Since when did I have MTs? (1 Viewer)

[Jman]

My 60 just developed a rumble in the back, like I've got mud tires. Slows down/speeds up with tire speed, not related to engine speed at all. When I lightly apply the brakes, the rumble disappears entirely.

It sounds as if it's coming from the left rear, but I could be wrong--haven't had anyone in the passenger seat the past few days.

Truck has 173k on it.

 

[Doc]

Check the odvious first. Brakes might be dragging or have some debris between the pad and rotor.

 

[Mike S]

Unlikely to be something between the pad and rotor, since the 60 has drums in the rear... brakes or bearings is my uninformed guess.

M

 

[Jman]

Unlikely to be something between the pad and rotor, since the 60 has drums in the rear... brakes or bearings is my uninformed guess.

M

Rear brakes were done about 3k ago, so I doubt it's that.

How many is rear bearings? I work curbside. And how long can I let this go before something gets totally fawked?

 

[swank60]

If it were bearings, wouldn't there be some other signs of a problem? Like a blown axle seal leaking grease into the pumpkin or all over the inside of the wheels? Doesn't really seem like they'd just 'fail' - but that sort of noise does seem like trouble.

Plenty of oil in the rear end?

 

[soggy60]

I too suspect rear bearings.

cheap test: lift axle at spring/shock mount pad. parking brake off. try to lift tire : if bearing, you'll feel it

If its bearing: Two things will happen if you ignore it long enough.
1. axle seal will wear & leak. 90wt in brake area not good . . .
lemme tell ya how I know . . .

2. (if ya go really long) bearing failure, also not good.

One bearing each axle.
bearing 'pressed' into axle tube.'slide hammer' bearing removal tool works real good - rent one...
press in new bearing with rounded block of hardwood & BFH.

 

[Jman]

Plenty of oil in the rear end?

Hmmmm, maybe I don't have any oil in the rear end. I know you have plenty in yours, though.





























Sorry, couldn't resist. I was wearing my finest monkey suit this morning when it cropped up--wasn't about to go crawling around looking for grease/oil.

 

[swank60]

Well, I had to ask.

The reason that it came to mind is because years ago, the rear end of my Spitfire went out, and it made a weird, vibrating, MT tire sort of noise. And since the rear end was about 6" from my back, I could feel it, too - not like the 60, where the rear-end is 6' away.

Start with the easy stuff first - check the oil in the rear end, then lift it up on a jack and see if your bearings wiggle. Can't hurt.

 

[BigRed87]

you might check to see if you threw a some tread on that tire.

 

[baumber]

U-Joint?

Another check.... Rear u-joint.

Alot of times-- and correct me if I'm wrong-- a bad u-joint will be noticeable only when the engine is telling the axle to turn. The stress on the joint under pull will give you a rumble. Apply the brakes and the stress is gone....
Which means if you do some engine braking instead of pedal, it should still be noticeable

 

[Jman]

you might check to see if you threw a some tread on that tire.

Now THAT I did check, since it's happened to me before (same wheel, too). The whole tread peeled off, tire stayed inflated, was riding on the belt--at highway speeds. This time tire looks fine.

Since braking stops the rumble, I'm thinking it's the bearing--the dampening effect of the calipers steadying the wheel.

But I'll check the rear diff, too.

 

[Tinker]

Does it go away turning one way or the other? If so, it's probably the bearing on the outside of the turn that makes noise.

To pull the axle you have to remove the diff inspection cover, remove the pin bolt, spider shaft & block, push the axle in, & remove the C-clip. Then you can use a slide hammer bearing puller to get the bearing out (seal will come with it).

 

[Jman]

Does it go away turning one way or the other? If so, it's probably the bearing on the outside of the turn that makes noise.

Bingo! I noticed a while ago a little vibration, only when turning right at highway speeds, it never amounted to much so I ignored it. Now that I've got a rumble at low speeds on the driver's side, I'm sure it's my left rear bearing.

Thanks.