[Karenp76]

Morning All.
I have a new to me 2012 Acadia Denali that I bought used and picked up June 1, 2020.
I drove it home.. around 80km the steering wheel started to shake...nothing else just the steering wheel...fig it could be tires as they were in not too good shape. put brand new tires on it...still shakes...brought it to deal as have 90 day warranty and they could not fig it out (said was balance and they balanced it (we brought it back to our tire guy and dealers balance was 3.5 inchs off)).
Brought it to our mech and they cant fig out. i am going to be bringing it back to dealer until the fig it out... unfor i have not even had the car a week to myself yet

and have spent over 1000 trying to fig this out...
-Wheels and rims been road force checked
-swapped tires
-front end inspected
-alignment done 2 times
has anyone else had a shaking steering wheel...seem to be high speed (hwy) random (70-90km)

 

[speleos]

Welcome to the forum.
Could be something worn in the steering gear or suspension. Might even be the road surface itself if it happens on one particular stretch of highway

 

[divotdug]

Had this on a previous vehicle due to a slightly out of round wheel. No amount of balancing was going to correct the issue.

 

[MI-Acadia]

Had a similar issue with a Jeep many years ago - turned out to be a bad steering damper (small shock absorber type device incorporated into the steering linkage). Don't know if the Acadia has a something comparable.

 

[Nghtrdr]

This is going to be a long post!

Btw I'm the hubby!

Just an fyi for those with the same issue. Here is what was found and fixed by myself after several trips to GM and my own mechanic (4 techs looked at it and scratched their heads).
As stated by Karen the steering wheel would shake at 70+ km speeds. This shaking was not felt anywhere but in the steering wheel.

What was done with no fix:
New shoes (Michelin)
Alignment done twice. Once by GM and once by my mechanic
Tire balanced 3 times
Tires and rims road force check separately and then road force balanced (no faults found)
- Road force check and balanced by GM as well even though we told them it was just done.
Both front bearing assemblies done by GM (now they are just throwing parts at it)
Front rotors run out checked on vehicle and rotors cut as precautionary measure.
Front rotors cut again by GM

At this point GM gave us the vehicle back stating it was not fixed but was much better and as far as they were concerned the issue is fixed.

I decided that this needed to be fixed 100% and there could only be a few things left that it could be. Driveline, brakes and wheels. The wheels were checked several times already and I was sure they were not the issue. So I started with the cheaper stuff first. I placed an order with rockauto for new AC Delco front brakes. While doing the brakes I noticed the brake fluid was extremely dark. If you don't know brake fluid is hydrascopic (absorbs moisture from the air). The fluid looked and smelled as though it was original (10yrs old). The moisture in the fluid can boil and steam inside the brake lines causing all kinds of issues. This needs to go. Unfortunately while attempting to open one of the front bleeder it snapped off. Now I've been down this road before and let me tell you. If you've ever tried to remove a broken, rusted, siezed bleeder before you know it never works out. So another order for an AC Delco brake caliper. I did bleed the other 3 bleeders and thorough flushed the reservoir

The new brakes and partially flushed braking system made a huge difference in the shaking. For the most part is was gone. The wife did report it had returned while on the highway again.

I replaced the caliper and finished flushing the brakes.

Weeks later now and the issue has not returned. So 100% fixed finally!

It's my believe that the return of the shaking after the brake job was because of old moisture laden fluid stuck in the caliper. This fluid would heat up and boil/steam inside the caliper causing the caliper to actually move in and out rapidly. The old rotors and pads could be of any manufacturer. They were probably the cheapest the previous owner could find knowing they were selling the vehicle anyways. Now i dont know about you but i would never skimp on brakes even if i was selling. I wouldn't be able to sleep at night!

In conclusion,
The fix was fluid flush and new front brakes. At the very least I got two new front bearings out of GM for free. In the end this issue cost me a total of around $1600 and a loss of use of about 4 weeks to diagnose and fix not including the tires. The tires were already on the to do list at purchase of the vehicle. I do plan to replace the rear brakes next spring.

Thanks for reading

 

[speleos]

Thanks for the update. Definitely a point to ponder for anyone faced with a similar situation.

 

[JayTee2019]

Btw I'm the hubby!
Weeks later now and the issue has not returned. So 100% fixed finally!
In conclusion,
The fix was fluid flush and new front brakes. At the very least I got two new front bearings out of GM for free. In the end this issue cost me a total of around $1600 and a loss of use of about 4 weeks to diagnose and fix not including the tires. The tires were already on the to do list at purchase of the vehicle. I do plan to replace the rear brakes next spring.

Thanks for reading

Wow. . . what a venture. Not even the experts suspected old brake fluid might have caused it. But, yes, I always have the brake fluid flushed and new fluid every 4 years usually. Not worth the other issues it can cause as well . Many just keep driving a vehicle till it breaks.
As you say, new tires were due and GM paid for the two new hubs.
Hope to see more of you on the forum. Another member is always appreciated.
Good job !

 

[Nghtrdr]

Wow. . . what a venture. Not even the experts suspected old brake fluid might have caused it. But, yes, I always have the brake fluid flushed and new fluid every 4 years usually. Not worth the other issues it can cause as well . Many just keep driving a vehicle till it breaks.
As you say, new tires were due and GM paid for the two new hubs.
Hope to see more of you on the forum. Another member is always appreciated.
Good job !

Thanks for the warm welcome JayTee.
I'm a bit of a lurker but will speak up if/when it's needed.

I didn't know the wife had posted this here to be honest. Once I saw the post I figured I could save someone the grieve we went through. I'm no mechanic but have been wrenching for many, many years and I've never seen or heard of brake fluid behaving in this manner.
Sometimes it's the simple things that are overlooked we should really pay attention to!

Thanks again