I have a '98 F150 4x4 and I'm having problems with brake vibrations and lateral wheel movement on the driver-side rear wheel. I've tried a number of steps (described below) and have run out of ideas. Any suggestions are greatly appreciated.

It started about to years ago. My wife and I only noticed the vibrations and had the drums and shoes replaced a couple of times. We then moved and were towing a car trailer (w car). The vibrations came back and we had the brakes replaced again. The vibrations ceased for a month or so but then returned. Ford and some other mechanics we spoke with had no clue so we decided to live with it. Some months later, while my wife was following me, she noticed the driver-side rear wheel was wobbling. It has been that way about a year and the vibrations recently got so bad that the steering wheel jittered during breaking.

Since we noticed the wheel wobble, I've had new tires put on, made sure they were balanced, and swapped wheels. It's always the rear driver-side that wobbles. I spoke with a number of friends and auto part store employees and it seemed unanimous - rear axle bearing. So, I recently replaced the driver-side rear axle bearing and seal. I had an auto parts guy look at the axle for excessive wear and he said it looked fine and we tested a new bearing and it fit snugly (no play) and there was no visually obvious groove where the old bearing were sitting (nor any cracks or gouges). He suggested I just clean it up with some emery cloth, which I did.

I mounted the tire directly on the axle lugs (no drum) and the tire rotated perfectly. I reinstalled the rear brake shoes and drum and the wobble was back. I made sure that the drums and tires were fully seated and equivalent amounts of lugnut thread were showing on all 5 bolts. I tried swapping the drums, tires, etc., and the wobble always remained on the driver side. So, I used a dremel and cleaned off some rust on the mounting face of the axle and drum with sandpaper. Nothing improved with the wobble.

The major (steering wheel) vibrations have ceased but there are minor ones at 55 - 65 mph speeds if the brakes are applied lightly. I'm not sure if the vibrations now are the brakes reseating or what. Mind you, they've disappeared before only to return.

So, anyone with any ideas on either the wobble or the vibrating brakes? What could it be about mounting with the drum vice just to the axle itself that could throw the wheel off?

I appreciate the help.

- Gary

 

I have read ACE81's post about brake shimmy and the replies to it. So, I also meant to include the following in my previous post:

As far as I can tell, there was no differential fluid leakage from the seals then or now and I followed the Chilton guide in pumping the brakes a few times, adjusting the brakes until the shoes contacted the drums and then backing them off until they just stopped touching.

I considered replacing the drums and shoes again but, given what I'm seeing, any thoughts on whether it is worthwhile or not very likely my problem?

Thanks again,

- Gary

 

It is an option out of left field.....but have you checked the wheel closely for cracks? Or switched it with, like the spare to see if that helps?

 

Yes, I have. I've tried swapping rear wheels and the spare. The problem is always on the driver-side rear. Thanks for the suggestion though.

 

How's the wear on your driver's side, rear tire since you put new ones on? Do you notice any unusual wear?
Did you make sure there weren't any kinks in your ebrake line when you installed your brakes?
Are the springs for your brake shoes in the right holes? I've seen it done.
Did you apply grease to the back plate, so your shoes can move freely?
How do the cylinders look? Pull the rubber boot back and push the pistons in. Do you see a real rusty, greasy fluid? Your cylinders could be bad indicated by what I mentioned before... excessive corrosion causing the pistons to work improperly.

 

Isn't a lateral wobble indicative of bad wheel bearings?