. I now see what you meant to type was:

"Say what? The speedo gear bolts into the transmission and the correct gear changes quickly and easily!!!!!!!"

The following is the post where I read *something* about welding.

rsiwicki wrote:Speedo Gear Part # and procedure to get your speedo to work correctly.

Your local Nissan dealer can get you the speedo gear, but order inadvance as all the dealers here in Miami don't have it in stock.

The Nissan part # is 32743-35F20 and cost is about $17.95.

The speedo does not fit exactly and you have to do the following:

1. Rotate the new speedo in as it is wider than the OEM speedo2. It will look like that the gears will not fit, but they will after twisting in the speedo into the transmission to match the gears3. You will need relocate "tab" that holds the speedo gear in place with new spot weld to make it stay

Also it was suggested that we use a "LS Fluid with weight 85-140". He also said that the synthetic will free up the friction a little more. Is this the weight that you all use currently?

I now see he meant the tab that prevents the sensor from rotating, not welding the sensor itself.

Now I understand, so......thanks.....I think, and...uh....nevermind.

Post by **AZhitman** » Mon Feb 23, 2004 7:49 pm

I used Mobil 1 90w. Should I have used the 85/140? Experts please?

Post by **rsiwicki** » Mon Feb 23, 2004 7:49 pm

sorry for the confusion...but yes it is the tab that needs a quick little spot weld to hold the new speedo gear in place.

Kevin suggested we use the 85-140 weight when I asked him. The only synthetic that I could find in that weight was Valvoline.

Post by **qship96** » Mon Feb 23, 2004 7:49 pm

Redline makes a fantastic synthetic diff. fluid in both 75w-90 and 80w-140- both contain ingredients that are specifically made for limited slip rears. about 8 bucks per quart,and now being sold at advance auto parts all over the country!

Post by **Q45tech** » Mon Feb 23, 2004 7:49 pm

But a viscous limited slip module is A SEALED ASSEMBLY, therefore you don't want a limited slip additive.

The VLSD is very temperature sensitive so you are torn between a watery lube which will wear the gears and a thicker lube which will raise the heat from friction..........depends on how often you want to replace the diff and for what failure.

I was able to get good service for 200,000 miles [changing oem viscosity every 30k] and replaced at 235k due to lack of VLSD action.

Many of the high mileage Q running around have weak VSLD!

Floor it in rain in first gear - do both wheels spin equally [good].

Post by **elwesso** » Mon Feb 23, 2004 7:49 pm

Mobil 1 GL-5 should have been used, 80w90...

Post by **qship96** » Mon Feb 23, 2004 7:49 pm

Q45tech wrote:But a viscous limited slip module is A SEALED ASSEMBLY, therefore you don't want a limited slip additive.

The VLSD is very temperature sensitive so you are torn between a watery lube which will wear the gears and a thicker lube which will raise the heat from friction..........depends on how often you want to replace the diff and for what failure.

after checking the Redline website,they state that the gear oil is recommended for conventional and limited slip diff,so it should work fine. they list the 80w-140 oil as .5% less efficient over 75w-90,so either will work in the q rear.I have used the 75w-90 for over 100,000 miles{changed annually} and now have 133,000 miles on the diff. and it is quiet as new,and passes the spin test!much better basestock than most other oils.

Post by **Q45tech** » Mon Feb 23, 2004 7:49 pm

Don't think that 0.5% is insignificant, as that would be over 1 extra HP lost to heating the diff fluid and case in WOT high rpm use.And 1 HP= 12,000 BTU...........even at 80 mph cruise that could translate to a 20F warmer diff...........see the cooling fins on early diffs!

Post by **AZ94Q** » Mon Feb 23, 2004 7:49 pm

How about the Diff cooler from the 300zx..

AGM has it installed on his Q.. It's an OEM part..

I think he complained about the noise it makes, but that was about it

Post by **AZhitman** » Mon Feb 23, 2004 7:49 pm

I've heard both positives and negatives on the diff cooler... Well, not really negatives, but people saying it's unnecessary, so i don't know - I can't see that it'd hurt anything, and at the very least would add some extra capacity.

BTW, my replacement diff (with the 4.08's) has a finned cover and a larger sump, whereas my original had a smooth cover and no sump. The replacement appears to take an additional 1/2 quart of fluid (woo hoo!).

I need an IR thermometer so i can see what the temp gets to...

Also, I know my VLSD is working properly - i have about 20 feet of identical thick black striping in front of my house as evidence....

BRM 4.08 rearend swap now available!

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