Steering wheel constantly shifting center?

You have two different problems going on there. Your PS system either needs to be bled or your pump is failing.

Your rack has poly bushings? If so you need to make sure those rack bolts are good and tight in order to ensure that it will not shift laterally under the intense forces that they see while turning the wheels.

Also make sure your tie rod jam nuts are tight as well.

 

Hoe can you tell the pump is failing based off of the wheel shifting?

 

I recently had an issue on mine where I'd be driving and the wheel would be a few degrees off, hit the brakes and it went straight. I looked underneath and the steering rack piston on one side was off center a little...so my rack is bad. the truck has been sitting until a new one comes in then it will be towed to mechanic. it's very dangerous if that part fails.

 

The whirring noise that you are complaining about. Either you have air in the system which has not been bled, or the pump itself is failing. If it's not that you have a damaged line with a failing internal check valve, all bets are off considering the fact that the vehicle got hit.

 

The whiring sound is speed and drive related. Not steering. However, the truck has now developed a new issue. It now violently shakes while in 4 hi and turning.

 

With poly bushings even if you torque down the rack bolts to specs the rack will still shift causing steering to go offcenter. See video https://youtube.com/shorts/cVDlhLhoYoE?feature=share

The fix for me is welding tabs to the frame to keep the rack centered when turning.

 

So I did away with the Poly bushings and bought a new rack with OEM bushings. Truck still shifts from left to right, whirs while driving, and now judders in 4hi.

 

Are you referring to the rack still shifting left to right or the whole truck wanders?

 

Rack is now solid. Steering wheel still shifts left to right.

 

If it's shaking while in 4 wheel and turning then it sounds like you have a front differential issue with the gears inside being the culprit of your shaking or juddering while turning.

If your steering wheel is shifting constantly and the rack bushings are now stock again then you need to methodically go up and down your steering wheel and inspect the connection points. It almost sounds like you may have worn out splines either at the rack or at the intermediate shaft which connects to the steering rack. If not there then maybe further up. Accident vehicles are always a bitch to deal with for the exact same reasons which you are having. Some never turn out quite right no matter how many parts you throw at it.

 

Steering rack is brand new. Just ordered new upper and lower intermediate shafts. Diff was regeared pre accident. It is possible however that the front diff has internal damage due to the accident because my driver side CV axle snapped before the accident.

 

That's precisely what I'm thinking. Diff got banged up internally because if you hit something hard enough to snap a CV then you know some of that transferred into the diff.

 

Indeed. Still don't know what would cause the wheel to shift back and forth while steering but that could very well be the culprit of the other issues.

 

Replace those intermediate shafts and recheck it from there. Something with splines is bound to be chewed up.

 

The rack mounting bolts have a shank diameter that is smaller than the threads so the bushings aren’t tight to the shank. Poly bushings really bring that issue out. You could ream the bushings and the frame for a 1/2” grade 8 bolt. Beats welding tabs on the frame that’ll make the next replacement a nightmare

 

I will keep you guys informed. I hope something comes of it. Its the only steering component save the power steering pump that has not been replaced.

 

Did you ever figure out what was causing this?