Hi guys, about a week or two ago my truck started to shake bad, at first it was most noticeable when braking but has gotten steadily worse. Today I had it up on stands and put it into gear. With rear tires spinning freely it was obvious it's where the driveshaft enters the rear diff, lots of play making the whole rear axle bounce badly. Is this a bearing and seal repair? Is it a DIY thing or best left to the professionals? Funds are low so would like to fix on my own if possible. Thanks for any input.

 

Year and model? 1 piece or 2 piece driveshaft? Limited slip or open diff? Is the play in the diff or is it the u-joint?

 

Sorry for lack of details..2008 F150 4x4 with 5.4, 1 pc driveshaft, limited slip diff. It's not the u joint, the movement is like slopiness as shaft is rotating in the diff if that makes any sense

 

Any whining or grinding noises? Sounds like a pinion bearing. However, the diff will probably need to be taken apart by someone who knows what they are looking at.

 

When accelerating no noise whatsoever but when off the gas or just coasting downhill it was growling yes. Not sure why it isn't noisy all the time?

 

That's the pinion bearing.

 

Thanks, after watching a couple of vids I think its more than I can handle at my age. Guess its going into the shop. Thanks again, I appreciate your input