Timbren Suspension Support and Rear Lift Options for a 2003 Chevy Avalanche 1500 4x4

Updated 10/16/2026 | Published 10/14/2026

Question:

2003 CHEVY AVALANCHE 1500 4X4. I HAD A PLOW INSTALLED AND THEY ADDED RC 1.5-2inch KEY LIFT ON FRONT FOR INC GROUND CLEARANCE. NOW WHEN PLOW IS OFF THE VEHICLE RAKES TO REAR. I WANT TO COMPENSATE THE REAR HEIGHT BACK TO FRONT RAKE WITH NO PLOW AND ALSO WANTED TO ADD TIMBRENS GMRG25C TO HELP REDUCE REAR RAKE UNDER A MAX VEHICLE LOAD. CAN I USE THE REAR TIMBREN GMRG25CS WITH THE T33AV...OR SHOULD I NOT, WHAT ARE OPTIONS TO ADRESS BOTH RAKE AND LOAD SAG? THANKS!!!!

asked by: STEVE M

Expert Reply:

Hi Steve! The Timbren Rear Suspension Enhancement System, part # TGMRG25C, is a good option to help reduce rear suspension sag when your Avalanche is carrying a heavy load. However, it won't correct the rear rake you're seeing when the plow is removed.

Since you've added a 1.5 to 2 inch lift to the front, it sounds like the difference in ride height is coming from the front modification rather than a lack of rear suspension support. Suspension enhancements help support the rear under load, but they aren't designed to lift the back of the truck when it's unloaded. The Timbren system does include spacers, but those are used to adjust the spring installation rather than serve as a rear lift kit. You may consider adding a lift in the back as well.

What do you usually haul when you’re not plowing, tools, firewood, or family gear?

expert reply by: Heather A

Steve M.

10/14/2026

THKS HEATHER, SORRY JUST A LITTLE MORE CLARITY PLEASE, 1) AGREED IT IS MY UNDERSTANDING THAT THE *TGMRG25C* WILL ADDRESS THE "POTENTIAL "REAR LOAD SAG"... 2) I WANTED CONFIRMATION THAT THE *T33AV* SPACER KIT ( BY INSTALLING BOTH THE 1'&1/2" SPACER TOGETHER TO CREATE A 1.5' REAR LIFT ON THE REAR COILS ) WILL ADDRESS THE **REAR LIFT** IM LOOKING TO RESTORE....TO MATCH EXSISTING FRONT LIFT.... RETURNING VEHICLE CLOSE TO ORIGN. FACTORY RAKE... SO, FINAL ANSWER....AM I CORRECT THAT I CAN USE THE TWO KITS TOGETHER?..... RESOLVING BOTH THE RAKE AND POTENTIAL LOAD SAG? PS: FYI FORGOT TO MENTION I USED CAPS FOR FOR MY VISION NEEDS

Heather A.

10/16/2026

@SteveM Hi Steve, no adding the spacers will not give you the lift you are looking for. You will need to go to a shop and get a proper lift to match the front. It will help with the sag a bit but it will not lift your truck.