I would highly suggest you use nothing but AAM gears. The cost difference from aftermarket gears is insignificant when you buy from Ron's Machine Shop (don't buy from anywhere else). AAM 4.10s and a Detroit Trutrac is what I recommend and what I run. It worked great for me at the track.

 

If i were to do gears, id stick with AAM as they are the company that makes them for GM. I have 200k miles on my stock 3.42s.

4.10s would be your best bet for the 1/4 mile and around town and slight off roading.

 

I have stock [AAM] 3.73 gears [front and rear] that I would sell cheap if you go that root.

 

Regarding AAM gears, I've also read that they are heat treated to 1500 degrees from the factory. This pretty much negates any requirement for a 500 mile break in period IMO since 1500 degrees is much, much higher than the temps the gears will see in the pumpkin.

 

Well guys around here it's $1600.00 for front and rear parts and labor. This is new bearings including the axle bearings. And this is not including a better locker. I have the G80.

This is the best price I can get from a known good shop. The truck will be paid off in November so it looks like it will be after then. The local GM dealer says $2300.00.

You guys are influential on the 4.10's but my gut says too tall for my application so I may compromise to 3:90's?

 

Well, I cannot find an AAM 3.90 for the front. So........

 

they dont make them. I'd just stay with what you have. Too much cost to swap.

 

No such animal from AAM....it's either 3.73's or 4.10's.

 

Ah! In the mean time I am studying this chart

The next tire I will run will be the Michelin Cross Terrain "H" speed rated @ 31.9". 265/70/17.

 

i would never recommend that tall of a tire with 3.42s. My 6.0 was a turd with 3.42s and 31"ish tall tires. It would cruise @ 60mph @ 1500 rpms.