Wheel Bearing Failure Causes

Sounds like brakes were stuck

 

Hub out of oil from wheel seal leak if it is oil bath. Probably had wheel seal leak. That could be from various reasons. The nuts could have backed off a little and allowed the bearings to be out of adjustment also. If a wheel is adjusted properly and full of oil it should run forever.

I have seen seen many drivers with wheels run off like this. Have to do that per trip and you have to pop the caps and go under truck and trailer every weekend. After you pop the fill cap look in there for discoloration. Peek in between shoes and look at those seals. They usually warn you before they do like his. And always check for play in bearings when you jack wheels off the ground for any reason.

I had had a truck in the shop the other day and I leaned against it while talking to someone and could see it move. Everyone else in shop said I was full of it but we jacked it up and sure enough it was loose.

 

I even saw one truck that another mechanic had put the nut with the stub on backwards and it caused bearing failure. That wheel assembly came off and killed another trucker.

 

When bearings fail like that they also destroy any evidence of what happened to cause it. If a driver performs his precheck properly, the hubs should have had enough oil in them and no signs of wheel seal leaking. It is rare to have a seal fail while in motion like that and have the oil drain completely out to cause this. Bearings can survive rather well with low oil. When bearings start to fail internally, the rollers generally start to go over time and cause excess end play, which leads to wheel seal leakage, again this should be caught on a pre trip check. One thing that can happen fast, kinda like Pool6710 is saying, is a maxi can let go/leak or a shoe stick and cause brake drag to the point where the heat destroys the wheel seal and all the oil leaks out quickly and causes a catastrophic bearing failure.

 

I lost steer on cabbage several years ago. 6 months before that I had new kingpins and new wheel bearings. First they tried to blame me for letting it run dry. I had them take the other side off and check it out. That wheel would not have lasted long. You would think mechanic error, I watched the whole install. It turned out to be counterfeit
bearings. The original installers treated me well, motel, car rental, repairs and downtime. I should say their insurance company did. There are counterfeit parts out there.

 

When I drove, stopping and feeling every hub, was normal, also checking the oil level when doing the pre trip. If you are wondering if the seal is leaking a tick I found was to take a wire-tie, and bend the end a little more than it is and thru the slot in the top of the dust shield, slip it between, the blocks of the shoe, all the way in, if it comes out oily, the seal is leaking.
An inferred temp gun is a great thing to have, you can measure the tempature without touching it. one other thing most hub caps have a plug on the side, it has a magnet, when in dought remove it, and clean it, if you do one a week if one comes up full of metal it will have saved you a large bill.
If you are an owner operator, then every once in a while, or even say once a week you jack up one wheel, and with a long bar thru spokes, lift, any movement it needs to be removed and inspected, many will only need to be readjusted if the hub has silver in it, then you want to pull the hub and inspect the bearings. If it has an aluminum hub you want to weld a bead around the race to remove it.
I use a mustard container, the ones with the pointed tips, with 90W oil in it to fill the hubs, they shut off and do not leak.
Just a thought!

 

This is what I was thinking. It happens on other types of lighter vehicles too. Dually trucks, dually trailers with electric brakes, etc.

I've also seen children/people remove the rubber fill plugs for reason(s) unknown which reinforces the need to pre-check after being stopped somewhere. Dexter screw on axle caps also commonly loosen on the drivers side because the thread is normal, not reversed. Need to check that caps are tight or bolted down properly.

 

Sometimes these things happen with no warning. But, many times there are signs that a failure is going to happen. That's why I think All drivers should grease their own truck. Get under it and look things over. Speedco and other shops are not looking for the little things that turn into big things.

 

Good suggestion on the mustard bottle.