Diy:diff Shimming For R33 Gtst

[mark660]

can someone in perth tell me were they orded theres from i cant find any nissan spare parts web sites that have it?

[W0rp3D]

can someone in perth tell me were they orded theres from i cant find any nissan spare parts web sites that have it?

tried nissan?

Or maybe a diff place. ring and ask them where they get theres, teh intranets is not always the answer.

[psycodelik]

Order them from nissan, the part numbers on the first page are correct and their called thrust washers, not shims, i bought 2 1.5mm shims and it cost me 16$ total,

also AWESOME tech guide, greatly appreciate everyone for contributing

[33drifta]

ITS someones LUCKY DAY in melb if your thinking of doing this!!! im selling my car and need a stock (un-shimmed) diff. i did this mod to my diff (read back in this topic to see my thoughts). mine is nice and tight still and going strong as ever. give me your stock (working) diff, and you can have my already to go shimmed diff! pm me or call me 0400119068. cheers, Shane.

[na beast]

Shimmed mine to 2.8mm preload just died last night after only 3 weeks :S

Doesn't sound right to have only lasted 3 weeks so going to have to take it apart again and take a looksie.

Definitely going for more lock this time tho.

James

[spenda]

hell yeah, didnt even know about the diy section of sau until today. then finding this tutorial, nice nice...

thanks for the detailed info and plenty of pics

A++

[nisbne]

thanks for the info

[-Jimmy-]

I'll just let everyone know, I learnt a LOT while doing this.

I ended up using a 1.05mm shim, and 1.40mm shim (2.45mm all up) and I drove my car for the first time tonight and it is completely locked.

I certainly wasn't expecting it, as I was already running 1.95mm and I thought .5mm won't make a heap of a difference.

Also while reading the thread people using 2.6, 2.7 and 2.8 never seemed to end up with a locked diff. I'm quite stumped to be honest.

I either did it really right, or really wrong. I am using Castrol VMX90 oil.

The behaviour of the car is dramatically different, and even on slight bends you can feel the car wanting to push forward rather than easily coast around the corner.

I'll let everyone know how it feels when it has settled in.

-Jimmy.

[SLY-33]

I added 2 x 1.1mm shims to the existing 0.8 shim and was shocked to only see it single during it's first set of donuts

[-Jimmy-]

That doesn't make sense. That would equate to exactly 3mm of preload? I put 2.45mm in mine and it skips the inside wheel on full lock when parking.

I've driven mine for a few weeks now and it's definitely loosened up. It's probably the best I could ask for, still good for the street but very tight and predictable.

Edited February 22, 2010 by -Jimmy-

[NMD]

it will depend on how worn the diff is. more wear to the spider gears the larger the shims need to be. can also depend on the oil you use as well.

in my cefiro ive used around 3.2mm of shims as well as 140 weight oil....... the diff was worn out before the shims, would only spin one wheel, but now it doesnt have a choice, its both every time and chirps doinf u-turns.

which is fine because its my drift car

Edited March 23, 2010 by NMD

[Mr. Untouchable]

just fitted another diff into my 33 gtst. I purchased a second diff so I could work on one without pulling out my orginal, plus I have a spare housing so when I do finally get a 1.5 way I can slot it straight in.

anyways I pulled the new diff down, very clean and very good condition. It already had a 0.8mm shim plus a 1.4mm shim, so it had been done before. I added another 0.8mm shim to this. So all up it has 3mm of preload. just put some 80-140w nulon high performance oil in it and took it for a lash over some twisties. I'm really impressed with it, very predictable. It's pretty damn tight, kinda mini spool spec doing a 3 point turn but its not too bad.

for the money/effort I think its a excellent mod. Very impressed

[Leons14a]

Found my job for next weekend, the biggest let down with my car atm is the diff

[stuart7926]

great info good read didnt need to ask a question

[Rolls]

Has anyone considered changing the actual viscous fluid in the LSD centre? As changing the preload is really just a tightass hack that won't really work that well. It either locks or open wheels sort of thing, no middle ground where its like 50% locked. The only time you could achieve the nice medium is if your diff was still in good condition and not completely open wheeling.

I've heard of people putting thicker fluid in the viscous centre in 300zx's etc so surely it can be done here, is the centre serviceable, like can it be unbolted and pulled apart? If so it would just be a matter of finding out what fluid is currently in there and replacing it with something thicker.

Anyway let me know if anyone has done this before or knows if the oil can even be changed.

edit: Perhaps I am wrong but I am assuming that the diff centre is sealed and uses a different oil to the actual diff crown and pinion, if not could we just experiment with putting thicker oil in the diff itself? Would make the car slightly more sluggish, but might make a big difference.

Edited June 26, 2010 by Rolls

[W0rp3D]

Has anyone considered changing the actual viscous fluid in the LSD centre? As changing the preload is really just a tightass hack that won't really work that well. It either locks or open wheels sort of thing, no middle ground where its like 50% locked. The only time you could achieve the nice medium is if your diff was still in good condition and not completely open wheeling.

I've heard of people putting thicker fluid in the viscous centre in 300zx's etc so surely it can be done here, is the centre serviceable, like can it be unbolted and pulled apart? If so it would just be a matter of finding out what fluid is currently in there and replacing it with something thicker.

Anyway let me know if anyone has done this before or knows if the oil can even be changed.

edit: Perhaps I am wrong but I am assuming that the diff centre is sealed and uses a different oil to the actual diff crown and pinion, if not could we just experiment with putting thicker oil in the diff itself? Would make the car slightly more sluggish, but might make a big difference.

the answers to you questions are in this thread, read it.

[Rolls]

the answers to you questions are in this thread, read it.

I read every page, or at least I thought I did, no one mentioned opening up the actual centre and changing the viscous fluid.

[mark33gtst]

I read every page, or at least I thought I did, no one mentioned opening up the actual centre and changing the viscous fluid.

The center is not sealed.. Uses the same oil as the rest of the diff.. You can change the oil to a thicker oil but it doesn't last.

[Rolls]

The center is not sealed.. Uses the same oil as the rest of the diff.. You can change the oil to a thicker oil but it doesn't last.

What happens, only makes a slight difference? What if you almost double the thickness of the oil?

Probably wear the components faster and make the car ever so slightly slower, but be interesting to see the effects on the LSD.

[jester_oh]

ive just had mine out and i see what you mean about the clutch in there being sealed . i think your right the oil should have no noticeable impact .

just to add to the info available i found in my diff an

0.8 mm washer and a 1.5 mm washer for a total of 2.6mm . it drove very nicely , didnt single spin ever as far as i could tell . (feeler gauge is what i used to measure , there cheap)

i purchaced 2 1.1 mm washers with the plan to jam anything i could in there to lock it up tight for drift work . I could only fit one of them in there for a total of 3.4 mm as theres only so much you can fit in before the 2 screws that hold it together start to look too weak to pull the thing back together .

end result is a win for me , nicely locked up with no real movement . i think occasionally i can hear the spider gears moving half a tooth but it may be the tyres too . drift practice in 3 days woooo.

update .

been drifting for over a year now . no issues . fully locked . no noises ever just tyres doing there thing .