Vibration in floor pan on hard acceleration and steady highway speed

[kawasaki2374]

I just purchased a1996 explorer limited 5.0L AWD 114,000. I have a vibration at hard accel and cruising speeds pulled drive shafts all good. Balanced tires still vibrates. Its in the floor and it feels like a U-joint so I pulled the shafts replaced all u-joints and still there. FRUSTRATION is setting in. Transmission shifts great, lots of power. Wheel bearings are good any body have any ideas.

 

[Cleaverkid]

I've got the same issue

Does your front driveshaft have a CV joint or all U-joints? My CV joint went back and the repair shop put a replacement in that had all U-joints. It's been vibrating ever since. I'm convinced the U-joint replacement for the CV joint is the culprit, but haven't been able to afford a new/replacement one.

 

[kawasaki2374]

has the u joints. Why did they replace your cv driveshaft and that one had a normal u joint at the diff and the cv at the transfer case?

 

[Cobraguy]

You know, this will drive you nuts. I've actually had to send vehicles under warranty to the Ford NVH Lab to try and find these problems. A couple they couldn't find and bought the car back. The only thing I can suggest is make sure NOTHING is grounding out against the drivetrain. Maybe a body mount is bad and allowing the body to touch something. Then do like you did and check every single u joint and have the shafts balanced. Replace the transmission mount. Don't screw around here...get a Ford mount! You are fighting a problem. You want to make sure you don't get a part that doesn't fix the problem. Check your engine mounts. You can replace them too. And after all that, if you still have the vibration, then it's usually in the transmission or transfer case. Something is wearing and is out of balance now. Like I said...these can be a real ***** to find. Or you can be the luckiest SOB alive and find it in two minutes.