Hi all. My 2018 XLT 2wd SC has a high frequency vibration i can feel especially at highway speeds. almost like road or tire noise. The tires I replaced already, and it doesn't feel or sound like differential or wheel bearing to me. There's 65K gently used miles on the truck. does anyone here have any experiance with the drive shaft on these trucks. Im reading about the splines needing greasing every so often between the two pieces?

 

A friend of mine actually had to have his drive shaft balanced to get rid of his vibration similar to what you describe. Not sure if that's the case here or not though.

 

Can you relate this new vibration to anything? I mean a weight could have come off driveshaft, you might go under and investigate, if it was recently, you might still see a clean mark where previous weights were? I wouldn't rule out tire balance either, weights come off, I once got new tires and turns out some were bad, took them 9 tires to get me 4 good Firestones. (needless to say, I'll never buy another)

 

It sounds to me like a wheel bearing noise--damn hard to pin down the location. I had a high frequency whir/hum that was speed dependent--became noticeable at +/- 30 MPH and more so at xway speed--and could feel it very lightly in the steering wheel.
Ended up replacing both hubs and the noise was gone. Happened at just over 40K miles...2018 lightly used truck.

 

I have a similar vibration, 2018 xlt, 4x4, max tow, 3.5 eb, crew cab, short box. Dealer replaced the driveshaft which made no difference. Second dealer tried tires, wheel bearing, rear brakes, ring and pinion, then gave up. They were unable to determine the source with their vibration analyzer. It acts like bad u-joints, worse under load, coasting down a hill it nearly goes away.. My next step is a driveline shop to get the shaft balanced and check the u joints and check to see if it may be twisted.. Other thought is that it may be a harmonic resonance It starts around 25 mph and is worse at 50 mph and not noticeable at 70 mph. The large weight attached to the transmission is probably there to cure a similar vibration. So maybe add weight to the driveshaft? Or try a steel equivalent?. Currently at 89k and been shaking since new, gradually getting worse.