Lotsa new parts...still have vibration!

[derck_mullin]

OK, I replaced the carrier bearing a couple of weeks ago. When I pulled it off the truck it was in bad shape, so I thought that was the problem...no dice.

Today I went out and bought 3 new U joints and when I pulled them, 2 looked fine, but the one that attaches to the yoke on the rear end was full of dirt and crap. So I thought that was DEFINITELY the problem...again no dice. The U joints definitely needed replacing, so I'm glad I did, but still have the problem.

I'm not sure what to try next. Basically when I get to just over 30 up to around 40 I get a really bad vibration. The whole truck vibrates and anything loose in the cab starts to rattle.

Seems to be something in the driveline but now I'm not sure. I guess I could pull the driveshaft and drive around only with the fronts turning and see if that cures it.

Also, not sure if it's related, but when I'm going at a decent speed and in a turn a get a humming/groaning kind of noise/feel. Kinda hard to explain so I don't know if that is related or not.

If anyone knows of something else I should look at let me know. I'm also going to rotate the tires and have them rebalanced. Again not sure if that will help but it's maintenance I need to do anyway.

Thanks!

[derck_mullin]

Well, I rebalanced all of the tires today and rotated them as well. No luck.

We put the truck up on a lift and the left rear rotor seems to be warped so pulled that off and ran the truck up to the speed where the vibe happens and it was still doing it.

Put everything back together and dropped the back section of the driveshaft. I put it in 4 wheel hi and took it out for a spin with only the fronts driving. No vibration...

So...that is leading me to believe it is definitely either in the driveshaft itself or something to do with the driveshaft like the pinion bearing. We tried to see if there was any play in the pinion yoke, but it seems snug. I'm wondering if maybe the pinion angle is off. The truck does have a spacer in the rear between the axle and the leaf springs but the carrier bearing hasn't been shimmed. The spacer is only about 2" thick. Also these have always been on the truck, but it hasn't always had the vibration...can the pinion angle change???

I'll see if I can find out how to check the angle and if that doesn't help I guess I need to look at having the driveshaft rebalanced.

Anyone have any other suggestions???

Thanks!

[ryansmagic]

I'm having this same problem but on a 2wd f250, at 40-48 mph, my truck gets a strong vibration

[derck_mullin]

Strange...thought I posted the fix here.

I used the "band clamp" method and the vibe is fixed. Not sure how, but apparently my driveshaft got out of balance at some point. I'll probably eventually take it somewhere and have it professionally balanced, but for now it's about a 95% solution.

[IHJEFF]

I have the exact same truck with the exact same problem. What is the band clamp method?

[derck_mullin]

Basically you find a band clamp big enough to go around the driveshaft (I think a 4" is what I used). If you can, put the truck up on a lift and put it in gear and look at the driveshaft. Mine was noticeably wobbly near the transfer case. Mark the driveshaft off in 90 degree sections where you see it moving around...I just used a piece of chalk to mark the driveshaft. Then take one band clamp and start with it on one of the marks and tighten it. Restart the truck and run it up and see if that helped. If not, try the next mark 90 degrees away and repeat. Hopefully one of the marks will be pretty close and will take most of the vibe out or make a noticeable difference. Then take a second clamp and put it in the same spot and phase it left and right in small increments until the vibe is gone and tighten it down. Might not get it to 100% but should get it pretty close. Basically the head of the clamp works like a weight that you are moving around the driveshaft.

However, you'll notice I replaced the u-joints and the carrier bearing prior to this so do those first if you haven't already.

[IHJEFF]

Thanks, I will check that out. Did you have any front supension noise problems (rattle after each bump)? I have replaced everything except the spring bushings. Im going to try an aftermarket set of stabilizer bushings even though the oem ones didnt seem to make much difference.

[jc82chevyman]

I mean i know thats a poor mans way of doing it but after you spent all that time jacking with it wouldnt just be easier to take it a driveline shop to have it balance I don't think its all that much