How to: How to: Diagnose Driveshaft and U-Joint Problems

[DB_1]

Scary stuff, so what was the cause do you think...rompin' on it too hard or something?

 

[ExplorerDMB]

rompin' on it too hard or something?

always a possibility. To be honest, I don't know - I just do the work.

-Drew

 

[staceyas]

2002 Sport Trac driveline vibration

I recently replaced the u-joints on my 2002 explorer sport trac and failed to index mark the parts before disassembling. I reassembled everything and ended up with a vibration at certain speeds. I removed the shaft again and tried several different clocking configurations but could never seem to get rid of the vibration completely, although, it did seem to change it each time I changed the clocking. My guess is that I put one or both of the yokes back together backwards and so changing the clocking wont help. Anyone have any ideas of what I can do to resolve this problem?

 

[IZwack]

Take it to a driveshaft shop and have them balance it.

 

[staceyas]

Would that be something they would do while it is still installed on the truck or would I remove it and take it to the shop? If I have to remove it , how do I put it back on and know that it is balanced with the transfer shaft and the pinion shaft or does it even matter?

 

[EastoutWest]

I just replaced one of my rear shaft u-joints. The symptoms were: squeaking at very low speeds, vibration under acceleration, and heavy vibrations around 70-80 mph.

I'm sure glad I did it cause when I pulled the drive shaft off, the rear u-joint was so stiff on one axis that it barely moved with considerable coaxing. Also, just a slight movement on the joint produced the same squeaking noise. The front u-joint moved freely without any noise.

Before removing the shaft, I marked the bottom of all parts of the shaft with a paint marker, used the parking brake, and put the 5-spd in gear so neither the transmission end or the diff. end would move. Removing the bolts (4x4s don't have a yoke that slides into the transfer case, instead bolts) was not bad after soaking with PB. I used a 12 point 12mm socket (or was it 1/2 inch?) and a 1/2" breaker bar, then a 3/8" ratchet. It took some creative arm routing to get to the top bolts, but again, it wasn't too bad. Took me 15 min.

Getting the old u-joint out was a bear of a job. I called a few shops and most of them wouldn't replace it if I just brought in the driveshaft... wanted to r&r the shaft for liability reasons...

In removing the old joint, I first bent a big 8-inch c-clamp, then pounded on it using the two socket method with only about a mm of movement... fail. So I called a friend and found out he had a vice I could use (note: when using a vice, be sure to support the other end of the shaft). The two socket method: put a socket that has an outside diameter (O.D.) slightly smaller than the bearing cap on one end and a socket with an O.D. slightly larger than the bearing cap on the other side of the joint. Note: this vice wasn't big enough to use two sockets so I had to use a bolt instead of the smaller socket. Use the vice to press them together. It was barely budging so I tried adding heat with a torch... didn't help. Eventually I found that if I apply pressure with the vice, use plenty of PB, and hit the ears of the driveshaft with a hammer, it would break loose a little at a time. It took several cycles of this method and over an hour to remove the u-joint.

I finally got the old u-joint out and as stated by IZwack, one of the bearing caps was rusted and filled with rust dust rather than needle bearings... I was driving on borrowed time and I'm sure another thousand miles or less and I would have dropped the driveshaft while driving.

I also noticed that a couple of the holes in the shaft's ears had sharp barbs inside them so I used a file and ground them smooth. After all that, getting the new u-joint in was a breeze. Just remove the bearing caps from the new joint being careful not to dislodge any of the needle bearings, position the joint in the driveshaft's ears, lay that end in the vice, start the bearing caps into the holes and press them together. I used large washers when pressing to prevent any damage to the caps. Then when they were flush with the ears, I used the same bolt with a smaller O.D. to press them to the right depth (to clear the channels for the retainer clips). Installing the new u-joint took maybe 20-30 mins. I opted for the greasable u-joints, which were cheaper anyway...

Reinstalling the drive shaft was also pretty easy. Start with the front end, then the back, being sure that your marks are oriented the way they were when you removed the shaft. Haynes said to tighten to 10-16 lb/ft. I thought that was pretty low so went up to about 20 lb/ft.

This was the first time I had replaced a u-joint. Overall, it took 3-4 hours, including about a half hour for calling a few shops and then locating a vice. I bled twice, but nothing serious. The worst part was by far removing the old u-joint. The rest was easy. Now my truck is smooth under acceleration and at speed, with no low-speed squeaking (except for the shocks... maybe another time). Also, my clutch chatter has disappeared...

Hope this helps someone.

 

[DeRocha]

Glad you caught it in time and got it all back together. To make it easier to reach the bolts on the drive Shaft I support the entire rear axle on jack stands. With the wheels off the ground and the others chocked I can shift into neutral and rotate the shaft so the next bolt is in the perfect position for installation/removal.

To make it a little easier next time you might look into picking up (Free AutoZone Rental) the U-joint press. It's designed specifically for the job and can get it down in much less time.

See Stu Olsen's page on using the tool.

 

[emberswzd]

I have a 2001 explorer xlt, 4 WD. Mine has a intermittent squeal in reverse and the same squeal in drive up to about 25 MPH then stops. Before throwing some WD-40 on fwd and rear U-Joints it also made a loud twanging noise when I hit accelerator. From inside cab it sounds as if it is coming from front end but neighbor who was outside said it was coming from rear of truck. Now I also noticed with 4WD the drive shaft does not slide out of trannie, u have to remove 8 12 MM, 12 point bolts from fws and aft ends of shaft. I am hoping I am right that it is a U-joint issue. I went in and out of 4WD high and low but has no clunk when puttig in gear.

 

[mr cribb]

Hmmmm.... this might solve the minor vibration I have. I have that same squeaking up to about 25mph. I just replaced the trans mount today in mine and that took care of the horrible almost unbearable to drive vibration.

The only checking I had done for the u-joints was to see if they were really sloppy feeling. I guess I was going about this all wrong.

Mine is 2wd and I had figured the vibration was due to the excessively worn out front end (waiting on tax time to tackle that) but I may be replacing u joints shortly.

 

[faster340]

I am feeling a vibration or roughness @ 40-60 mph under load. When I left off the gas the vibration goes away.

 

[mr cribb]

Wow I hadn't realized that I hadn't updated on my findings.

Replacement of the u joints solved the issues I reported on 3 years ago.

 

[Sishosonke]

Hi.
I see the ABS. Signal what would be the problem then.
Tnx
Abraham

 

[alberta26]

I just brought a ford explorer for $700 the dryer shift bust the transmission. Now I'm paying 850 to get it fix am I wasting my money