Hi, I recently bought a 1999 Ford e250 5.4 V8. Every thing runs good, but I notice a slight clunk or bump occasionally when braking or taking off that seems just like the symptoms that the slip yoke needs to be lubed. But it's a one piece drive shaft so there is no yoke in the middle to lube. Is there a different place that needs to be lubed or could it be something else? Thanks

 

I've had the exact same thing for 2years and 80,000 miles. I'll be watching this thread.

Strangely mine will even do it after I pop it into Neutral and coast to a stop.

 

Shall we assume you've checked and double checked your u-joints by now?

 

Look underneath and see if you have a two piece driveshaft.
If you do then drop the rear of the axle from the differential using a 12mm 12pt socket to remove the four bolts.
Pull that down and let it hang while you break the band clamp loose on the black corrugated plastic sleeve in the middle of the shaft in front of the carrier bearing.
Pull back the sleeve and make a mark on one side of the shaft and a corresponding mark on the other side.
Pull the rear half of the shaft out,lubricate the splines with a good bearing or axle type grease.
Line it up with marks,slide it back in and bolt it back up.
You do need to get a new clamp for the boot,a zip tie might work but not sure.
DO NOT put a hose clamp on it,get the proper clamp from Ford or another parts store. It is similar to a cv axle boot clamp.
If you use a hose clamp the weight from the screw WILL unbalance the shaft enough to likely make it undriveable.

We grease these slip yokes all the time,very well might be a tsb for it on yours since most of them have one.

That is usually the issue,and would be the first thing I would do if it came into the shop.


*Edit
Sorry,i'm an idiot and missed that you had a one piece driveshaft.
With it in park physically try to turn the driveshaft both ways and see if the movement is in the trans yoke side,differential side or in a Ujoint.

 

No worries Eddie, I actually already bought the Teflon grease to lube it, then realized it was a one piece and the drive shaft looks to be aluminum, so I don't know if it's been replaced in the past or if that comes stock. I tried to move around the u joint and it seemed solid. I'll check the other two points tomorrow and let you know. Thanks

 

The drive shaft as it comes from the factory is a balanced unit---this is pretty vital to know when/if U-joints are replaced.

If not familiar with this sort of thing I'd find a good local drive line specialty shop and have them replace the u-joints with greaseable pieces from Dana or Spicer. They could also check the entire assembly for balance.