Vibration

[Explosia]

I have a rear vibration that’s driving me crazy. I’ve replaced the carrier bearing, it helped but it’s still there. Curious to know if my shocks have anything to do with it? They’re old and need to be replaced anyways.

[Mattman]

Guessing you checked u joints while replacing carrier bearing?

What about your tires?

[Waterloo]

What make, model, year and mileage?

The shocks could, any odd tire wear? Inspect the u joints? Pin bushings and torque rod bushings up between the frame rails? Depending upon the mileage of the truck, it may just be time for new u joints and bushings, around 800,000 is their life span. If the truck hauls heavy the majority of the time, 600,000 to 700,000 miles to beat a catastrophic failure like Rawze had up in Utah area, it was ugly, and very expensive. Nothing to ignore.

I replaced all of the above at roughly 750,000 miles. The u joints were shot, but they took grease. So a simple visual on those is not always going to be accurate.

I don't haul heavy and put few miles on the truck, so I swap out shocks every two years. Many guys replace shocks yearly, depending on what they haul.

Also, on Merritor rear ends there is a crush washer, it hides behind the yoke in the front differential, it needs to be replaced any time the drive shaft and yoke is removed, one time use. If you don't replace, there will be some play in the yoke/driveshaft, that could cause a vibration. No clue if the other rear end guys use the same setup with the crush washer. If that is the case, Fleetpride is the best place to purchase, half the price of the dealer.

Could be that crush washer from when you installed the new carrier bearing. Not replacing that crush washer can take out your carrier bearing. That is how I discovered it.

Just a few things off the top of my head.

[Explosia]

2015 Prostar...U Joints are good, I didn’t know about the crush washer, I will take care of that immediately. Inside rear axle has heavy wear on the inside of the tire, prolly due to shocks. I’ll have to research the site about the torque rod and pin bushings, not familiar with those. Thanks for your help!

[Lonestar10]

idk what type of wear but according to Rawze the inside tire wear on my truck is most likely caused by the wheel bearings being out of spec and need to be retorqued wouldnt be a bad idea to check yours also.

[SIDE_SHOW]

The wheel bearings out of spec will cause the tire wear as will shocks...

Is the ride height correct? this will also cause a vibration although usually accompanied with a growl...

Is the driveline in phase/ time ? This will cause a vibration...

If you have eaton rear ends the yokes are bad about loosening up at least they used to be I don't know if they have fixed that on the newer models or not....



I would re torque wheel bearings they probably need to be done anyways

Same with shocks replace if you can

Make sure the driveline is in time/phase... I'm not very good at explaining this but all the yokes need to line up maybe one of the other members can explain it a little better

Check the ride height
I'm not sure what the spec is on a prostar but I know Mr rawze does

Chock wheels and release brakes crawl under the truck and move up and down on the rear end yokes if the yoke moves on the pinion shaft it's loose best way to tell is to look at the nut while you are moving it up and down....

Also the crush washer as Waterloo said I have seen this give fits as well.

Thats where I would start... But I'm no expert just what I've had to deal with

As Waterloo said you may just have a u joint that is bad but you can't tell that it's bad until high speed... .