Vibration that starts at around 55 mph

jmd349

Member
Joined
Jan 1, 2020
Messages
35
Location
Starkville, MS
In the last couple of weeks I have noticed a vibration that starts when I reach 55mph and upward. The faster I go above 55mph the vibration doesn’t seem to get worse, but just maintains. I can feel the vibration in the steering wheel and I can notice the hood shimmy up and down as far as the hood latches allow. Even notice the passenger side seat shake more irregularly. I can hold a steady line down the road still With the steering wheel.

Bit of background. I had brand new 31” BFG KO2’s mounted last spring and have put roughly 2000 miles on them since with no problems. I did have them rotated mid-December but have driven the Jeep in excess of 55mph a few times since then with no problems. My Jeep is a 95% pavement runner and I probably am actually in excess of 55mph only 25% of the time I drive it (weekend, errand runner ride).

This may have not a thing to do with it, but just recently before I noticed the vibration I drove roughly 10 miles of gravel /bumpy road. At one point during this ride I was traveling about 20mph (only in 2nd gear) and I was going down hill on a fairly sharp turn and the loose gravel got me a little squirrely side ways, but I straightened it up and moved on no problems. Ironically, the first time I got above 55mph since then is when I noticed the vibration.

Anyway, this is what I have to share. If you guys have any feedback that’s great. Work, wife, and kiddo keep me busy so I’m just going to take it to the shop in the near future. If I come up with a for sure root cause, will be sure to report back.
 
Maybe lost a wheel weight on the bumpy road. Do you have free lifetime balancing from your tire installer? That would be my first move.

You might even be able to see where one of the weights came off from a dirty (or clean) outline but maybe not if it’s been a couple weeks. Likely one of the front tires.
 
Maybe lost a wheel weight on the bumpy road.
Good thought process.

You post indicates there was a change. I'd look for a missing weight.

I'd also check for a loose tire and good lug purchase if you have aftermarket wheels.

Also,it's possible to lose a drive shaft weight.

I'd also check for a rock slung into a place it shouldnt be as well ....rare but possible

Check the tires for damage ...and you may want to rotate them to see if it changes anything...even a broke belt is possible when you got squirrelly. It may take substituting them one at a time to eliminate the tires.
 
A slight bend to the tierod when you were shucking around that curve? Or draglink, tho less likely. Most high speed vibes come from tire/rim problem. This starting after a known event should help you nail it down. At the far less likely end of the spectrum is a wheel bearing that was on its last leg, but I would suspect getting tires rebalanced should cure it. Try rotating front tires to the back and see if that works. If you now have a smooth front, but now a vibe coming through the tub, you'll know it's a tire/rim issue. Do you have aluminum or steel rims?