Front VLCD diff?

[fueledpassion109]

So i have done some searching around but am getting conflicting infomation about installing a front lsd.

 

I have a 97 pathfinder with factory rear lsd,

 

I also have a 300zx Z32 VLSD DIFFERENTIAL which I think is a R200... I want to install the differential to the front axel, from my understanding I should have a r200 front axel.

 

So can anyone clearify if this will work for me... I am also to the point of just dropping the front axel and find out for myself. IF it all fits, ill get some pictures and a write up!

[XPLORx4]

The R50 Pathfinder ('96-'04) has an R200A front differential. Theoretically, it should fit, but there may be slight differences in the way the axles attach to the diff that may make it a little more complicated than a straight bolt-in.

[silverton]

AFAIK, the r50's have an R200 front. But I'm not sure if the z32 has an r200 rear? I thought it was bigger, like an r233 or something like that?

[fleurys]

The front diff of the pathy is a high pinion reverse cut... So I doubt the 300zx rear diff is like this.... I would probably instead try to use the internals (friction discs and spacers) of the 300 diff and put it in the r50 carrier....

 

Anyway... good luck and let us know how it turns out.

 

S.

[XPLORx4]

If you really want to attempt this, you can try to see if the R200 LSD carrier will bolt up to the R200A ring gear. The challenge, though, is to understand how the front axles attach to the carrier. The R200A carrier may have a thrust block in the center of the spider gears that is used to bolt up the axles. The R200 LSD (since it is designed for a rear axle) may not have the thrust block.

[fueledpassion109]

thank you for giving me something to work off of.

 

I think the non-twin-turbo 300 is only a R200... I know its a good working diff as I drove it around before buying the engine (and diff for 5 bucks) (it was for a friends project) I guess I will need to pull the axels and check to see if they will interface. Ill check around the DIY area for removal tips...

 

fleurys - you mentioned its high pinion reverse cut. Ill need to see a rear VS front exploded view to make sure it can fit as guts only... which was what I was planning on doing. I could see it being an identical oriantation, just differance ring and pinion. great point, thank you!

 

 

Ill take some pictures of what I have and post them... maybe you guys will have an idea about the output splines

[fueledpassion109]

Just a small update, finding out that alot of diff internals are the same... between NA 300zx and path front axel.

[XPLORx4]

The R/P orientation is irrelevant to the operation of the differential. As long as the differential has the same number of splines, is the same diameter (i.e. bolt holes line up on ring gear), and has the same dimensions, the only thing I think you need to be concerned with is whether the driver's side axle will bolt to the side gear of the Z32 VLSD in the same way that it currently bolts to the side gear of the R50 R200A open diff.

 

Here are some other interesting threads to check out:

 

link 1

 

link 2

 

link with WD21 R200A diff exploded diagram (R50 R200A is slightly different).

[fueledpassion109]

so what I have is a 30 spline vlsd. I need to clarify that I will be gutting out my current axle. I only have the actual Diff its self. so if my current axle is 30 spline, and if the ring bolts to this diff I should be good. (i think ) as for orientation I was concered about the ring clearing the housing (from past r-awd m4 project that got scrapped)

 

Ill post my diff pic tonight

[MY1PATH]

I think before you go any farther you should be told that a VLSD WILL NOT perform as desired in a 4x4.

Viscous Limited Slip Differential, in other words it works off of fluid motion;

Its action is much like a torque converter requiring high speeds to activate the opposite end. In a car, the VLSD does not engage BOTH tires until at least one of them is propelling you ~30MPH but that's really based on DIFF RPM so in big pathy tires it would be more like 40+ before the VLSD transferred torque over to the loose tire.

 

 

What I would want (hopefully you do too) Is a CLSD or Clutch Limted Slip Differential

Its action is based off of a series of clutch plates pressed against each other. Its activation does not require any speed at all and some of them are designed to increase lockup when the input torque (not speed) is increased.

I believe these units can be found in 84-89 300zx turbo's and the will be identified by finned diff cover with the exception of the white SS Shiro edition which revived a vlsd.

 

Hope this saves from disappointment in the long run.

 

I might also add that in an R50 with permanently locked hubs and LSD will generate a level of under steer on the street. You can counter this by installing manual locking hubs and leaving the unlocked when you don't need them.

Edited December 16, 2011 by MY1PATH

[muddfildvaynes]

 

I think before you go any farther you should be told that a VLSD WILL NOT perform as desired in a 4x4.

Viscous Limited Slip Differential, in other words it works off of fluid motion;

Its action is much like a torque converter requiring high speeds to activate the opposite end. In a car, the VLSD does not engage BOTH tires until at least one of them is propelling you ~30MPH but that's really based on DIFF RPM so in big pathy tires it would be more like 40+ before the VLSD transferred torque over to the loose tire.

 

 

What I would want (hopefully you do too) Is a CLSD or Clutch Limted Slip Differential

Its action is based off of a series of clutch plates pressed against each other. Its activation does not require any speed at all and some of them are designed to increase lockup when the input torque (not speed) is increased.

I believe these units can be found in 84-89 300zx turbo's and the will be identified by finned diff cover with the exception of the white SS Shiro edition which revived a vlsd.

 

Hope this saves from disappointment in the long run.

 

I might also add that in an R50 with permanently locked hubs and LSD will generate a level of under steer on the street. You can counter this by installing manual locking hubs and leaving the unlocked when you don't need them.

[fleurys]

yeah that and at that point, I would simply weld the front and buy a set of warn hubs and be done with it.... You will then have a real locking diff and a street friendly truck with the hubs unlocked...

 

*good suggestion my1path *

[fueledpassion109]

oh I know and believe me I rather run a clutch type. all I carry is Kaaz, and carbonetics... both of which I cant justify spending 800 on. 4x4parts has some lockers I was looking at... but again $800ish. some drifters sugest putting in an additional washer to lock it down more. they seem to have good luck with them...

 

Any feed back on that additional washer?

[MY1PATH]

It may help by increasing how much it locks up and possibly at a lower SPEED.

But the truth is, unless you actually lock it, A VLSD will still be SPEED activated and not torque activated.

My buddy tried the washer thing in his 300zx VLSD and he cracked the housing because, unlike a CLSD, the internals are not meant to be pre-loaded.

[fueledpassion109]

are the 84 to 89 turbo 300's 30 spline? I was told the turbo diffs dont work. now is this becuase they are talking about the entire housing or just the Diff itself? Ill look around for a 84-89 300 diff. or ill just order one from car-parts.com. I will still install this one just to see the removal and install process.

[MY1PATH]

The housing is compeltely different.

[1994SEV6]

I'm lost here...

 

I thought the point of a LSD was to give traction to both wheels. That's why both wheels leave rubber when you do a burn out. BOTH wheels still spin.

 

If this VLSD isn't a LSD until 30mph, then what's the point?

If you try to do a burn out, you will only peel one wheel.

Going 30mph, you aren't going to randomly loose traction. It's not very likely, is it?

[01burgundyQX4]

You might read page 44 of "Nissan 300ZX The Enthusiast's Companion". It talks about the differential being used as a center diff in 4 wheel drive systems, but some industry engineers didn't think it would work well as an axle diff. Ford used one in the rear of some of their european 4x4's. The difference in rotation of two perforated plates cause the high viscosity silicon oil to stiffen. It is known for it's smooth and progressive action, and that is why it has been used in many sports cars. I've got one in my 300zxtt and I never notice it. I just have traction, (or not ) with both tires.

 

Today it is used in some crossover type all wheel drive vehicles, but the 300zx diff may be "tuned" differently and may not work well in your application.

Edited December 23, 2011 by 01burgundyQX4

[silverton]

I'm lost here...

 

I thought the point of a LSD was to give traction to both wheels. That's why both wheels leave rubber when you do a burn out. BOTH wheels still spin.

 

If this VLSD isn't a LSD until 30mph, then what's the point?

If you try to do a burn out, you will only peel one wheel.

Going 30mph, you aren't going to randomly loose traction. It's not very likely, is it?

 

The tires of a car will spin this fast during a burnout and activate the VLSD. Off road, you do not want this kind of activation, it's extremely dangerous.

[MY1PATH]

I'm lost here...

 

I thought the point of a LSD was to give traction to both wheels. That's why both wheels leave rubber when you do a burn out. BOTH wheels still spin.

 

If this VLSD isn't a LSD until 30mph, then what's the point?

If you try to do a burn out, you will only peel one wheel.

Going 30mph, you aren't going to randomly loose traction. It's not very likely, is it?

First, If Both wheels are planted and have near equal traction a VLSD WILL spin both wheels but on the trail( dirt, gravel, mud, lifted tire etc...) both wheels NEVER have equal traction.

Second, Burnouts are not a primary reason to install a traction device! But they may effect what type of device you choose.

 

 

Lastly, and here's the answer you really want;

At anywhere over 45MPH a car at the track can throw itself into a Flat turn. (as opposed to banked) If they make the optimal cut (as in the most efficient way to lead into the turn) the car will LITERALLY drive on 3 wheels as the suspension loads one side and no the other. Under these circumstances, if you had an open diff, the grounded wheel would have all the traction sending all the torque to the lifted wheel. In a split second your RPM's would spike(and your lifted wheel speed would increase) the car would lose its speed, drop down onto the free spinning wheel (that is moving too fast) and throw the car into a counter turn.

 

 

This is EXTREMELY DANGEROUS! cars have spun, flipped and drivers have been killed because of this.

 

The VLSD was invented for the reason above and for longevity in track use. Clutch type LSD's wear out fast at the track, they don't like all the heat combined with hairpin turns and if set to tight the cause under steer. They also work in drifting because both wheels are spinning so fast.

[Kingman]

Hold on a second. The CLSD in a Z31 was offered from 4/'87-'89 TURBO cars only! Never NA, and not before 4/'87. And because of that they are worth a mint, bout $500-800 from a seller that knows what they have. VLSD is garbage.

 

Being an R200 it'll swap right in to the Pathfinder carrier.

 

Here's a copy from part of a local Craigslist ad

87-89 R200 CLSD 3.70 turbo 300zx with finned cover and CV axles $800

Edited December 27, 2011 by Kingman

[silverton]

The SS(?) 300zx that was offered in 88 had a VLSD if I remember correctly.