snapping in the rear end

abbottfarms · Jul 4, 2012

Today the wife's truck (2004 F-250 ECSB 4X4) started making a snapping sound from the rear end, only noticeable under 20 mph. Doesn't matter if you are going straight or turning, still the same sound, and it doesn't do it every time either. When you grab the tire, (either side, both with same results) and shake it there is a a clunking noise that I assume translates into the snapping you hear when moving. Rear end is full of fluid. Any idea's what it might be?

youngstroker · Jul 4, 2012

Have u had the u joints changed lately?

abbottfarms · Jul 4, 2012

It's not the u joints, it's in the rear end itself. Like I said with the truck parked pushing in and pulling out on the rear tire makes it clunk, so I am assuming what ever is making it clunk parked is making it snap when driving.

youngstroker · Jul 4, 2012

Check the drive shaft to pinion bolts they like to back out a little, ford lock tights them from the factory and if the are removed and not relock tighted they may loosen up. All rear axles make a clunk noise when rocked back and forth, with out hearing it I cant say it is excessive or not.

abbottfarms · Jul 4, 2012

it clunks a little more then my truck does but not excessive, but I will check those bolts in the morning, just did a pinion seal on it a month or so ago, so it could very well be that they have loosened up some, hadn't though of it glad you mentioned it.

youngstroker · Jul 4, 2012

Been there done that :thumbsup:

Stroker#66 · Jul 4, 2012

Wonder if you over tightened the pinion nut when Putting it back together

abbottfarms · Jul 4, 2012

Doubt it. Just looked in my maintenance records and it was 6 weeks and 4,700 miles ago. If it was over tightened I would have to think it would have started bothering long before now.