6.2L & 6l80 Power Uprades

[guruerror]

Originally Posted by ryaleon

This is all great info. I will most likely regear. What do I need to know about this? Is it too much for a home mechanic to do? Where can I get parts?

I got mine at Trail Duty: https://www.trailduty.com/index.php?...c27c864fc4998f

You'll need the fronts, rears, and an install kit.

It's hard for me to comment on the install since I had the shop do mine, but I think if I had the 'time' on my hands and knew that I had the appropriate 'tools' that I could have done them; there doesn't seem to be anything obvious that jumps out at me as being super difficult. Surf YouTube for instructional vids on swapping gears in a H2/2500 4WD or similar...that should give you a better idea.

Originally Posted by MVR 155

Stock GM tuning leaves quite a bit on the table, I would love to tune my truck but I have a GMPP major guard for another 2.5 years that I don't want to be voided. Check out Nelson performance, highly recommended for GM trucks.

Another thing..... for the guys with the 2003-2007 trucks suggesting 4.88 gears..... The 08/09's stock have 3.73 gears vs. 4.10's that come in the 03-07's. That is a major jump in gearing for a tire that is only about 2 inches taller and will certainly have you turning some high RPM's on the highway. Going from a 3.73 to 4.88 will have you going from about 1700rpm on the highway to over 2200 (assuming approximately 75mph). The 6L80 also has a very steep first gear ratio of 4.027 which could make for some jerky driving at low speeds. Before jumping up that much I would see if you could talk to someone who has done this in a 08+ truck.

Which is why I recommended the gear calculator (http://www.4lo.com/calc/geartire.php) it'll let him compare various combinations to stay with a stock final ratio and keep the truck in it's powerband.

[ryaleon]

Seems I would be better off with 4.56 vs the 4.88. 4.88 seems like a huge jump from 3.73.

[ryaleon]

seems like it would close to $900 or so for parts if i were to order myself. I'm assuming about the same price for shop labor.

The gear calculator says that my effective ration right now is 3.53. says new gears 3.94, low gears 4.3, and high gears 3.59. Im looking at getting closest to the low gears right?

[guruerror]

Originally Posted by ryaleon

seems like it would close to $900 or so for parts if i were to order myself. I'm assuming about the same price for shop labor.

The gear calculator says that my effective ration right now is 3.53. says new gears 3.94, low gears 4.3, and high gears 3.59. Im looking at getting closest to the low gears right?

Lower gears will give you more take off and umph...but will increase the RPMs on your top end. Seems like 4.10s would put you closest to the stock power band, but that sucker will prolly jump off the line with 4.56s.

[ryaleon]

Then I think 4.56 is the way to go. I'm not concerned with mpg much....it's a Hummer after all the price of gas pays my salary so not an issue for me. I want it to be torquey! I'd like the deuce to be quicker than my dads 6.7 Diesel F250