Diagnosing humming sound - wheel bearing(?)

JNewm

True Classic
Hi all--

Hoping to leverage the collective wisdom of the forum to diagnose a humming sound that seems to be coming from the right front wheel of my '81 X. It intensifies as the car speeds up and quiets as the car slows down. It also seems to get slightly louder when I turn car to the right and quiets to basically nothing when I turn the car to the left. (This is while the car is moving--there's no noise when the car is stopped.)

The car is wearing nearly new tires and had a recent alignment done by a really excellent shop that didn't mention having any issues trying to align it. Tires seem to be wearing normally. Neither front tire is rubbing on the suspension or wheel well. The steering wheel doesn't seem to pull either way or otherwise wander while in motion. Steering wheel/rest of the car also don't seem to vibrate (well, any more than a normal X on a highway--this ain't exactly a Maybach).

Everything suspension-related is most likely original to the car, so it's all ~40 years old and has about 125,000 miles on it.

With all that in mind, my very non-expert diagnosis is the front right wheel bearing. But I've never been a huge fan of mis-diagnosing car issues and putting in a bunch of work only to find that it was unnecessary. And I guess I think of wheel bearings as an "if it ain't broke..." kind of thing.

Anyone have any thoughts? Should I go ahead and replace the bearing, or is it more likely the ______________ instead? Thanks in advance!!
 
What you describe does sound like a wheel bearing failing. Bad suspension parts will usually result in clunking noises and sometimes odd and scary steering issues. :)

Jack up the right side of the car to get at least the right front wheel off the ground. Grab the tire with your left hand at 9:00 and your right hand at 3:00. Try to wiggle the wheel. There should not be any significant play. Try it with your hands at 12:00 and 6:00 too. If the wheel can wiggle or wobble, your wheel bearing is going bad.

A failing wheel bearing won't really affect the alignment or steering, so it isn't surprising that the shop had no issues lining everything up.
 
Not knowing your tool set, skill set, etc, I will just point out that in addition to the bearings, MWB sells rebuilt uprights.

Every job is a trade off between time and money. New tools are on the money side, but can be used in the future. I did a rear wheel bearing on my 79 years ago and it went well with the help here on Xweb and because I have a local friend with a large press in his garage. :)
 
Given th symptoms you describe, it would be surprising if the problem were anything but the wheel bearing.
 
Thanks, all! I really appreciate it. Going to head down to the parking garage later to give that wheel a wiggle, but it sounds like unanimous agreement that it's the bearing.

@JimD, honestly, I wouldn't even call it a "skill set." More a random assortment of fuzzy memories from wrenching on various cars in high school. Tools are much less of a problem--I use a local rent-a-lift garage with just about every tool imaginable, incl. a press. That said, swapping in the entire steering knuckle/upright is much more in my (limited) wheelhouse... Thanks for the pointer!

I am a bit bummed--we were planning to drive the Fiat up to Savannah this week, but that looks unlikely as MWB is closed today + these are built to order. The dumb teenager in me says, "Roll the dice! Drive the Fiat! The bearing might last!" Thankfully the wise adult has started to win these arguments.
 
Wheel wiggle test not gonna work on the exxe or any modern car with angular contact wheel bearings. Once the wheel is lifted off the ground unloading the wheel and bearing, angular contact bearings have a design in gap and play which will be revealed. This gap and play is mandatory as it compensates for material and bearing expansion as the whole thing heats up. Eliminate that gap/play and the bearing will fail. Once loaded angular contact bearings are self compensating taking up the "play" and allowing expansion with heating.

If the wheel bearing is making noise, it is time to replace it. Humming sound is the bearing beginning to die, when the sound grows like the car is skating on steel, the bearing is dead and will get worst. Still drivable with the Humming noise, could wait until the noise gets worst.. but don't neglect this if the exxe continues to roll.

Replacing the bearing is not so simple, numerous write up on Xweb on this, do a search. And.... not all current replacement wheel bearing are the same. Some are good, some horrid.


Bernice


Thanks, all! I really appreciate it. Going to head down to the parking garage later to give that wheel a wiggle, but it sounds like unanimous agreement that it's the bearing.
 
Got back from tinkering. The wheel did not wiggle. Bernice, if I'm reading your reply
Eliminate that gap/play and the bearing will fail.
right, that's actually a *bad* thing. Or at least it's not necessarily a good thing. I tried spinning the wheel by hand and *thought* I could hear a faint rumble, but it's kinda hard to hear in our parking garage. Took the car out for a short drive to make sure I was really hearing something, and yep, I'm pretty sure I am.


Hopefully MWB stocks the "good" (not horrid!) bearings... Thanks again, all!
 
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I tried spinning the wheel by hand and *thought* I could hear a faint rumble...

If you're 50/50 on the rumble for a front bearing, try taking the brake pads out to eliminate any scraping noises there and spin the wheel again - should be pretty silent - try both side if you're not sure - always best to double check if you're going for a rebuilt unit :)

On a trip back from Italy in days gone by, I remember starting to hear the tell-tale bearing growl as we crossed the Alps, but it survived fine for the 700 odd mile trip home - not a recommended strategy, but needs must...
 
If you're 50/50 on the rumble for a front bearing, try taking the brake pads out to eliminate any scraping noises there and spin the wheel again - should be pretty silent - try both side if you're not sure - always best to double check if you're going for a rebuilt unit :)

On a trip back from Italy in days gone by, I remember starting to hear the tell-tale bearing growl as we crossed the Alps, but it survived fine for the 700 odd mile trip home - not a recommended strategy, but needs must...
Agree with the above. Take both front wheels off, and spin the hubs by hand. You will be able to ascertain any difference in resistance of the bearings.
 
Just keep driving it. The wheel bearings on the 1500cc exxe are a LOT tougher than most realize. Had then go to where the wheel bearing noise sounded like driving on bare metal.. took the bearings apart, they were not that bad.

The noise could be dragging brake pads or ?

Wheel bearings on the exxe were much smaller on the 1300cc/4sp. They are the same front used on the Lancia Scorpion-MonteCarlo, rear wheel bearings are the same which shared with the 128. The 1500cc/5sp front wheel bearings are a LOT larger and last a LOT longer and a LOT tougher than the ones used on the 1300cc/4sp. Rear wheel bearings on the 1500cc/5sp are identical to the Lancia Scorpion-MonteCarlo which are a LOT larger than the 128 wheel bearings used on the 1300cc/4sp. These bearings are oversized for a car weight-size of the exxe.


Bernice
 
If you decide to tackle this job, don't forget that a lot of the chain auto parts stores have loaner wheel bearing R&R tool kits. A LOT of newer cars use this kind of double-row ball bearing.

Another point is that to do a good job you will need more than just the wheel bearing.

A. An electric/air powered 1/2" or better impact gun will come in handy to remove "the big nut"--but not necessary as the nut is on the spindle so loosening it with the car's weight on the tire plus maybe some additional road-hugging weight from "plus-size" buddies :) should be doable. It's specced at 159 ft-lbs so a big-ass breaker bar and a hefty socket is advisable, not to mention a torque wrench that can read that high for re-installaton.

B. There are a lot of little items that go along with bearing like a dust ring, two seals, a snap ring, and a new big nut. A lot of that gets mangled during disassembly. If you favorite US-based vendor does not have all the pieces, you might consider the option of buying a full kit from a European source and if the included bearing is not a recognized quality brand, just get a good bearing from one of our US vendors.

C. In most cases replacing the bearing will not affect the alignment that you recently had done. If your alignment shop used eccentric bolts to adjust your camber, and you choose to remove the strut from the upright, disassembling the strut from the upright will disturb that setting, so if you do go this route, at a minimum precisely scribe the position of the strut "foot" as it meets the upright.
 
Update: replacement is done. It was indeed the bearing! I ended up replacing the whole knuckle, as they're only a couple hundred bucks and it saved me some lift time at the garage. MWB does a really nice job reconditioning the knuckle itself. The humming/howling is gone! Thanks so much to everyone who offered advice and encouragement above!

What did I learn? Well, nothing that any of the experts around here don't already know, of course. But it was a new job to me, so it was fun getting to learn some stuff along the way.

(1) A bad wheel bearing can affect brakes. I was thinking the rotor was warped or at least due for turning. Don't know why it didn't occur to me, but the bad-bearing wobble can = similar symptoms. That brake was also kicking out a lot of dust, likely for the same reason.

(2) If you've put a lot of pressure on with a ball-joint separator and things still aren't budging, just give the separator tool a tap with a BFH. Magic!

(3) The nuts on the joints can be kind of hard to get on, b/c the shaft itself wants to turn. If you put downward pressure on the rods themselves, though, you can get the shaft to seize and get the nut on. I tried hanging body weight, which worked for one but not the other. On the tie rod ball joint, I had to have a 2nd guy put downward pressure on it with a pry bar while I turned the nut.

(4) I think(?) this job may have affected the steering a bit. I was kinda turning the steering rack back and forth by pulling this way and that on the knuckle assembly throughout the project. Before doing the replacement, the steering wheel was pretty much true--it was straight/level when the car was going straight. But now the steering wheel seems to point a bit to the right while going straight. Not sure if there's a way to adjust that? Or if it will need an alignment? Happy with the results nonetheless.

To top it off, on the drive home, I caught a foxy babe ahead of me at a stoplight in a newer red 500 cranking her head around to ogle the X. Gave her a wave and she smiled and waved back. La vita è bella!
 
The tie rod end is adjustable to change the length of the entire tie rod, this affects the steering wheel and more specifically the alignment. You should have the car properly aligned so the car handles properly and you don’t wear the tires out prematurely.

A trick for tie rod ends or ball joints is to use a set of 6” C Clamp Vice Grips to apply the force.

It is done like this:
  • Insert the tie rod end or the balljoint into the knuckle.
  • Spin the nyloc nut down until it hits the nyloc material and of course the ball joint shaft or the tie rod end shaft will start to spin.
  • Put the socket on the nut.
  • Now using the vice grips, put the one leg along side the edge of the socket and the other leg on the top (bottom) surface of the tie rod or ball joint opposing the shaft of the afore mentioned object.
  • Clamp the vice grip
  • You can now tighten the nut.
The tool you want to buys is this one:

https://www.lowes.com/pd/IRWIN-VISE-GRIP-Original-6-in-Locking-C-Clamp-Pliers/1000236031 also available in many other places

8A585BC7-F646-4510-9A72-4410DED1755B.jpeg


It can also be used to compress the front calipers on nearly all cars and rear calipers on cars that don’t have the emergency brake as part of the caliper.
 
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