alsatropine

iTrader: (2)

The bump your feeling is a miss fire. I'm tackling the issue possibly this weekend. As far as the humming, does it stop when you let off the accelerator? Only do it above certain speeds? If so it sounds like the carrier bearing in the rear diff. I've been told by numerous mechanics just to let it ride until the noise changes .I've been riding for over 20,000 miles with the humming noise .

atnolan94

The humming and the thumping happen simultaneously. And I had the rear diff rebuilt and it didn't help a ton. Yes the humming stops if I let off or if I really lean into it its that mid-throttle position that it'll happen when beginning to accelerate between 45is and 6ish mph. So for example if I hit a hill going 50 and have to lean in just enough to keep speed it'll hum first then the bumping starts immediately after. If I let off it'll stop and if I lay into it and downshift it will also go away. But the hum will follow the RPMs up but go away once the shift is complete.

Either way a set of 8 COPS is coming in this weekend so I can throw them on Sunday afternoon and hopefully that does it. I wasn't wanting to spend $300 on a set from Motorcraft. I went with the 1A Auto ones because they really stand behind their product. I read up a lot on it and most people were saying they had luck with cheaper brands than Motorcraft.