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lsd shot?

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Old 12-04-03, 09:55 PM
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Angry lsd shot?

im thinking its gone..

im not one to be a jackass in parking lots.. but today a couple of my friends from my auto tech class were all like "i dont think you can burn out" and stuff like that.. so i was like.. alright, ill slide sideways out of the parking lot... i was going, reved, dumped, and the inside tire spun its *** off, and the driver side tire just sat there.

a.) i looked like a jackass
b.) i looked like i couldnt drive
c.) the f'n rear didnt come out like i wanted

i mean, its not like im a bad driver, i autox'd all last year, and went to a couple US Drift events. but do you think my lsd is shot? i heard that if yo udont have fresh fluid in it, the clutches will slip. you think i could just replace it and get nicer fluid like redline?

i know before the last drift event i went to, i checked my diff. fluid, and it was really low, but i added to it. i cant check it now because its wet, and im not trying to go under the car on the wet *** ground...

this blows


edit: the rear end came off a gsl. i dont know the year, but the previous owner said it had 60k on it when he put it on, and that was ~10k miles ago..
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Old 12-04-03, 11:51 PM
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A 60k GSL rear? Man that's rare. There are a couple ways you can tell if the LSD is shot. One way is to do cut the wheel sharp and drive in tight circles in a parking lot. The turn radius should be pretty tight compared to that of a VLSD or open diff. Another way is to locate a back road with grass/dirt on the side, stop the car with one wheel off into the grass and then floor it. You should take off pretty quick if the LSD is good. Take care when doing this so you don't loose control for whatever reason. Also, not having other drivers around is a plus.
Anyways, I never really heard much on recommended rebuild times on a LSD rear except for Tsuchiya's D-bible video. According to him, if you drift often, like 3-4 times a week, he actually recommends an overhaul once a year. That seems pretty often to me, though...
And yes, good fluid like Redline can breathe new life into old stuff like that. LSD additive would help too.
Oh, and no fluid in a rear will mess it up bigtime. Depending on how long it's been without fluid would determine how damaged it is.

Last edited by jayroc; 12-05-03 at 12:16 AM.
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Old 12-05-03, 12:12 AM
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Okay, I just watched D-bible again and Tsuchiya says 'if you drift 5 days a week, you should 'overhaul your LSD once a month or so'. Whether or not he means a complete rebuild is not clear, but changing the fluid doesn't really qualify as an overhaul to me. I never heard of anyone rebuilding their rear anything close to that often. Wouldn't be a bad idea to change fluid once a month if you drift often, though.
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Old 12-05-03, 05:25 AM
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From a previous thread:

Originally posted by pineapple racing
To test the lsd, jack up only one tire off the ground, block the car so it cannot move. With the tool you have make, a piece of steel with holes cut in it to fit over the studs (or bolted with lugs) with an old socket welded to it with the 1/2 in drive end out, use a beam type torque wrench and see how much torque it takes to rotate the "wheel" that is off the ground. 85ft.lb. is a tight unit, probably a recient rebuild. 30 ftlb. is common for a used street piece. The hardest part, is putting the ring gear back exactly where is was so the pattern of the gear contact is not changed. This could cause gear noise. In sever cases reducing the life. The friction plates are not too pricey, and they don't all need to be replaced. Even if it costs you a little more than an untested used unit, it would be rebuilt not used. Someone that knows them will probably not charge more that an hour of shop time+parts to freshen just the lsd if you have it out of the car and clean. If you do it yourself follow the book, clean all the bolts/bolt holes very well and use locktite on every fastener. If you use the original ring gear check the back lash BEFORE dissassembly and return it to the same figure. For the bearing preload, check how much torque it takes to rotate the assy. before you diss. then put it back (I usually add a little more drag to make up for normal wear). Don't add to much! Rob
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Old 12-05-03, 06:06 AM
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Good stuff Bob.

One more tip (one I have not tried). I hear from reliable sources that you can fit an extra clutch pack into the LSD by lapping the other ones. Maybe even keep you existing worn ones since they are already thinner and add to it. This will result in a very tight LSD.
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Old 12-05-03, 10:37 AM
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Anyone else have one that is so tight when cold that the front wheels slip when on full steering lock?

In the mornings when I drive out of the subdivision, making several 90 degree turns, the front tires tend to push and skip across the road surface. This goes away when it is warmed up.
Really notice it now with temps around freezing.
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Old 12-05-03, 11:28 AM
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Originally posted by Bruceman
Anyone else have one that is so tight when cold that the front wheels slip when on full steering lock?

In the mornings when I drive out of the subdivision, making several 90 degree turns, the front tires tend to push and skip across the road surface. This goes away when it is warmed up.
Really notice it now with temps around freezing.
this is what we call understeer. lol

as for the LSD...mine has 250k miles on it, and can STILL do donuts like a vette! just take care of it (replace the fluid) and it should be ok.
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Old 12-05-03, 02:38 PM
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My LSD is so tight that the inside tire chirps on a 90 degree turn upon acceleration and i have been asked on several occasions whther i have a welded diff or a spool LOL, and whenever i drift there is none of the wondering "is it going to posi this time?" like i have had in the past with other worn out diffs. Just glides to the side till i let off the gas.
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Old 12-05-03, 03:34 PM
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lol i luv my lsd too bad my rx7 has one and not my rally car (sad i know)
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Old 10-29-05, 09:28 PM
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do you reccoment adding the lsd friction additive ?? because i jsut have regular 80 90 gear oil in mine oil is fresh but no additive thanks
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Old 10-29-05, 09:34 PM
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My Lsd was chattering really bad when I got the car. Drained the fluid and replaced it with new gear oil and LSD additive and I haven't had any problems since.
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Old 02-10-12, 12:44 AM
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this thread is very helpful.
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Old 02-10-12, 08:48 AM
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100% of my friends who know anything about cars are super jealous when they find out my 1981 POS has a lsd and their cars dont
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Old 02-14-12, 10:04 PM
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And old thread but a goodie!

When the diff is shimmed real tight the rear of the car will hop on tight parkinglot turns. I bought a LSD with 4.444 gears and it was rebuilt tight. REAL tight. Measured the breakaway torque at over 150 ft/lbs. My torque wrench goes up to 150 and it still didn't pop. Damn nice. Stock is 90.
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