Nissan 240SX Forums banner
Cancel
Create thread New Garage Forums

Shimming an R200 or J30 vlsd

Jump to Latest
24K views 27 replies 18 participants last post by  nightferret  
#1 ·
By: Hunter Rodziczak

I could not find a comprehensive guide to doing this, So I thought I would make one for the good of the S chassis community.

Benefits: Get clutch type lsd action for a 1/4 of the price.

Well post j30 VLSD installation I found myself quite unsatisfied with the performance. As with Many VLSd's after becoming heated up they simply refuse to work properly and your VLSD becomes a one tire fire and thats no good. So after looking for upgrades I stumbled across a few options. Since I have a J30 vlsd with 5 bolt output shafts I would have to switch back to the standard 240sx R200 differential housing in order to run a clutch type lsd. I sold my old diff and a clutch type lsd wasn't in my budget. Somehow I stumbled across Shimming. Shimming involves adding an extra shim(s) to the original preload shim and causes the vlsd to lock similarly to a clutch type lsd. This preload shim costs $10 from you local Nissan dealer so this is definitely worth the money.


-Add one shim and vlsd will act similarly to a 1.5 way lsd

-Add two shims it will act like a 2 way/welded diff.

Here is a picture of the Shim with part no: ( this fits both j30 and R200 diffs)
Image

Here's your standard diff, Start By removing the diff from the car and unbolting the 8 bolts holding the diff cover on.
Image

Once that is completed, separate the cover like so and before you put the new sealant on remember to scrap off all old sealant and I recommend using brakecleen to clean surfaces before applying sealant back on.
Image

This is what you'll see:
Image

Next before anything else knock out the output shafts. This takes quite a bit of effort but don't be scared they will eventually come out. I recommend hitting them from behind with a hammer:
Image

Next you can take off the cap bolts like so:
Image

IMPORTANT: Remember which side the shafts and caps cam from as to not mix them up
Image

And this is what you're left with:
Image

Next, it's time to pry out the differential. Unless you have superhuman strength you have to get it out using a bar that give leverage:
Image

And end result:
Image

Unless you have a very good impact gun the next part is almost impossible. Take these bolts out to separate the ring gear from the diff.
Image

Next take off these two Phillips head screws.
Image

Pry apart:
Image

The Almighty shim:
Image

Now take this and put it over the existing shim:
Image

And now put the diff back together the same way you took it apart.


Impressions: Awesome locking compared to the stock vlsd can't complain.
 
C
#10 ·
Ideally you would be doing this on a well used vlsd. Since the viscous unit is sealed and not serviceable, premature wear should not be an issue. Damage, no it's just pre-loading the diff. Damage my occur from improper install but that's with anything. All in all, a good way to bring back a Used VSLD for cheap If you DIY that is.
 
K
#24 ·
Your overlooking the shim for the right side output shaft.

By only shimming the left output shaft, you are leaving alot to be desired in terms of performance. There are 35 different shim thicknesses available from Nissan. My left side shim measured 1.05mm while the right side shim measured .99mm This is why VLSD s13's do solid tight donuts to the left, but when you try and spin them to the right they will let go of the right wheel. It is engineered this way because these cars are already a handful for the general public with an open diff in the rain. So if your going to take your diff out and do this, you might as well get 2 shims and shim both sides. Dont take a shim and place it over an existing shim. Take a micrometer, measure thickness of left side shim and order 2 of those, or the next size up. I ordered two 1.4mm and two 1.7mm shims. I will try the 1.4mm first and report back.

if anybody is interested I can get pictures of the right side shim. It is SUPER easy to access, nothing needs prying or taking apart. Flip the differential 180 from how it is pictured with the cover removed (one held with 2 philips screws) and everything slides right out. done.
 
#27 ·
i got a 180sx vlsd in my 240 and heard of shimming. i searched it and found pros and cons. but honestly its something i wouldnt do. adding something where there shouldnt be usually isnt that great of an idea in the long run. imo. but if it works thats cool. id just save the money and get a 2way lsd or something :/
 
Nissan 240SX Forums
posts
1.6M
members
94K
Since
2002
A forum community dedicated to Nissan 240SX owners and enthusiasts. Come join the discussion about performance, builds, engine swaps, turbos, modifications, classifieds, troubleshooting, maintenance, and more!
Full Forum Listing
Explore Our Forums
S13 240SX (89-94) New Member Introductions SR20DE & DET General Tech