Before I drop 3K on trans upgrades, I was wanting to put a 6" lift/37's on. On my old truck (00' 2500 6.0L w/6" procomp, 3"body lift) it ran like a dog with 37's. My question is if I put a lift and 37's on, will my duramax still run, or will I have to re-gear to still have power.

Some will say you will have to re-gear, I think if you add the lift and do trans upgrades, with the right power you should still be fine. If you are going to use your truck to pull at all then you will probably want to re-gear... Good luck

Thanks for the info GMC2500HD Where is the best place to buy RCD lifts.

Ive Got A 14000# Bumper Tow Trailer That The Truck Pulled Like A Champ With Stock Tires. Verry Little Shifting Up Hills Etc. Now With Lift And Tires It Still Pulled It, But Of Cource, Speed At Top Of Same Hills Was Less And Tranny Would Come Out Of Od Trying To Maintain Hwy Speed. This Was The Reason For Power Upgrades. Snow On Ground Here And Have Yet To Pull Trailer.....outcome Unknown.....

Most Of My Customers Than Put A 6" Lift On There Diesel's Do Not Regear Just Add A Little Power. Trans Upgrade Is Also A Good Option. I Even Have A Truck We Did With 38" Tires And He Tows A 30' Trailer And Says It Stills Tows Good, That May Be A Little Extreme.

Where Do You Live? I Sell Rcd Kits And Could Ship To You. Pm Me For Details. Are Putting 37's On Just A 6" Rcd? If So You Will Have To Do Alot Of Triming To Get Those Tires To Clear. Cst With 2" Keys (to Make 8") Might Be A Better Choice But It Also Depends On Your Wheel/tire Combo.Yea i was thinkin the same thing but my friend has a 01' duramax with a 6"RCD and Goodyear MTR 37's on 8" rims. He did a little trimming, but for the most part no, or very little rubbing.

You might want to talk to RCD and find out who they would suggest in your area... Good luck..

with a 6 inch rcd it will be close with 37's, like you are going to have to crank a good deal, i think you would be better off, and beter on your cv's if you went a little bigger, like a cognito 7-9 or a cst 8 inch kit, both of these you would clear 37's without any cranking, and i think they are a more quality kit than the rcd imo

I would be worried about egt's w/37's if you tow, if you do not regear. If you don't tow the egt's wouldn't be an issue.

Also, without regearing you are going to feel slow. I have a couple friends with dmax's. Two of us have 6" lifts and 315's and stock 3.73. I have hypertech and he is stock. I am much faster in all repects to him. Towing or unloaded it is not close. But another friend has stock tires, height, engine and he takes me with no problem.

Because of this and I want a little lower egt's when towing I will be regearing, even with the 315's, this spring.

Also if I had to do the lift again I would have gone with 8". This truck is just so low that with the 6" I am closer to 4" on Dodge and Fords. I don't even have a step bar and it is easy to enter and exit the truck.

get a cst 6-8". it drops the diff 6" as opposed to the others that only drop it 4". then if you want 8 you just crank the t-bars for 2 inches and your cvs will be within spec. also i would definately regear it. my friend and 35" tires and 3.73 and it feels slow no matter how much you are on it.

What about procomp/superlift? I had a 6" procomp on my last truck. Not a bad lift, but a pain in the Censored to install.(Got tired of drilling 3 holes through the frame for each upper arm drop) I believe they have 6" diff drop.
How much for the CST? I don't want to drop more than 2K on a lift

What about procomp/superlift? I had a 6" procomp on my last truck. Not a bad lift, but a pain in the Censored to install.(Got tired of drilling 3 holes through the frame for each upper arm drop) I believe they have 6" diff drop.
How much for the CST? I don't want to drop more than 2K on a lift

Go with RCD then, you wont regret it.

I don't want to hijack someone's thread, but who makes a lift for a 2005 3500 besides RCD? (No duals, single rears)

I think you'll be fine......I tow with stock gears and 39.5s and even on hot days it never gets too 1400 and I have a very heavy foot. I actually like the feel of having longer gears and shifting less.

SKYJACKER just came out with a really nice kit for the 2500HD's....Couple of people at work are looking at them real hard. I am willing to bet its probably a dam good kit. You never see anything but a sky jacker typically on trucks for the serious 4x4er's.

http://www.skyjacker.com/products-02chevykit.asp

I am going to look at this kit as well. I am not a real fan of CST ...I watched my brother in law twist the **** out of one on a brand new 1500HD (aka 2500 with 1500 badges). The dealer ended buying the thing back because it was all jacked up. RCD I know and heard makes a good kit too....With all of them the only thing i worry about is tearing up CV joints. Something to consider....if ur willing to toss 3000 dollars maybe its worth going to a live axle. We purchased these 40-$50,000 trucks to run not to break because we got cheap. You want it to run and play hard with you not leave you stranded...My 2 cents......to each his own.