'13 GX460 - Tire/Brake vibrations after new tires and brakes!

[jb325is]

Obviously, title is in jest.. But I've been fighting some vibration issues on our '13 GX460 for quite some time. Looking for some input from those who have been through this and had some success getting to the bottom of it.

2013 GX Premium
- 160k miles (Lots of HWY- we road trip a LOT)
- 275/65/18 Cooper Discoverer AT3S (30k miles) --> 275/65/18 Michelin LTX Defender M/S² (NEW as of today)
- New brakes (EBC Green stuff pads and Rotors)

Symptoms:
- High speed vibrations, most noticeable on interstate between 60mph and 80mph. Sometimes severe, sometimes not but always noticeable
- Brake pulsation. Can feel it from high speeds and pedal pulsation when coming to stop. Feels like the rear most of the time, but can feel it in the wheel when going to the brakes from interstate speeds

Next Steps:
- Brake drum adjustment- When I did the brakes initially, I had to go back the following week and replace the brake drum hardware because I broke one of the spring retainers. This *probably* caused a e-brake drag that heated up the brakes more than normal, maybe resulted in some pad deposits from the elevated heat
- I bought a rotor hone from Summit and will be pulling the rotors and cleaning deposits off of them this week. Maybe something went wrong on the bedding procedure and/or the e-brake drag mentioned above
- Check brakes after hwy driving to monitor temps, possibly detect caliper dragging (I've heard that's an issue). I have access to FLIR camera as well if need to get really fancy

Looking for input really and just guidance on a diag procedure from those who have done it. Not looking to throw money at it but I am a capable DIY owner, just don't have much experience with these. I'm a lifetime BMW, Land rover and motorsports guy... I only bought this thing because I didn't want to have to work on it!

 

[ericm979]

Did the non braking vibration change with the new tires? If not then tire+wheel balance isn't the problem.

I'd check that the rotors are really fully seated against the hub. If there was a piece of something in there the rotor would act like it was warped, and it would probably cause a dynamic imbalance as well.

I recently changed my rotors and brake pads (using stock parts) and got rid of a front wheel brake shudder that was getting annoying. Even though the parts I took out were not that worn, the new ones with properly bedded pads work noticeably better.

 

[jb325is]

Did the non braking vibration change with the new tires? If not then tire+wheel balance isn't the problem.

I'd check that the rotors are really fully seated against the hub. If there was a piece of something in there the rotor would act like it was warped, and it would probably cause a dynamic imbalance as well.

I recently changed my rotors and brake pads (using stock parts) and got rid of a front wheel brake shudder that was getting annoying. Even though the parts I took out were not that worn, the new ones with properly bedded pads work noticeably better.

It improved, but did not go away. The Coopers were noticeably cupped

I'll check on the rotor / hub faces tomorrow.

I'm wondering if I should have used stock parts now, some other stuff I read suggested these trucks were under-braked and that pads with uprated heat tolerance would be a gain.

 

[r2m]

To address the high speed vibrations, find a Yelp 5 star rated, with a LOT of reviews, shop that specializes in front ends. You may have some worn out bushings.
Also you may have thrown a wheel weight, so have your wheels balanced again, or easier still, rotate them and see if putting the rear wheels up front help.

 

[GrizzlyClint]

I'm wondering if I should have used stock parts now, some other stuff I read suggested these trucks were under-braked and that pads with uprated heat tolerance would be a gain.

Upgraded rotors and pads really help these rigs brake well. My PowerStop heavy duty brake kit is amazing.

 

[WoodstockGXer]

Vibrations at highway speeds are most likely tire or wheel related, either out of balance or out of round or both. A bad drive shaft can do it too, but it is much less likely. Just my 2 cents.

 

[HVLA]

I am assuming you used all new hardware and cleaned and greased everything and dont have a sticky caliper?

 

[jb325is]

Busy couple of weeks but I'm getting back to this thing now. No real improvement, my stready-state HWY vibration is noticeable but not severe since I switched from the Coopers to the Michelins. My brake pulsation is just as bad as ever, big vibrations when going to the brakes on the HWY and severe pulsation at low speeds, you can feel the brakes grabbing/releasing when coming to a stop. While doing an oil change today, I did take a closer look at the brakes and front suspension and think I have a path forward, but would love to hear some more feedback from others.

Brakes:

• Some interesting deposits here, more on the front than rear. The pads / rotors have <5k miles on them, they were EBC Greenstuff pads with the EBC rotors. I think the deposits could be contributing to or causing my pulsation issues. The EBC pads supposedly don't require bedding because they have a friction coating of some sort, I'm wondering if something went wrong there and that coating is cooked onto my rotors, causing the big pulsation
• I haven't had a chance to put a infrared thermometer on the brakes, but don't have any real reason to think I'm having a caliper drag issue- I can get 18.5 mpg on the hwy, which seems to be pretty good from my experience. I'm not opposed to changing calipers, but I need to see some indication of drag before throwing parts at it.
• Next steps on the brakes will be: Machine the rotors and replace the pads with something more conventional. I still think these are under-braked (and under-powered, and under-engineered, and economically coated) and I'm not convinced that stock pads are the right call for the long run, because I do think they are at risk of being overheated easily. Anyone have any input on replacement pads for these rotors once I machine them?

Suspension:

• Can't feel any suspension play @ 12/6 or 9/3
• I do have a slight clunk when turning into parking lots or driveways, in addition to the vibration @ speed
• LCA bushings have some visible cracks, ball joint boots all look pretty old and cracked. All bushings look pretty similar to the picture
• Next Steps on the suspension will be: Upper/Lower control arm replacement, inner and outer tie rod replacement. Not going to do hubs unless something feels really rough or scratchy when I pull it apart. Hubs and steering rack bushings are on the radar but not going to spring for that until I replace the previously mentioned items. Anything else I should replace while I'm in there doing the arms and TRE's?

Also sanded the headlights with 1000/2000 and buffed them out with Meguiars 105/205 and changed the oil using Valvoline Synthetic 0W-20. Mileage is just over 161K

 

[ericm979]

I replaced my pulsing brakes with stock rotors and pads. The parts on there were 1/4 worn stock parts. I carefully bedded the pads in, taking care to not stop with the brakes on while the rotors were hot. Bedding in made a noticeable difference. While the brakes are not as good as the brakes on my Golf R, they're not bad for a truck. I live on a steep twisty road and the brakes do fine on it.

 

[jb325is]

I ended up putting new OE rotors and OE Akebono pads on the GX and it fixed the pulsation. I think the ceramic pads were the issue, leaving an uneven film on the rotors. Listing this thing for sale now that it's vibration free!