so here i was looking over the truck and on the hood underneath theirs a sticker and says factory lsd.. looking at my build sheet says.....

Shift-on-the-Fly,231HD Transfer Case
195MM Front Axle
3.55 Axle Ratio
Corporate 9.25 LD Rear Axle
Anti-Spin Differential Rear Axle


so i take it i have a factory lsd then?

 

Yes, you have LSD.

 

Power brake your truck and then go look at the marks if you have 2 lines you have LSD

 

Nice.

 

very funny red.. well guess i need some lsd additive when i do the rear fluid change was gonna go amsoil or royal purple fluid.. anyone have a recomendation on the lsd additive?

 

Hey it works, in high school we used to do burnouts in the parking lot to see who had "posi" or open differentials needless to say a lot of people that said they had posi were very wrong, Most of the oils I found had the stuff already added, but any brand should be good

 

Jack up the rear end of your truck. Spin one of the rear wheels with your hands.

If the other wheel turns the opposite direction, you have an open differential or a broken LSD.

If the other wheel turns the same direction, you have a working LSD.

 

The powerbraking test doesn't work. I have seen many times where both tires can spin with an open differential. In fact, I've had it happen back before I installed a LSD.

If both tires have equal resistance, they will both spin with an open diff. The only way to test what kind of differential you have by driving the truck is put one tire in the dirt and one on clean pavement.

 

I agree, my open rear end has spun both tires on pavement on several occasions.

 

No, No. Jack the rearend up. Get a buddy. Have him hold the right wheel, and you turn the left...HARD. If his wheel spins while he is trying to hold it still...then it is LSD.

EDIT, just remembered, he might feel like the tire is goinmg to move, then as he hoolds it still, it might SLIP and he will not feel pressure for a second.

THat is the SLIP part of the limited slip.

--Dan