Trouble shooting - front end shake

[redbird2]

Have you recheck the idler assmebly if it would be loose it could be causing that . Does it make a differance with or with brake apllication possible wraped rotor when the brakes released less noticable with slight or low brake application you feel it.
good luck

[DA BIG ONE]

I would check the front dualie wheel adapters for trueness, then check hub/bearing assemblies.

Not having a dualie I do have a 2500 4x4 and have changed out frt hub/bearings well before 100k

[rtphillips370]

The shake feels if it is dampened when applying the brake, I have not had the ball joints, pitman or idler arm changed and last check a year ago from the local heavy vehicle mechanic who checked it and the alignment states they appeared to be fine back then, I also am running class "D" tires...

[rtphillips370]

Well I am still trying to figure out this mystery, to date since starting this thread, I have replaced the steering gear box, idler arm and all of the front bearings. I have also had all 7 rims and tires checked for balance, trueness and rotation and they all pass. The rotors I purchased new approx four years ago. The idler arm I just replaced this past week and since then the shake is 80% gone compared to before replacement.

BEFORE replacement, the shake was intermittent between 30-45 MPH didn't matter if i was accelerating, slowing or cruising, nor did it matter if I applied the brakes, lastly, the shake was more prevalent at times during turns (S-curves) at these speeds or when towing my RV. Moreover, the shake could be felt throughout the truck and not just in the steering wheel.

Now SINCE the replacement of the bearings and idler arm, the shake is very minor and only in the vicinity of 40 MPH, and slightly more prevalent during deceleration / braking, and at times, during turns (S-curves) at 40 MPH.

Now when pulling the RV, both before and after the replacement of the idler arm / bearings... During accelerating up from stop through the 40 MPH range, the shake at times (intermittently), will get so bad that the whole truck shakes so badly (including the steering wheel) that I have no choice but to stop the truck quickly to maintain control. This has never happened at speed or on deceleration / braking with the RV because when this occurs at this severity, i cannot get through 40MPH. although stopping and then starting again, will diminish the shake but not alleviate it...

The truck has 150,000 Miles on it, and i am considering having the upper/lower ball joints replaced, tie rods and possibly the center link, even though the local shop doesn't find anything wrong with them, I am also entertaining purchasing an after market steering stabilizer shock absorber from JC Whitney (I don't know if it will help) like those seen on most 4X4's.

I have had one mechanic advise me that if the hydro booster / power steering pump go bad (weak pressure from the PS pump)... will let the steering gear box get sloppy. And he advised to replace the power steering pump and get rid of the hydro boost and add a large vacuum pump and a vacuum assist to my brakes in lieu of the hydro boost assist it has now.

Either way, I am looking in the neighborhood of $500 or so, maybe more to rebuild the front end steering components or go with a rather drastic departure from original equipment on a 'maybe' something that I am not comfortable with.

Anyone have any ideas or suggestions on how to solve this puzzle? its driving me nuts and possibly broke

[redbird2]

it this shake only in the streeing wheel have you checked the driveline it has a 2 piece driveline is the carrier bearing good if it is loose it will cause a speed vibration also check all the u joints as most of those trucks have no greaseable joints maybe one is stiff causing the drive line to vibrate and when you brake it then not under a load so it doesn't vibrate as much, easy to check won't cost you anything to drop shaft and check just a little time

the idea of replaceing the hydro boost with vacuum set up not wise idea IMO that just added more things to break on the truck you can not buy at any local parts place or dealer

just an idea
good luck

[rtphillips370]

it this shake only in the steering wheel

Its mostly in the steering wheel but the more violent the shake becomes more it is fel throughout the front of the truck...

[cshade]

i have the same exact problem on my 94 suburban 2500 4x4. I replaced the shocks, steering stabilizer, and greased the drivetrain, ball joints, and tie rods and the effect was minimized but still there. Interesting that you mentioned the power steering pump, because mine is going out. Will update when I replace it. By the way remanufactured ps pumps are like 100-150 at stores and online...40 without the resovoir, but you have to press it back in yourself.


let us know your progress!

--Charles