Torsion Bar Adjustment

gtgmc · April 2, 2009

Can anyone help?

I have a stock 2002 gmc 1500 4x4 Z71. I want to raise the front end just to level it out, and plan on putting new tires on relitively soon. I am hoping that 285 75 16's will fill the truck out a little. I have been trying to read up on how to adjust the trosion bars, but have yet to find instructions from A-Z. I do not want to buy any leveling kits or mods just yet. I am looking to raise it as much as possible solely by adjusting the torsion bars, while keeping the truck as safe as possible. Any input would be greatly appreciated.

2000DV4.8 · April 2, 2009

To crank the torsion bars, you will need to adjust the torsion key adjustment bolt, which is located in the torsion bar cross-member. The cross-member is pretty much directly below the seam between the front and rear doors. Follow the torsion bar into the cross member, then you will see an adjustment bolt. That is the bolt you need to... well... adjust.

Ok, so now for the adjustment process. You will need a jack and jackstands, a bottle of whiteout, an 18mm socket, and preferably a 1/2" drive ratchet.

Measure the original fender height heights with the truck on flat level ground. Then jack up the front of the truck, and put the jackstands under the frame. Mark the adjustment bolt and the cross-member with whiteout so you can better keep track of how many rotations the bolt makes. Each full revolution of the bolt equals about 1/4" of height. I'd start off with 4 revs, which should net you about an inch.

Let the truck down bounce on the bumper a little bit, and drive it around the block and make a couple of hard stops to let the suspension settle. Then park the truck in the same spot as before, and re-measure.

Repeat as needed until you get to the height you want, it is completely normal for one bolt to have more thread showing, or for one bolt to take more revs to raise the truck (I had to turn my drivers side bolt 2 full revs more to get the truck to sit level).

Just keep in mind, your ride will stiffen up, and if you go over 1.5" it will REALLY start to suffer. Also, if you go much over 1.5", you will start to wear through parts like CVs, tie rod ends, ball joints, and pitman/idler arms much quicker than normal. Keep the height reasonable, and you should have no problems, but if you go over 1.5", you're risking the aforementioned parts failing prematurely.

ezskanken · April 3, 2009

Can anyone help?
I have a stock 2002 gmc 1500 4x4 Z71. I want to raise the front end just to level it out, and plan on putting new tires on relitively soon. I am hoping that 285 75 16's will fill the truck out a little. I have been trying to read up on how to adjust the trosion bars, but have yet to find instructions from A-Z. I do not want to buy any leveling kits or mods just yet. I am looking to raise it as much as possible solely by adjusting the torsion bars, while keeping the truck as safe as possible. Any input would be greatly appreciated.

Hey There GTGMC,

I got a 2002 GMC Sierra K1500 Z71 too. Stock suspension and threw some 285/75/16 on it and it looks great. The tire place had adjust the torsion bar a little because I wanted the truck to sit level like you do. When the bigger tires went on, my truck leaned in the front a bit, I'm not a big fan of that look. But just my two cents, take it ez...oh, you can check out some pics in my profile deal I think...

Alljackedup408 · April 3, 2009

also be careful when youre off road... if youre out there bangin around and all over the place.. lot easier to break stuff... under more tension

Stylous · April 17, 2009

remove the rubber snubbers to help with the ride. People never mention that but it does help the ride and keeps you from bottoming out.

Bull-Dogg · April 17, 2009

whats a rubber snubber

Stylous · April 17, 2009

whats a rubber snubber

Sorry, they refer to them as bump stops here.

2000DV4.8 · April 17, 2009

remove the rubber snubbers to help with the ride. People never mention that but it does help the ride and keeps you from bottoming out.

Those bump stops have nothing to do with the ride being harsh when the torsion bars are cranked (in fact, they have less of an effect than at stock height).

The harsh ride comes from either the shocks 'topping' out (becoming fully extended) when the truck goes over bumps, or the upper control arm hitting the droop stops with the suspension at full droop, whichever happens first.