Rear or under seat vibration

2013 FORD F-150

67,500 MILES • 3.5L • V6 • 4WD • AUTOMATIC

STEVE.R.BELL

MEMBER
1 POST

Having a vibration issue that occurs at 50 mph and over. It feels like a rear tire out of balance as there is no vibration in the steering wheel. The tires and wheels are new and have been re-balanced to make sure the tires and wheels are not the problem. Also, the original wheels and new tires were balanced and still vibration in the seat. I watched the "slip Yoke" service video on YouTube and wondered why this is necessary and if that might fix my issue. Also after Googling my issue I found videos of drive shaft run out.

Feb 27, 2020 at 10:44 PM

ASEMASTER6371

✓Experienced Mechanic
52,796 POSTS

Good morning,

I suspect a bad universal joint for an issue like this.

Look for any rust at the cups on the driveshaft. That is an indication of a failed joint.

I would remove the driveshaft to inspect the joints to see if they move freely.

Roy

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Feb 27, 2020 at 10:57 PM

SCGRANTURISMO

✓Experienced Mechanic
4,897 POSTS

Hello,

This could be a problem with your vehicle's U joints going bad. When they start to fail they will cause your drive-line to wobble and will cause a vibration issue. Here is a link to a guide below explaining what happens when U joints fail and what to look for:

https://www.2carpros.com/articles/how-u-joints-work

Please go through this guide and get back to us with what you find out. We can go from there if needed.

Thanks,
Alex
2CarPros

Feb 27, 2020 at 10:58 PM

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