vlsd rebuild

[jeff420]

you wont need a new driveshaft unless you do a 5 speed swap

[spooled240]

cant wait to install my new vlsd, its pretty. painted it orange. couldnt find hot pink paint, lol.

a hot pink differential?!! That would look like a pair of balls under the car

Oh and you will be fine having the auto, they made automatic 240's with vlsd's. I'm thinking of the ABS sensors on some vlsd's that make the differential longer by about .75 inch.

[Beanstalk]

OP, buy it.

A vlsd has a sealed viscous coupling which has 2 or 3 slotted discs submerged in a thick silicone based fluid, when the disc start to slip under hard acceleration then the fluid gets hot and hydraulically binds the discs together to make both output shafts spin at equal rates.

What spank said is textbook and is really the only to try to visualize how the vlsd works

[Beanstalk]

N

hell yes the vlsd will be a night/day difference compared to the open diff. No more one wheel burnouts on hard launches or hard cornering and a lot more added traction in rain/snow/mud.

I heard that the vlsd unit is not rebuildable, or it is not designed to be rebuilt as the thick silicone-based fluid in the viscous unit is totally sealed from the gear oil you put into it. So changing the gear oil will help your vlsd last longer as far as lubrication and heat(same reason you change the oil in your car, replacing worn-out oil) but it won't rejuvenate the viscous unit persay.

There is, however a way to have your worn out vlsd to lock much better. You can shim your vlsd and depending on how thick your shims are, you can have your lsd lock like a 1.5way or a 2 way(welded) differential. A shim from nissan is around 10 bucks but you will have to open your differential up a little bit.

there is a good write-up on zilvia:http://zilvia.net/f/s-chassis/....html

or just search "shim vlsd" on google for some other results

NOOOOOOOOOOO dude you cant tell a newb to pull his diff apart and throw some shims at it ... the shims are there for a reason ( to set backlash on your ring and pinion gear ) if you have to much left or right it will cause your center-section to be off and whine or chatter and it would kill his pinion gear and bearing trust me not a good idea

[Beanstalk]

I mean i worked at dana making rear-ends and we put 25000lbs. of force to stretch the carriers to get the proper shims in there but that was fords allum. front centers but we do the same with the titan and frontier

........ dude i bet your diff is fine buy it put it in and happy sliding

[spooled240]

to my understanding, inserting one large shim from the nissan dealer will make a vlsd lock like a 1.5 way clutch-type lsd which is not dangerous at all. The only thing different from a 1 way and a 1.5 way is the decel characteristics, where the 1.5 way will lock a little more upon decelerating which can be a little more dangerous.

What you are talking about sounds like a welded differential or a 2 way lsd. Stacking shims will make a vlsd lock like a welded but starting off with one large shim is not crazy.

[turoki]

damn im really confused i got the vlsd now but i dont know if i should throw it in or shim it first i mean im a mechanic but im not a rear end specialist i dont want to mess anything up but im not afraid to open stuff up and mod. any one have any suggestions?

[spooled240]

take it to a h0m0, they are rear-end specialists haha j/k

but for real, check out that link in my first post. It has pictures of a rear end and how to open it up(no h0m0)

[liquid_cool]

I used to work at dana axle and guys argued about this topic all the time point is yes you can rebuild them but there are tricks that you can do to bring life back into your vlsd like friction inhibitor that big trucks use the oil in the diff should be changed and i hear you can also hose the IU down in brake parts cleaner and let it dry out then re-oil and acts as good as new

have any dana 60's laying around from when ya worked there?..lol..thought id ask

for those not in the know..dana 60's are b0mber proof drag shizts..next to impossible to destroy..anyways.

[spooled240]

my dad's got one in his 67 barracuda. It locks like a mofo and makes some weird noises around turns lol

[turoki]

take it to a h0m0, they are rear-end specialists haha j/k

but for real, check out that link in my first post. It has pictures of a rear end and how to open it up(no h0m0)

i saw the link i want to go with a 1.5 shim but it just seems a lot of people say that it can cause premature damage or mess up the rear end all altogether.

[spooled240]

i saw the link i want to go with a 1.5 shim but it just seems a lot of people say that it can cause premature damage or mess up the rear end all altogether.

with one shim to make it like a 1.5 way you should be fine. This is actually an old mod that has been used in racing and it's been working great for a lot of peoople.

[Beanstalk]

to the guy asking about the dana 60 what do you want ? full axle will run me about 500 with no rotors or calipers now i might have to mark it up a tad

[turoki]

i was reading that there is a shim thats 1.49 part# 38424-40F83 so i was thinking about removing mine which is probably a 0.80mm or a 1.01 that way i only have one in there. any suggestions on single or double shims?

[spooled240]

I heard that having double(stacked) shims can cause some warping and stuff but this is just from what I heard. If I were you I would remove the stock shim and throw the 1.49mm shim in there. Just one solid shim and you'll have a pretty damn good vlsd that won't be a full locker but also not a weak sauce lsd.

[turoki]

I heard that having double(stacked) shims can cause some warping and stuff but this is just from what I heard. If I were you I would remove the stock shim and throw the 1.49mm shim in there. Just one solid shim and you'll have a pretty damn good vlsd that won't be a full locker but also not a weak sauce lsd.

yeah thats what i heard too a bout two warping so you think the 1.49mm wouldent be to much for the spider gears?. did you shim yours up yourself ?

[spooled240]

nah I just did some research and looked at some write-ups. I never did it but it doesn't look hard at all. Are you pretty good at mechanic work?

[turoki]

nah I just did some research and looked at some write-ups. I never did it but it doesn't look hard at all. Are you pretty good at mechanic work?

yeah im pretty good but i just never got all into diffs thats all. i heard that you need to check clearances and stuff like that or it can get major premature damage thats why im concerned.

[spooled240]

Yeah it's recommended that you check your backlash but most likely the vlsd is fine.

[gregom]

Sorry to bring an old thread back to life but i'm really considering doing this to my 350Z. My concern is the spider gears overtime... has anyone opened their diff back up after using this mod for a few months or more after track day abuse? Unfortunately my Z is my daily driver so I don't want to do anything that could affect really reliability.

Now if the spider gears will indeed get worn over time, can they be replaced rather easily? Also why kind of issues can I expect trying to drive with worn spider gears?

Does anyone here have this mod done to their VLSD? How long have you been running it shimmed? Have you had any problems? Do you track your car and if so how often? Daily driven?

[gregom]

No one??? Who has had this mod on their diff for at least a few thousand miles or more? Any negative side effects or problems?

[gregom]

Com'on gotta be someone running this mod in their drift machine or something...