I opted to have someone else install the lift. I was going to replace the gears but got talked out of it by several people. I wish I had gotten it all done at one time. I would have saved time and money. I may replace the gears but I am still unsure what to install. I have 3.55 now, a fabtech 6" lift, and 35" ProComp All Terrains. I love the tires! Super quite and great ride. I spend my time on the road for the most part. Weekend vehicle that spends some time on the highway but mostly local driving and some towing. 4.56 has been recommended by many. Wayne at diffs only quoted me a good price on the 4.56 gears and install kits but, before the truck went in for the lift install, he thought maybe 3.73 would be good. I am clueless on this stuff. I did buy a CTS programmer that I will install soon. I have been told to use the programmer and drive it for awhile by several people. Any advice will be appreciated. I really want to be able to enjoy this truck for years to come. Gas mileage and performance are top priorities.

 

those two should never be in the same sentence!

well, how do you like the truck with the 3.55's and 35's right now?

i drove with that combo for almost 4 years.

 

So far I have noticed little difference except when I attempted to go over a steep bridge. It definitely lacked some power. I purchased the Edge CTS programer and will install it as soon as I can. I also bought the back up camera for trailering and backing. I have kids that may need to drive the truck and that will be a plus. I will let you know how it performs after the programmer is installed. Why did you go with 4.88 gear ratio a instead of the 4.56 ratio?