Good Evening everyone,
I have an 02 F150 super cab Fx4 with a 5.4 engine. Earlier this week my wife pulled up to a stop light and the truck began to buck and jerk while moving. She pulled over and we had it towed back to the house. I pulled into the garage and something felt off, my first thought was rear diff clutches(the truck has 92k). I backed it straight out of the garage the next morning and it was popping and binding while backing up, it would move a little then act like it was up against a curb, then hit the gas, it would pop and move a little more. I popped the rear cover off the diff and the fluid was clean, and I did not see any metal shavings in it. Next I removed the rear brake disc to check if the parking brake shoes grenaded, they are fine. Right now I have the rear end on jackstands, I put the tranny in neutral and turned the driveshaft by hand in front of the diff. It will turn in one direction and then not go back the other way. Not to sound ignorant, but is that normal operation of the traction lock diff? Next thing, while turning the driveshaft by hand, there is a clicking noise coming from the transfer case area. I slid underneath and could hear it coming from the case. Is this noise normal? I have no other truck around here to compare too. I have used the search function here at the forum, I am just not finding my particular issue. The truck was not in 4wd when this happened either.
Thanks in advance,
Marty

 

Marty
not sure what going on here either....but if you got this on jack stands (all 4 wheels) and you can't turn the drive shaft both directions just as easy one way & not the other...somethings not right, locker or not. My first thought is the E brakes causing trouble, but you already checked that.

SO, I'd probably disconnect the drive shaft off the Tranny....the retry the rotating of the drive shaft (by hand). if you can get the rear end to turn just as easy in either direction....then I'd say the drive shaft and back is fine & that the issue is either in the T case or tranny.

Does the T case have the correct fluid level in it?
Do you have a limited slip differential?? Did you put the friction modifier in?? the modifier can break down over time and get noisy...but had not heard of binding as your describing unless the those clutch pacs are toast

the only thing else that might be the issue is that the brake calipers are not releasing.

 

Thanks for the reply. Yes I do have limited slip, with 3.55 gears. I haven't checked the t case fluid level yet, I will this afternoon. I am going to double check smoothness of the ebrake engagement and disengagement and pull the driveshaft off and spin as you suggested. I was pretty much hoping the ebrake angle was going to be the sure fire problem.. I will report back later with some findings.
Thanks again
Marty

 

Well I was able to drop the driveshaft tonight and the diff turns just fine. The problem must be forward, transfer case or transmission I guess. On to the next.

 

don't rule out the U-joints....it would be best just to put new ones in especially the one you took apart. re grease the slip yoke too while you're there.

might want to take a good look at the tranny mount....sometimes it can degrade and will cause problems, usually it is in the form of broken or cracked exhaust manifolds.

It still could be something in the tranny or the T-case....but another thing to check is the rear leaf spring bushings & make sure the spring pacs are not moving

 

I'd look at the u-joints closely. I had an F-250 that had a bad front u-joint and when it was in the right position you couldn't budge the steering wheel....really scary.

 

I did not have very much time to wrench tonight after dinner. I removed the transfer case skid plate and took a sample of fluid. It doesn't look horrible(in my opinion), it is brownish opaque, you can see through it with a light. Doesn't smell great but not horrible. I have to assume that it is original. I inspected the u-joints, nothing that jumped out at me, there was no play when moving by hand, probably needed to yank on them with a pry bar. With the front wheels on the ground the front drive shaft turned freely without any resistance and the rear output shaft now isn't turning at all which would make sense due to the popping and binding when being loaded by the engine. I will have to figure my next move and probably start on it this weekend. Sure wish I had a lift, LOL.
Marty

 

Well,
Now about a month later, I finally found the time and motivation to continue my search. I dropped the transmission pan tonight and am pretty sure I found the problem. Something grenaded, there are metal chunks everywhere in the bottom of the pan. So, it looks like it is time for a rebuild or reman tranny. I would really like to know what grenade. Thank you guys for helping out with suggestions, it was greatly appreciated.
Marty