Ford Powerstroke Diesel Forum banner

1 - 9 of 9 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter #1
2002 F250, 8 inch lift w/ 37's
Manual locking hubs

Ok so my truck has no issues in 2wd even with hubs both locked or when in 4x4 hi/ low with hubs UNLOCKED.

BUT as soon has 4x4 system is in action as I idle forward there's a massive clunking and binding sound like a sledge hammer bouncing off my front diff./ drive shaft. But there's no physical binding of any components that I can see! Just a rhythmic and consistent thumping.
When you turn the wheel either direction the sound intensifies.

I even dangled from the side steps as my buddy rolled forward to observe the situation.
 

·
Registered
Joined
·
8,589 Posts
if you have a 2 piece front / rear drive line try this:

when you look at the 4 ends of a u-joint on both dif side and t-case side stick a long 2x4 and law it on the matching end of the u-joint on each end.

so there are 4 u-joint ends on each end of drive line match the #1 on dif end t0 #1 on t-case end if the 2x4 does not lay flat on both u-joint ends you need to remove the yoke and rotate then slide back in to make the ends lay flat or you will get clunking. I didn't have a better way of explaining this sorry...
 

·
Registered
Joined
·
35 Posts
sounds like your u-joints on the front axle. Take a large screwdriver and lightly pry up/down inside the joint, then rotate the axle a quarter turn-you're looking to see if the knuckle has any slop. If so, the u-joint is bad.
Its fairly easy to take the axles out and if you dont want to press them out/in yourself, NAPA usually does it for $20 if you buy the u-joints from them.

See if you have any slop first. You could have a buddy put the truck in reverse and you could kneel down by the front bumper and as he eases off the brake, you should hear and maybe could pinpoint where the sound is coming from.

Good luck and let us know.
 

·
Registered
Joined
·
4 Posts
Discussion Starter #4
I feel like bad axle U joints has possibly been removed from the list of potential problems, I removed both axles and serviced the front diff I replacing the axle bearing inside the hub (that one little part you can actually change in the non-serviceable hub)and the outer hub seal, you know that big one that's inside the knuckle with a little bearing in it. and also did the axle dust seal. The U joints seemed fine, had them in the vice grip looking for unnecessary play. But they seemed smooth

But what you said about the drive shaft, it makes sense about lining up the u joints but your taking about the yolk on the differential side as the.one you slide out right?
 

·
Registered
Joined
·
8,589 Posts
yes the shorter end on front that connects drive-line to the dif. you can remove it and turn it to get the u-joints to line up. i re-greased my rear slip joint and didn't get the u-joined lined up and for few days heard a light clunking at like 3-7mph when stopping. got a 2x4 up there and just rotated the outer/ shorter slip yoke to match the u-joints and now smooth sailing.. a sledge hammer sound is pretty intense though...

1. when you serviced the axles did you put the full synthetic in? i know the limited slip needs that or the disk get burnt up or something etc..
 

·
Registered
Joined
·
4 Posts
Discussion Starter #6
yeah i used Valvoline full synthetic for LS, you just took the front u joint apart and moved the drive shaft over to slide the yolk out right?
 

·
Registered
Joined
·
8,589 Posts
there should be to small kinda half-circle clamps on front of drive line hold u-joint to differential. 4 like 8mm bolts i think and then you just rotate it and slide it back on once you got u-joints on front lined up with u-joints on rear of front drive line.

when you grease the slip joint (part of drive line that has the splines) use fords blue synthetic grease it has like silicone in it and does way better job then grease from autozone.
 

Attachments

·
Registered
Joined
·
4 Posts
Discussion Starter #8
Ok cool hopefully when i get home from vacation the u joints are infact misaligned thanks for the tips much appreciated!!


But incase that isnt the issue anyone else with similar problems let me know your solution please!!!
 

·
Registered
Joined
·
8,589 Posts
no prob man have fun!
 
1 - 9 of 9 Posts
Top