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Old 04-16-2002, 07:52 PM
blykins blykins is offline
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I know the Trac-Loc in my father's '97 Mustang Cobra is mashed together pretty tight all the time. It probably varies from car to car...there are actually springs and shims that keep a preload on the clutch packs. I know when backing out of a gravel driveway, you can just let the clutch out quickly and it will spin both tires. There has to be a certain amount of preload for the clutches to be tight...and there has to be a certain amount of tolerance there so you can actually turn a curve without bouncing the hindend around.

From your description, it sounds like it may be quirky. A Trac-Loc diff doesn't really "lock." It just has constant pressure between the clutch discs inside. The faster you spin the diff (i.e. acceleration) the more you get centrifugal motion pushing the clutches together. Of course this makes them even more tighter. But they should always have a certain amount of preload. And of course in a curve, the clutches are gonna slip a little, or you'd have trouble going around the curve. As for your turning in when you let out of the gas, that's about normal for most cars. Anytime you're in the gas, weight is transferred to the back tires...causing you to have to input a little more steering than usual. As soon as you let out of it, the weight falls back on the front of the car, putting more emphasis on the front tires, causing them to bite a little harder and turn you in quicker. That's why 911 drivers used to have so much trouble with trailing-throttle oversteer...all that weight is shifted to the front tires when they lift...causing a severe turn-in.

What kind of caught my attention is that you said you could "feel" the diff locking and unlocking. That seems a little out of the ordinary. Usually you can't feel them at all like say a Detroit Locker... Is it noisy?

Hopefully I've helped answer a few of your questions. I may have misunderstood you about the turn-in though. I've been known to do that from time to time. : )

BTW, are you using a friction modifier in your rearend grease? There has to be an additive in there to give the clutches a little friction...else they would slip a lot.

Brent
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