Trac loc or whatever

I have a 2005 F250 Power Stroke 4x4 with the factory "limited slip diff" The other day while feeling my "oats" I power jacked it and did a burn out for some 80 feet..sadly I see only rubber on the passenger side ... one tire fire...what the hell is going on?
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Have you jacked up the rear of the truck and checked to make sure both tires turn the same direction when rotated by hand?
If they do turn the same way, you probably have a loose ( too much freeplay) clutch pack in the diff.

Check Ford-trucks.com

You will see tons of posts like this. The ford LS needs a bit of torque before the clutches lock. Just stepping on it might not work. (mine won't spin both doing that - 2001 V10)

If I step on the brake, give it some gas, then let it go, both tires spin.

Drain your fluid and refill but don't add any LS additive. Drive it. If it's too harsh, add a Little bit, like 1/2 an once at a time until it's acceptable.

Overall I'd say it's a worthless option. I wish they offered a real locker like just about every single other truck manufacturer out there.
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