Thats a tough think to say... Genuine 80 mph i think it would work fine.. There has been no issues with mine.. But I also put a MAG-Tec diff cover that let me fit an additional two qaurts-ish of fluid in it... sooo.... mine doesn't have any issues but i'm not 100% positive about it in general.

I think I'm just going to get the LS that's in the truck rebuilt I think the clutches are burnt out in it and just be done with it, it won't be but about a 100 so a lot cheaper lol but just curious how do the 4.56s for at high speeds ? Could you run 80+ and still be fine ?

Yea my Yukons are still doing great. I'm not driving them right now but my uncle is. I'm still in afghanistan. But they are working out fine. Are you going to do the LS or Lockers with it?

Hey man I'm bout to swap my gears out! Just wondering how yours are holding up and if you still are happy with them?

You will notice a difference. Too bad you don't wanna go with 4:88s.. But i think if you ever wanna drop down to 35s it would be better to keep the 4:56 gears.

No not yet it won't be long hopefully this month ! I'm ready to get them for sure ! I've decided to go with the 4.56s!

You change them gears at yet bud?

Most people will tell you that the TrueTrac is the most Aggressive limited slip on the market. And with the suspsension flexed there is no change in any form of LS, Posi, or locer.. They just distribute the torque to the wheels. What i liked most about the TrueTrac is that it is all gears.... There is no maintenance on it... True a posi-trac might be more aggressive but it will eat your tires up on tires on the highway... i think the true trac is the best of both worlds.

Y eag I would def. do the whole set up all at once! How does that true trac do when the truck is flexed? Will they both still turn?? And just so I'm correct this is just a more capable limited slip correct?

I know but that lil pie will turn your two wheel wonder into an offroad beast. The main thing is to do it at the same time your doing the Ring and Pinion so there is no additional cost. I would just save until you could do them at the same time.