I'm new on this forum so I thought I would "give" a little before I "took" a little.

A year ago I was having a problem with my rear differential not slipping, and discovered I was not alone (from some forgotten forum way back then). Back then, I read that many truck owners were having problems with their limited slip rear ends not slipping when turning.

The standard answer I read from other forums was to add more conditioner to the differential fluid. (and more, and more, and more).
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Being the cynic that I am, I asked a coworker, that was a professional race car driver, about my problem. As a fellow F150 owner, he knew exactly what I was talking about.

The problem arises because we spend so much time driving in a straight line (like freeways and off-ramps) and making gradual turns, that the clutch pack in the differential sticks together (like lifting your foot out of the mud and having your shoe get stuck behind).

As complicated as the fixes have been on other forums, it is actually quite simple: Re-wet the clutch pack. (Assuming you already added one bottle of conditioner.)
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Well, re-wetting the clutch pack is a very long and complicated procedure that only a highly trained individual can do. The risks are very high, as the whole truck can explode in a tremendous fireball.

If you're not afraid to try, here it is:

1) Find an empty parking lot.
2) Make several tight circles to the right.
3) Make several tight circles to the left.

If your truck didn't explode in a fiery catastrophe, then you successfully re-wetted the differential clutch pack. (Oh, if it did explode, then I guess I owe you an apology.)

 

 

Ridiculous

 

It's not looking good, powertoolman!


hehehe

 

i like you (but i'm not gonna invite you home to help me with my repairs)

 

You could also stop on the edge of the road with the left rear wheel on the road and the right on the dirt. Hold your brake and step on the gas. After the clutches wear a little, they will release easily.

Just Joking!!! This is the way to wipe out your clutches.

There is a TSB on this problem. The factory fix is to change out the clutch pack and shim it 10 thousandths less.

 

What's reasonable to have to pay for replacing the clutch pack in the LS rear end? My friendly Ford dealer quoted me $1000 if that's all it needed...

 

Tell your local friendly dealer to go somewhere and do certain things when he gets there. You could probably change out the clutch pack yourself, since it does not involve disturbing the gear settings.

 

Despite all the sarcastic replies on this thread, the original poster has some good advice. The fools are the ones paying hundreds of dollars for unneccessary repairs without trying the donuts in the parking lot first.

 

so if you're gonna add conditioner, what do you need to do first? drain a small amount of fluid from the rear axle...? or not worry about it?

 

No need to drain anything, it's only 4oz.

Put it in through the fill plug and drive until it takes effect.

Good luck.