The AUSubaru.com.au Forums

Hey all.

This question may have already been debated... which is better 4 off roading - clutch LSD or Viscous LSD?

I'm after one of these to avoid the stuck-on-diagional-wheels-off-ground effect that occurs more than once while off road...

All ideas/opinions would be good.

Cheers

i dunno, but i just got a clutch lsd, makes a friggin massive diff(jokes), especially in sand..forward nuts are now easy

alex

u need more power to whip em properly alex hehehe big circles lol

This gets a lot of people fired up, as people have had good and bad runs with both.

My personal preference is with the viscous units because they're low maintenance and I've found every one I've owned to be quite tight. The clutch packs are good too, when they're tight they work very well offroad, however once the clutches are worn they're no better than an open diff.

Welded diffs are great offroad too, and a cheap alternative to a proper locker. A detroit style locker or an air locker would be a whole grade above the rest when in the dirt. Remember LSD's are just that - limited slip differentials. No true locking in the equation.

Now we'd all love to get out hands on Lockers (not the welded kind either) however to answer the question i am a VLSD person - this being said though i have never owned a clutch type

I found in Issue 92 in 4WD Monthly magazine an article on how to re-shim a clutch LSD.
Its an early Pajero item, but the principles still apply for those interested.

very interested Subanator... please make a new thread about this.

Dave

In theory the Viscous diff should be better than the clutch one due to the way they are made. There is an article floating around the internet that shows a comparison between a number of diffs. It also explains how they work. I will have a hunt and see if I can find the one I am thinking of.

Until then here is a few links of interest.
http://www.quaifeamerica.com/differenti ... f_apps.htm
http://www.quaifeamerica.com/differentials/diffs.htm

http://www.4x4abc.com/4WD101/ls.html

I have had both styles of diff over the years but unfortunately never in the same car so a comparison is difficult. I have had different viscous diffs in the one car. The one I am driving now I am talking about. I have swapped gearboxes that have had different ratios and so had to swap rear diffs.

I had a 4.444 diff in there until the box broke and I fitted a 4.111. I thought with both rear diffs being viscous there would be do difference in the way they worked offroad but there was. I don't know why but I am trying to find out. Maybe it is simply that one is buggered.

SuBaRiNo wrote:very interested Subanator... please make a new thread about this.

Dave

Best option here is to order a back order copy of this mag via their phone order (listed in mag for details). This article has more pics than written content etc.

Jaffa wrote:Now we'd all love to get out hands on Lockers (not the welded kind either) however to answer the question i am a VLSD person - this being said though i have never owned a clutch type

Hey Jaffa when did you get the VLSD unit? I gotta get one of these myself...
I always knew you had an LSD but I thought it would have been a Clutch type (transferred from your original RX)?

Yeah i assumed Jaffa had a clutch one too... RXs all had clutch ones right??

Dave

Yes, RX's all had the old clutch type of LSD. Viscus units didn't come into Subaru's until well after the L series era I beleive.

I think Jaffa is confused and he has had a clutch pack all along.

Dave

Yer sorry dums ass Jaffa posted incorrectly (once again)

Reminder to everyone.... Oversteer came up with a great way to bolt WRX VLSD's into an L series.
Previously you had to mess around dismantling them, separating the ring gear from the centre and swapping the LSD centre into an L series casing.

Instead now you can just get the stub axels off the side of an L series casing, get a snap ring groove machined into them (less than $100 at a machining shop) and pop them into the side of any late model WRX diff to convert it from female to male stub axels. Then it will bolt straight in without even taking the rear cover off it.

AndrewT wrote:Reminder to everyone.... Oversteer came up with a great way to bolt WRX VLSD's into an L series.
Previously you had to mess around dismantling them, separating the ring gear from the centre and swapping the LSD centre into an L series casing.

Instead now you can just get the stub axels off the side of an L series casing, get a snap ring groove machined into them (less than $100 at a machining shop) and pop them into the side of any late model WRX diff to convert it from female to male stub axels. Then it will bolt straight in without even taking the rear cover off it.

Depends... on VLSD needs an longer stub axel on left side and right side is shorter than other. if the longer one is broken or replace to short one, then the LSD will become open diff.
Cheers
AP

Here is the pic regarding my previous post -


Its off from RS Liberty VLSD.
Cheers
AP

Yeah but I was talking about the later model diffs which have female outputs. ie no actual stubs sticking out. Can put L series ones in there solong as they have the snap ring groove machined in I beleive.

AndrewT wrote:Reminder to everyone.... Oversteer came up with a great way to bolt WRX VLSD's into an L series.
Previously you had to mess around dismantling them, separating the ring gear from the centre and swapping the LSD centre into an L series casing.

Is it possibe to get a WRX LSD and change the ratio back down to what's in my gearbox? I've been wondering if it's possible to change the R&P gears to the L's leaving the LSD centre in there... Or taking the centre out and swapping it with the one in the L casing (strenght issues?). I realise either way it would be a diff pull down...

Any opinions? (like i have to ask...)

Cheers.

I think what you'd have to do there is take your L series housing apart, separate the open centre from the ring gear. Then get the VLSD centre from the WRX diff and put your ring gear on it, then put that all into your L series housing.
I havnt done this with a WRX one so not 100% sure if everything will fit together.