2007 Mercury Mountaineer

Tires and Wheels problem
2007 Mercury Mountaineer V8 All Wheel Drive Automatic 37000 miles

ONLY above 65 mph, there is a constant low-grade vibration, like a 'buzz' you can hear and slightly feel. Put new Michelein tires on 4-months ago. Even had them re-balanced and rotated, but vibe still there. NO vibration in steering wheel. No 'cupping' sounds from tires.
all is tight underneath. No hint, very smooth, under 65 mph. You can take out of gear at 70 and it's still there. Does not increase in sound/feel the faster you go, ideas?
Jeff morehart
January 14, 2010.

If it is slight, it may be hard to find, but if you are like me, it will drive you crazy.

To start, if the tires are good and properly balanced, check universal joints for any play and CV joints.

Let me know what you find.


Had service done to car today and asked mechanic to check all underneath. Everything appears tight(universals, cvs, wheel bearings).
However, mechanic says the new tires, which are big 18" michileins, have a multi-purpose tread. Could this be source?
If they are, why no hint of sound, vibe at any lower speeds? Somewhat frustrating.

Jeff Morehart

Jeff morehart
Jan 15, 2010.
It could be the tires. The more agressive the tread, the more noise they will make. If he checked everything then you can at least feel safe. Keep an eye on how the tires are wearing. Make sure they stay smooth. When you eventually have them rotated, see if there is a change where the sound is coming from.

Let me know.


Hi Joe, sorry for the delay in getting back to you. Joe, could the tire inflation and nitrogen have anything to do with this buzz/rumble? All 4 new tires were filled with 28 lbs psi when installed.I'm assuming the installers new what they were doing. Normally, do these tires take more fill?
Hopefully, this will be last time I bother you on this.

Jeff Morehart

Jeff morehart
Jan 19, 2010.
Jeff: First, it's not a bother. You can get in touch with me as often as needed.

Second, 28 PSI is a little low. It could cause the outsides of the tires to wear early. You can check what the manufacturer recommends. It will be either in the owner's manual or the inside of the driver's door.

Where I work, with heavier vehicles like this, we usually recommend between 32 and 35 PSI.

Let me know if you have other questions.