Speed sensitive clunk

[Squishy]

I've been getting a speed-sensitive clunk lately in the front end of my Escape, which I think is one of the CV joints going bad. Just wanted to get a second opinion on the noise.

The frequency varies with speed, and happens only when coasting. It disappears when I apply gas or brakes. It sounds like the tire running over a single rumble strip at a time, roughly in time with the rotation of the tire (if you've ever run across one of those rubber speed sensor wires, that's what it sounds like). I can feel the clunk in my steering wheel, and it doesn't matter whether I'm turning or going straight. Sometimes when I'm coasting at a very slow speed, the clunk will show up but will be slightly prolonged, as if it is caused by rubbing metal.

Also, today I drove above the speed limit on the highway, and noticed a bad vibration from the wheels. At first I thought it was dirt and rocks stuck to the inside of the rim, but then I noticed that the vibration tended to go away for a few seconds, only to return without me varying my speed at all. The vibration showed up above 120 km/h, and was still present at 155 km/h.

 

[cousincletus]

Bad wheel bearing? They can make all kinds of funny noises when going bad. Jack up the car and see if you have any play in the bearing. Also, while you're under there, check your CV boot, although I doubt that's your problem.

 

[Squishy]

I had considered that, but to have it actually make a "clunk" noise, wouldn't that be bad enough to show up whether I'm braking, accelerating, or coasting? As it is, it only shows up while coasting.

I'm driving over to where I have my 22" floor jack, so I'm going to do a thorough inspection there.

(BTW, the main reason I'm suspecting CV joints, other than the specific symptoms, is that I recently drove/fell into a deep pothole on a dirt road that ate my tire up to the hub. Dirt and rocks may have torn the CV boot, but I didn't have a jack or lift where I live right now, so I just hoped for the best. I was going slow enough that I should have avoided bearing damage in that incident, and I didn't know whether it would act as a red herring if I included that information.)

 

[wander2039]

How many miles does your Escape have? The front ends on Escapes are hard to diagnose. We have three of them at work at all have had the clunk at one period of time. Each time it's a a different part - sway bar links, cv joints, ball joints, tie rods. Sway bar links are a common source of clunks on Escapes though. Do the pull test side to side top and bottom first and i'd replace the end links if there's no play in the tie rods/ball joints.

 

[mechtech2]

Brake rotor.
Wheel bearing.
Possible C/V or support bearing for axle [symptoms aren't always classic]
Final drive in transmission.

 

[moribundman]

I'd also make sure that the none of the brake pads is loose. I've seen that happen.