SOLVED PAGE 5: Shudder/shake/vibration when hitting bumps at highway speeds

[clandr1]

Hi everyone,

I decided to place this thread here, even though I have 100% factory suspension. I've recently noticed an issue where the truck seems to develop a temporary shudder/shake after hitting a bump on the highway (going 70mph). I have owned the vehicle since new. It currently has 217,000 miles on it and has never been abused.

I'm not sure what is causing this issue, but here are the items I've replaced over the years to give you a baseline:

MOOG Tie rods, AC DELCO pitman arm: 121,000 (I have not replaced the idler arm)
Bilstein shocks: 163,000
Timken wheel bearings: 175,000 miles
AC Delco steering gear box (this was not due to a steering stability/control issue, but a power steering related issue): 199,000

Some questions floating around my head:
Could the pitman arm be causing this?
Could the tie rods already be worn enough to warrant a second replacement?
Could the front or rear control arms need replacement?

Note: I checked the ball joints and they seem to be in good shape - no movement I could detect trying to pry the tire up and down with the front end jacked up (jack was placed on the lower control arms).

Thanks for any help or ideas. I suppose I could just take it to a shop and pay them to diagnose it, but I try to keep my truck out of the shop unless I absolutely must take it in.

 

[Big Mama]

You tried moving the wheels with your hands at 6&12 how about at 9&3?

 

[mattbta]

Did you take the centerlink/relay rod off when doing any suspension work?

Also, check your jounce bumpers. They could be disintegrated. New ones need to just touch the LCA's.

 

[clandr1]

You tried moving the wheels with your hands at 6&12 how about at 9&3?

Yes.
6 & 12 had no movement which is what makes me think my ball joints are ok.
9 & 3 had some movement, but it was hard for me to tell whether it was the rubber on the tire flexing, or something else. I didn't see any movement in the tie rods when working the wheel back and forth at 9 & 3.

 

[clandr1]

Did you take the centerlink/relay rod off when doing any suspension work?

Also, check your jounce bumpers. They could be disintegrated. New ones need to just touch the LCA's.

Yes, I took off the center link when I replaced the pitman arm and tie rods a long time ago. Given this is a recent problem, I don't think it's related, but what is your train of thought on the centerlink and it's potential contribution to my issue?

Are jounce bumpers the same thing as bump stops? I'll check them tomorrow.

 

[mattbta]

Yes, I took off the center link when I replaced the pitman arm and tie rods a long time ago. Given this is a recent problem, I don't think it's related, but what is your train of thought on the centerlink and it's potential contribution to my issue?

Are jounce bumpers the same thing as bump stops? I'll check them tomorrow.

Make sure the centerlink is oriented properly. Mine and several others weren't and produced very weird steering issues because the tie-rods weren't aligned. Here's a pic, but the whole thread is worth a read: https://www.tahoeyukonforum.com/thr...g-at-near-full-lock.86256/page-2#post-1040842

Jounce bumpers/bump stops, yes, folks use those terms interchangeably. 15153958 is the GM part number. Here's mine, a Texas truck after 13 years.

 

[exp500]

In one of the newer posts another member has loose steering box mount bushings. Similar to what you are describing. Not sure of matching year though.
If you jack up front end, move tires by hand turning left/right fully and feel no binding, do it again watching components for a "shift" in relative position. Usually indicates wear that can be duplicated with a pry bar. Another help is watching while prying on tires to load/unload ball joints. Then do it again looking at rest of components. Two people a big help.

 

[clandr1]

Make sure the centerlink is oriented properly. Mine and several others weren't and produced very weird steering issues because the tie-rods weren't aligned. Here's a pic, but the whole thread is worth a read: https://www.tahoeyukonforum.com/thr...g-at-near-full-lock.86256/page-2#post-1040842

Jounce bumpers/bump stops, yes, folks use those terms interchangeably. 15153958 is the GM part number. Here's mine, a Texas truck after 13 years.View attachment 250640

Were these in the front or rear of your truck?

 

[Fless]

The fronts should be in contact:

https://www.tahoeyukonforum.com/thr...ahoe-yukon-today.12502/page-2922#post-1377412

 

[mattbta]

Were these in the front or rear of your truck?

Front. And like Fless said, should be in contact with the LCA.