2010 LX570 Wheel Bearing? (2 Viewers)

[gryphen]

I've recently returned from a trip through the WA mid-west, nothing too rough, bit of gravel is all, and towing our offroad van (under 2000kg).

I had been back for a couple of days took a drive for coffee (12km at 60kmh) and could smell hot metal from the passenger rear wheel hub. Drove home after a while and the hub was too hot to touch compared to the other 3 corners.

Put it into Lexus for a 160k Service, Brake rotor shim, new pads, and advised them re the heat. Their mechanic suspected an incorrectly adjusted handbrake, so they did that, and repacked the hubs etc.

Took it for a drive yesterday arvo, same 12k at max 60kmh and a lot at 40kmh (school zones), no appreciable smell, but when I used my little temperature gun on the hubs found that the passenger rear hub was showing 72 degrees C, whilst the other 3 wheel showed and average of 49 degrees C.

I took it for a short drive (4.3k mostly 60kmh with one section about 1/2k at 70kmh) this morning and the hub showed 49 degrees C whilst the other 3 wheels averaged 19 degrees C

To the tech heads in the room, am I right in suspecting a wheel bearing is on the way out?

Or is there something else I am missing?

Thanks in advance for any advice proffered.

 

[bloc]

Where exactly are you taking measurements?

It is still likely the parking brake is dragging slightly, even for a short time after factory adjustment.

My question would be why it was dragging aggressively in the first place? Does your rig have much corrosion?

I have had to replace a failed rear axle bearing. I never measured temperatures, but there was a very loud rumble at highway speeds. As long as you aren’t too corroded you can pull the ABS sensor from that corner and look at the flat plastic end of it for signs of contact with the tone ring, which is evidence the bearing is failing and letting the axle shaft move laterally.

 

[gryphen]

Where exactly are you taking measurements?

It is still likely the parking brake is dragging slightly, even for a short time after factory adjustment.

My question would be why it was dragging aggressively in the first place? Does your rig have much corrosion?

I have had to replace a failed rear axle bearing. I never measured temperatures, but there was a very loud rumble at highway speeds. As long as you aren’t too corroded you can pull the ABS sensor from that corner and look at the flat plastic end of it for signs of contact with the tone ring, which is evidence the bearing is failing and letting the axle shaft move laterally.

I'm measuring it by pointing the handheld temperature sensor unit at the centre of the hub from standing alongside the car.

No corrosion at all, it's pristine.

I don't have any sounds as yet, just the sudden noticeable smell to start with, and now after the service just the temp as i check it, haven't even tried it up on highway speeds just yet

 

[bloc]

Center of the hub.. wheel center cap removed? Or meaning at the iron hub through the spokes of the wheel?

If through the spokes then you really aren’t getting the temp of the bearing unit, but the brake rotor hat. And in the case of the rears, literally the outside of the drum portion of the parking brake. Any brake drag there will drastically increase the temps you measure.

I get that that one being higher than the rest stands out, but because of the differences in implementation you can really only compare it to the other side, the front axle is irrelevant.

One parking brake deciding to drag all of a sudden is not normal behavior that I’ve read about in years on here.. especially without corrosion. personally I’d want to figure out why that happened, whether it’s in the cable or brake mechanism.

 

[gryphen]

Yer going to take it for a bit longer drive tomorrow, and try taking the temp from different directions under the vehicle to see if I can isolate where it is greatest.

 

[TheComedian]

But could also simply be the new brake pads that still have to grind a little and therefore lead to the slightly higher temperature.
Would be a very big coincidence if on the same wheel where the brake has given up also suddenly bearing problems would occur.
Bc the new pads probably bite also the first few hundred kilometer a bit more aggressive what follows higher temp.

Just me guessing around…

 

[gryphen]

But could also simply be the new brake pads that still have to grind a little and therefore lead to the slightly higher temperature.
Would be a very big coincidence if on the same wheel where the brake has given up also suddenly bearing problems would occur.
Bc the new pads probably bite also the first few hundred kilometer a bit more aggressive what follows higher temp.

Just me guessing around…

I could expect that across all four wheels, and could also accept that the adjustment on the handbrake for that particular wheel could be slightly out, but like has been said why did it happen in the first place, when everything looks fine, and why hasn't it improved somewhat after being worked upon by the Lexus mechanic. Seems to me either the mechanic got it wrong and hasn't fixed the initial issue (he believed it might be the handbrake adjustment being slightly out, apparently it only has miniscule adjustment) or there is another issue that as yet hasn't been fixed. If there was some other bit of info (a noise or brake pulling on the one corner etc) then there would bem ore to go on, and so why i am going for a longer drive and then try and isolate the source of heat.

 

[TheComedian]

I could expect that across all four wheels, and could also accept that the adjustment on the handbrake for that particular wheel could be slightly out, but like has been said why did it happen in the first place, when everything looks fine, and why hasn't it improved somewhat after being worked upon by the Lexus mechanic. Seems to me either the mechanic got it wrong and hasn't fixed the initial issue (he believed it might be the handbrake adjustment being slightly out, apparently it only has miniscule adjustment) or there is another issue that as yet hasn't been fixed. If there was some other bit of info (a noise or brake pulling on the one corner etc) then there would bem ore to go on, and so why i am going for a longer drive and then try and isolate the source of heat.

Uh I see. Missed the point that it is the hand break (too early in the morning hehe). Well just from my point of view - since I already worked alot on the s***ty hand break of my 2008 - I would call out for the star wheel. One click too much can cause the pads to overheat.
I don’t know if you are used to work on your car but I would lift him on the rear and then spin the wheels by hand to see if there is a strong difference between amount of force you need to spin the left and the right. Then you just need to unmount the wheel and open the little star wheel just one click with the screwdriver.

 

[bloc]

The differential in each axle means you can’t just spin one side without the other side spinning too.

Yes the star wheel is a precision adjustment, but it isn’t the final adjustment in the service manual. Per the procedure you do gross adjustment with the wheel then dial in the parking brake handle with a fish scale.

 

[gryphen]

Okay to those who said it might now just be the handbrake dragging after pads being replaced and adjustment you appear to be correct. Took it for a lot longer drive at 100kph parked up, checked the temps and the two rear hubs were exactly the same temp, and after returning home the hubs were all nice and cool.

Thankyou for all the assistance and advice, it is much appreciated.