Steering wheel shakes when braking at highway speeds

[KDK241]

Hello, I have been lurking on here for a few years now and have fixed many things on my trucks thanks to this forum but this time I need help.

I have a 2000 Mercury Mountaineer 5.0 AWD with 109,000 miles that was very well taken care of by the previous owners. I have owned it since 101,000 miles and this started a few days after I bought it.

The problem I'm having started with pulsating brakes at slower speeds and steering wheel shake when braking at highway speeds that seems to be coming from the front driver's side. I immediately changed the front brakes and rotors but the problem continued. I have replaced the front wheel hubs and when I got an oil change they found my inner tie rod was loose on the driver side so I just changed the inner and outers on both sides today along with the sway bar links.

The pulsating at slower speeds has lessened, it is a very light pulsation only if I'm going 40 mph or higher, and then only if I hit the brakes semi-hard, but it still shakes badly when braking at highway speeds. The calipers seem to be working properly and I got new tires put on yesterday.

The ball joints seem fine, no play in the wheel when jacked up but I have 2 upper control arms from my Explorer that are only 2 months old so I plan on changing those this weekend before I get an alignment done.

Sorry for the long first post but I'm not sure what else there is to check and TIA! - Katie

 

[massacre]

In my experience, yours might be different.

Pulsing brake pedal is usually rotors, shaking steering wheel is usually suspension or steering parts. Sounds like you have checked the suspension stuff, how about tierods, center link, idler arm etc?

 

[Spudhut]

^^^^^^ - What he said.

Pull rotors and have them turned. Might as well replace the pads too.

Re-check balance on wheels.

Check Tie Rods/Ball Joints - quick way is to jack the front up and grab the tire at the 12/6 o'clock position and see if you have movement or clicking (bad ball joints)...do the same at the 3/9 o'clock position and see if you have movement (bad tie rods).

 

[koda2000]

Your front brake rotors are most likely warped (and/or possibly your caliper slide pins are stuck). Either will cause shaking while braking, which would feel particularly bad when braking from high speed. Replace your rotors and replace or clean and lube your caliper slide pins. I would not waste your time having your rotors turned. They're probably too thin or now have exceeded the max run-out to have them turned.

While your at it, flush your brake fluid. This should be done every two years.

 

[RandomNerd2000]

Replace the rotors, they aren't worth getting turned when new ones are just a few bucks more. Also check for sticking calipers and slide pins. I'd put money on bad calipers or stuck slides.

 

[KDK241]

I took the front tires off last night and there was grease from the tie rod boot on my rotor and also a lot of grease had been pushed out from the top of the boot. (Pretty sure I put too much in). It almost looked like the tie rod end was pressed up against the dust shield so I pried the dust shield away a little, replaced the rotors on both sides with new ones and greased all the caliper pins.

Now there is only a very light vibration in the steering wheel when braking but the brake pedal pulsates strongly under normal braking. If I brake semi-hard it doesn't pulsate at all. I'm starting to think its the caliper and plan on replacing it today along with changing my brake fluid.

Also, when I have it in park or hold the brakes and turn the wheel the front end makes a lot of creaking noises on both sides that it didn't make before. Could this be the new sway bar links? It doesn't make any noise when driving and turning, only when stationary and its much louder when my foot is on the brake.

 

[koda2000]

I have 3 questions:

1) Did you clean the new rotors after you installed them? They have a protective coating on them to prevent them from rusting during shipping and storage. If you don't clean this coating off it will foul your brake pads.

2) Did you install new brake pads with your new rotors? You should have.

3) Did you break in your new rotors and pads?