Grinding noise at low speeds

[Jon3laze]

93 4runner 6 making a grinding noise intermittently at low speeds only. From the research I've done I'm thinking U-Joint or wheel bearings. I recorded a video of it and will post below. I'm looking for input from people more knowledgeable than I to isolate the issue and then possible resources for fixing. Any assistance is greatly appreciated.

https://www.youtube.com/watch?v=v3LyYAvLbVk

 

[KidVermicious]

That could easily be a bit of gravel trapped between the rotor and dust shield.

 

[fourwd1]

Don't drive at low speeds.







Couldn't resist

 

[Darrie]

The speed of the grinding noise sounds to me to be consistent with a wheel rotation ie the noise cycles with one revolution of a tyre, rather than a U joint as the shaft spins at a different speed. It sounds low frequency, not a whine, or a howl like transmission. Driveshaft u Joints give a grind or chatter, but the cycle of the noise seems too slow for either of these.
See if turning the steering wheel to load/unload the front makes any substantial difference - may point you to what end to look at. Diff noises and shaft issues are the hardest as the noises come more central from the vehicle.

So some things to look at
1) Rotate each wheel elevated & listen. Check all the wheel bearings have no play or grind.
2) Take the front wheels off and blow out rotor cover and pad area. Check the rotor has no scrape marks indicating something touching it like gravel.
3) Check the Rear brake linings that no springs off, all linings good - anything free floating in there can grind.
4) Rotate & check the Front CV joints for dry or failed CV's.
5) Drop the front & rear diff oil and inspect for shavings. If not teeth, worn carrier bearings can give you a low pitched rumble. Not sure what the bearings are called on the side of the front diff.
6) For the sake of it check all your engine, transmission & exhaust mounts - even one failed can shift the motor under load making things touch that don't normally ie tailshaft on tank guard.
7) Front pads and calliper issues can give you some random grinding noises. A rusted lazy pot in the calliper can fail to back off when brakes are applied shifting a pad in its seat, even binding it against the rotor. Try a big section of open road starting and slowing not applying any brakes - if no grind, then start using brakes & see if grind appears then that's your tell tale sign.
Hope this helps, Darrie

 

[sisocraN]

Same issue with my 95...have you resolved yours yet? I had the wheel bearings replaced thinking that was it and the noise is still there. Really hoping it's not a bad CV.

 

[flagbasher]

Mine started making a similar noise at low speeds and when turning left.

I took off the front driver tire, and lifted the hub up and it sounded like the upper ball joint was clanking around a bit.

It also coincided with some additional steering slop.

 

[sisocraN]

So I just brought mine in for what sounds like the exact same problem. I drove away poorer with new wheel bearings...and the same sound. Turns out it is either my speedo cable or the cluster itself. (Toyota carries the cable, clusters are out of production/stock). Sounded like it was coming from outside the vehicle, under my feet, but that wasn't the case.

I crawled underneath, disconnected the speedo cable and the problem was solved. For now it's hooked back up. I can tolerate the noise knowing I'm not going to lose a wheel or something catastrophic. When the cable/cluster does fail, I found an android speedometer app which is dead on. Long term, I'll go with a GPS speedometer from Amazon which are surprisingly cheap....that is unless someone out there has a spare cluster laying around???

 

[flyinhawaiian01]

You could also try a slight amount of oil down the cable from inside the cab.

Pull the dash apart to get to the cluster. Once you have the cable disconnected from the cluster, get some oil down the cable and spin/jiggle the cable from the transmission side (disconnect it from the trans and work it from the dash). Once you get a bunch of oil down the cable, connect the trans side back up.

Next, drop a slight amount of oil onto the back end of the speedometer where the cable connects. Try to let it penetrate around the edge of the metal part while you work it around with your finger. Put it all back together and see how it works.

I had loud squealing from the cluster probably about 10 years ago, it mostly happened when it got cold (below 50ºF). After doing this, the noise went away completely for a few years. Did the same thing again, using some lightweight oil (Marvel Mystery Oil), and I haven't heard the squeal since.

You could probably use any sort of oil, but try to use something that will last a while, as penetrant-type oils (WD40, PB Blaster, etc.) dry out relatively quick, making the sqeal come back with a vengeance!

 

[sisocraN]

And now I know what I'll be doing this weekend.

 

[sisocraN]

You could also try a slight amount of oil down the cable from inside the cab.

Thank you for this flyinhawaiian! I had time this weekend to dissect my dashboard and after doing what you suggested, it seems my problem has been solved. The back of the speedo and the north end of the cable were covered in what looked like rust-colored paste, I can only assume it's 20 year old lubricant. After thoroughly cleaning it up, I liberally oiled the back of the speedo. While that sat, my son turned the cable while I got as much oil down the cable as possible.

This was a great opportunity to replace bulbs and thoroughly clean out the air ducts. Funky.

Best of all, the obnoxious noise appears to be gone.