Vibration While Accelerating

[SyndicateZ]

damn

 

[Texas]

I was going to suggest checking the rear differential and adding a bottle of Motorcraft Friction Modifier to the rear diff. I had a similar problem and was surprised that the problem was coming from the rear limited slip differential. Easy job to do yourself, but if you do, wear gloves. the stuff stinks pretty bad and does not come off of your fingers quickly. Won't tell you how I know.

Update: I mentioned your post when I took it in last Thursday (dealer still has it, haven’t heard back). Since it’s under warranty, I’ll let the experts figure this one out (and get their hands dirty).

They’re doing a diagnostic first, but the tech agreed it’s probably a rear diff issue. Also found out the transmission on my truck has been rebuilt TWICE already. Likely have had this issue for a while, and other dealers couldn’t figure out what it was.

 

[Texas]

Update: dealer informed me the u-joint is cracked and needs to be replaced. Hopefully problem solved. Part is ordered, but it’s been two weeks without my truck

 

[Texas]

Update: had to replace driveshaft and u-joint and whatever other small components. Ride quality is 100% better, no vibrations other than expected road vibrations.

 

[SyndicateZ]

Driveshaft?i hope not the camshaft which involved engine teardown

 

[Texas]

Driveshaft?i hope not the camshaft which involved engine teardown

You are correct. I edited! It did take them two months to fix, so might as well have rebuilt the engine… parts were back ordered.

 

[ROBERT BONNER]

You are correct. I edited! It did take them two months to fix, so might as well have rebuilt the engine… parts were back ordered.

Interesting failure. Did they show you the parts or give you any pics?

 

[Texas]

Interesting failure. Did they show you the parts or give you any pics?

They did not. The transmission was previously rebuilt twice due to vibrations, which didn’t resolve the issue (clearly). Apparently Ford took the car back and put the previous owners in a new Expedition and this one found its way through several dealers until I turned into the schmuck who bought it.

No more vibration, so I’m happy.

 

[duneslider]

Rear driveshaft u-joint?

 

[Texas]

Rear driveshaft u-joint?

Yeah, this is the collection of parts they replaced. Part #: JL1Z4602N