New Member
Jan 23, 2011
Lafayette, LA
This thread will have information useful for lifting and leveling your 99-present GM IFS (Independent Front Suspension) truck. For now I'll stick to basics and will do more hardcore offroad info upon request. I AM NOT RESPONSIBLE FOR ANYTHING YOU ATTEMPT TO INSTALL ON YOUR TRUCK AND SCREW UP.

First off- All trucks can be body lifted.

Second- Whenever lifting or leveling your IFS truck, always check your front end angles after any adjustment to the suspension to make sure your front end components are at a safe angle and not in a bind. This is to ensure your safety and longevity of your front end parts

Third- Always make provisions to get an alignment after any suspension work is done.

Proper Gearing for Common Tire Sizes- Applicable for 10 Bolt and 14 Bolt Rear Ends/ 8.25" and 9.25" Front Chunks
3:23/3:42/3:73/4:10-- 31"-32" tall
4:30-- 33"-34"
4:56-- 35"-36"
4:88-- 37"-38"
5:13-- 39"-40"
5:38-- 41"+

-Detroit Locker and limited slips from Eaton/Detroit are available for 10 bolt rears. Only replacement open carriers are available for 8.25" front chunks because they are not strong enough to hold limited slip/locking carriers.

Rear Lift- All Models and Years

Blocks and Zero Rates
-Should NEVER be stacked
-this is the cheapest method of rear lift and blocks are made in a wide range of sizes
-the larger the block, the more axle wrap (wheel hop) the truck will have
-Zero rates can be used in conjunction with add-a-leafs or shackle flips to compensate for any rearward movement of the rear axle.

-this is an extra leaf that is added to the leaf spring packs on the rear of the truck
-Length of the spring determines how much lift will be gained
-usually settles roughly an inch after some use
-very cost effective
-stiffens the ride of the truck

Shackle Flip
-provides new bracketry that scraps the stock tension shackle design in favor of vertically hung shackles
-offers more offroad flex and maintains stock ride quality
-most labor intensive of any rear lift method
-good for achieving lift higher than 6" as it is compatible with longer shackles, add-a-leafs, lift springs, and blocks

Lift Leaf Springs
-spring packs that have more arch than stock and are made in a broad range of lengths and lift heights for different applications
-highly increases the stiffness of the truck's rear suspension

Leveling and Lifting a 99-07

Leveling these trucks is done in different ways depending on what suspension setup your truck was equipped with from the factory.First we'll deal with a standard 2WD setup.
Most 2WD trucks were built with a coil sprung IFS suspension. These can be leveled using a combination of parts, or individual parts depending on desired lift height, such as spindles (also called knuckles), coil spring spacers, or lift coils.
4WDs, all HDs, and torsion bar suspended 2WD 1500's have only one way to level, which is by cranking the torsion bars and/or using leveling keys. Simply put, the torsion bar acts in place of a spring pack or coil spring in the suspension, and the adjuster keys either add or remove load on the bar by "twisting" it to either increase tension or decrease tension, and thereby lifting or lowering the truck, respectively. The keys themselves are indexed (the position the hex hole is bored into the key) for a certain amount of adjustment. Leveling keys have a higher adjustment index, meaning more lift can be gained.

-Ford keys or generic aftermaket leveling keys will lift a 1500
-Stock 1500 keys or generic aftermarket keys will lift an HD
-Stock HD keys will lower a 1500
-HD torsion bars on a 1500 will stiffen the front suspension and hold lift for longer

Installing a lift kit on a coil sprung 2WD is the least complicated task to perform, and usually uses a combination of spindles, lift springs, and always contains lower control arm drop brackets on larger lifts to maintain safe front end angles.
Lifting torsion bar IFS is much more difficult and expensive due to there being a torsion bar drop bracket, differential drop bracket, and CV (constant velocity) joint spacers depending upon the type of lift ( in this case knuckle).

Knuckle Lifts
-Uses a combination of a small amount of differential drop and taller knuckles to gain lift, this also means that there will be little to no room to crank up the front because the CV's and steering components are already at an angle without being crancked
-cheaper than full drop
-increases the track width of the front of the truck

Full Drop Lifts
-Drops the front chunk the full amount of desired lift height, meaning these kits are more flexible and allow for more crank
-does not increase the front track width of the truck
-usually quite expensive

Leveling and Lifting 07-present 1500 2/4WD
This Era of truck (GMT900) uses a coilover/strut IFS design and is much easier to lift and level than the GMT800s (99-07). Leveling for 2/4WD is performed by placing small spacers on either the top or bottom end of the strut. It is NEVER a good idea to "stack" spacers on both ends of the strut for safety and longevity concerns.
Lift kits for GMT900 2/4WD trucks uses much less bracketry and is easier to install than GMT800s. There still is however an obvious difference bewteen the 2 and 4WD kits.
Last edited:


le skinneh mod
Jan 24, 2011
Elk Grove, CA


New Member
Jan 9, 2011
Use the info as you want. The ratios I put in are for near-stock mechanical advantage.

I'll edit that in.

Its not really stock mechanical advantage. Stock rpm at speed, yes. But if you go from 2.65s and 3.73s to 4.56s and 35s its not going to have as much power.