BrianHeston

The two times that I got stuck in the snow that we just got through with I noticed something strange. Even though the car was in two different positions, as far as balance and suspension load goes, it looked as though the right rear was the only tire spinning. I can't confirm this for certain because I had no one outside the car to watch the tires. But, the right rear was the only one that dug itself a hole each time, so I figure the left wasn't spinning too hard if at all. Is this normal? Shouldn't the LSD cause the left to spin once the right begins to spin freely? Or am I completely confused as to the functionality?

Thanks for putting up with the novice question, and long preamble.

Brian

Junia

what model do you have? The only ones with the lsd are the GSL and the GSL-SE.......I think

Lotus00

hes got an 82 gsl. says it in his sig

Steve Shulz

Wasn't that snow fun! I'm glad its gone. Not sure of the function in snow/ice, should have dug two holes I would think, one may be deeper but would think two holes.

RoyFifo

It's time to rebuild your LSD.

I need to rebuild mine as well as it does not lock until I get to 3K in first with the passenger tire slipping.

Racer79

Well, I've got a 79 GS,so I'm not sure if I had an lsd, but it sure felt like it off the line earlier this year. Now in the snow, I've come to realize the same thing happens, only one tire spinning.

Is it worth rebuilding or can you upgrade the rear end? What kind of power should i be making to make it worth an upgrade?

Steve Shulz

Racer79, by default unless someone upgraded yours you have an open diff so your answer would be to upgrade 83+ GSL and GSL-SE's.

Racer79

Hmm ok, if I was planning to make say 250+ hp eventually, would that diff suffice?

The_7

yea im pretty sure they are good for well over 250hp

MarkPerez

The rearends aren't bullet proof and wouldn't push it
over 200 HP without doing some major mods. These cars
use a 'live' axle. rear wheel drive with a 3rd member or (pumkin) to change the pumkin one has only to pull both axles,drive shaft,and unbolt the pumkin from the rearend housing. either your LSD is fried or has been changed in the past. believe it or not,,, one can have a LSD with drum brakes on the rear. all you do is change the pumkins. but remember to try to stick to your year car because the axle diameters are different for 84-85
83-81 that i know of.in other words,, say you have an 1982 GS, use 1982 GSL pumkin.

QuagmireMan

blew my pumkin to bits about a month ago. not sure how many ponies i have but i cant imagine im close to 200 yet. it took me forever to find another LSD rear end.. and the LSD rear end helps alot when your losing control, as i found out tonight

theweasel

I may have an extra one for sale. Will know tomorrow. If anyone is interested?

BrianHeston

Thanks for all the info guys. I thought that was going to be the case, just wanted to make sure.

Brian

'85 GSL 302

I'm running over 230whp and my rear end is holding up just fine. I know many people that run 300+ whp and don't have anyproblems. It matters more how much torque and stress you're putting through it. If you screw around on the street on 195 all season tires, you have no problems, because your tires will lose traction long before your rear end should break. Now, pulling 1.6 60's on slicks at the strip will kill it no problem. I run 1.9's on mine when I take it to the track, and so far I don't even see any wear.

Now to answer your question, the LSD should cause both wheels to spin, however, the nature of factory LSD's makes this dificult on two different surfaces. Because they're clutch differencials, in certian situations they won't work. If for instance, you have one tire on dirt, and one on pavment, you will only transfer a small amount of power to the pavment, because the clutchs are basically overwhelmed by the large difference in traction diferences. These LSD's aren't designed for off roading, just racing. A gear type LSD would offer constant power to both wheels, but the downside would be if you removed the load from one side, you would damage the unit. IE: if you have one wheel in the air, or even on ice, you could cause damage. A viscous unit actually grips more the more it slips, and would be the best choice for you if you live in constant snowy areas. The down side to them is that they don't start to work unit after they start to slip, so in autoX situations they can lead to unbalanced cars that suddenly change characteristics.

Now in your situation it's hard to say what happened. It sounds to me like you are in need of a rebuild. If both wheels were on the same surface, they should both spin. A good way to test this would be to turn the wheel, and dump the clutch at 6000rpms. If the back end jumps loose, you'll know your diff works. If it just boils the inside tire, your looking at a toasted LSD. Or you could just jack the car up and have someone hold one wheel while you turn the other. You should have a noticible resistance. If it turns freely, new Diff. time.

BrianHeston

Yeah, I figured I'd do the jack up and spin test before I jump to any conclusions. I know I can get it sideways fairly easily, but have not done it from a stand still for a while other than on a slick surface. Thanks for the detailed info '85 GSL 302.

Brian

1stgen4life

iTrader: (1)

weasel, how much are you looking to get?

RotorMotorDriver

iTrader: (1)

By the way, an old 4 wheeling trick I know for LSDs is that if you get semi stuck (as I did in the snow and this helped A LOT), you can set your parking brake a small (or large, depending) amount to help provide resisitance to both rear wheels, thus making them both turn together. The downside to this is that you can no longer "rock" the car out of the situation, but if you are fairly in tune with your car (or fairly hand/foot/eye coordinated), you can make it work to your advantage. I for example was able to hold the button on the parking brake and pull it up and get the car to move forward, then let it off to roll backwards and then pull it up again as I tried to go forward again, thus rocking the car and finally driving out after a mere 30 seconds or so.

~T.J.

theweasel

1stgen, how about 150? or??

'85 GSL 302

That eBrake trick is a great idea. I never thought about it before. Good info.

MarkPerez

that works for non-posi's too.