It's not the differential... so what's causing the jumps and bumps?

[Mexicoexpedition]

had the fluid changed in the differential. still jerky when driving at low speeds. mechanic thought it might be the bearings inside the diff? but I'm realizing he's a nice guy but perhaps lacks the experience to deal with my 2000 Eddie Bauer. I'd love to get it working again, but don't want to drive it too far cause I'm told it can lock up. could it be wheel bearings? any help is appreciated cause they want to charge me another 900$ to take the axel off and I just don't the money to put into it. It's too bad, the truck is awesome and only has 130k. any help is appreciated!

 

[Expd830]

What fluid was put in the differential?

 

[02Sexpedition]

U joints

 

[studabaker]

+1 u-joints

Put a jack under your diff housing and spin your rear wheels. Chalk your front tires. Be on level ground. Just lift the wheels slightly off the ground.

Spin the wheels and listen. Brakes? Sway bar?

 

[02Sexpedition]

Definitely u joints

 

[studabaker]

U-joints are relatively easy to repair, they are what makes the axle swivel. It is just a clip and pressure that holds it in place. You will need something to press them out and in. They say to mark the axle as you remove it to replace it in exactly the same position. I have done them myself.

 

[02Sexpedition]

Yes, you will definitely want to mark the collar and the drive shaft before removing. They are “balanced” from what I understand and will need to be reinstalled in the same location.

A vice and a socket works great for pressing out/in. Just make sure it’s flush and the socket is small enough to fit in the hole and big enough to cover the entire cap area of the u joint.

If you Don’t have a vice. A hammer and socket will work, bit more challenging.