How hot are you wheel bearings ? (1 Viewer)

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Funny question but has anyone measured their hub temperature with an infrared thermometer?
I’ve recently re-torqued my front wheel bearings to around 25ftlb, and measured the temperature. My rear hubs, which i never touched, were 90*, the wheel was 80* and the rotor was around 126*.

My front hubs were at 102* with the wheel being 85 and the rotors around 126*.

This was a 30minute drive in the sun, at 75*.
 
That doesn't sound too hot. I was told not too worry unless they are too hot to touch. Remember the front has a lot more weight = more friction = more heat
 
Sounds cool actually, IIRC last time I could find my IR Thermometer I got around 115'F for the front hubs immediately after a 30 minute 55mph drive with little braking. Rear hubs were cooler.
 
Funny you should ask. Checked the turbo truck for wheel bearing play before I moved it. Super sloppy. Opened the flange and the underside has grooves from the nut backing out. The nut got so hot it welded it to the spindle 😞

5DB425A6-E022-4A50-9726-95F4C231D574.jpeg
 
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Funny question but has anyone measured their hub temperature with an infrared thermometer?
I’ve recently re-torqued my front wheel bearings to around 25ftlb, and measured the temperature. My rear hubs, which i never touched, were 90*, the wheel was 80* and the rotor was around 126*.

My front hubs were at 102* with the wheel being 85 and the rotors around 126*.

This was a 30minute drive in the sun, at 75*.
I see about 105 - 115 all around, with the rears up to 10 degrees lower than the fronts. (front bearings at 45ft/lbs). Last checked after an mpg run a couple weeks ago. 65mph on flattish ground (Springs to north Pueblo and back) for about 80 minutes.
edit: FWIW, ambient temp was pushing 90+
 
I check mine regularly as it helps do a quick health check.

Braking heavily influences the numbers.

Mine typically run 85 to 92 on the hub I don't worry about the wheel. I torque to 35 LB - FT
 
When i’ve rebuilt by axle a year ago, I’ve torques to my wheel bearings to 15 ft-lbs. I decided to check them before SAS2020 and i thought they might have little play but it could have just been in my head. That’s what made me retorque them to 25 ft-lb and i was worried maybe i’ve overdone it.



Funny you should ask. Checked the turbo truck for wheel bearing play before I moved it. Super sloppy. Opened the flange and the underside has grooves from the nut backing out. The nut got so hot it welded it to the spindle 😞

View attachment 2381759

Woah that sucks.
Now that you mention that, I did notice grooves on the bearing washer before the nut. I suspect due to it not being torqued tight enough. Luckily the bearing and race looked good.
 
Not the expert on this, just bringing the topic back up as it happened to my 96 model 10 years ago: if the bearings aren't holding preload, check the spindle tube for wear between the 3 to 9 O'clock position (underside) where the outer bearing rides.

If the OD of the spindle tube at that location is worn (and/or if the ID of the bearing pack inner race has opened up) the bearings won't hold preload no matter how tight you go and it'll happen again. The fix is to replace the spindle, or if money is tight you can "stake" the spindle tube for a temp fix. I did this 70,000 miles ago in my 96 model with good results. FWIW.
 
Hi, I’ve always felt my hub to be barely warm,anything hotter and I repack them. Mike
 
Just ran across this thread. Installed new front rotors and pads this morning on my 80, threw the hubs back together without even really thinking about it since I did spindles, CV grease, wheel bearings, and new drive flanges back in the summer. Put on new lock washers since I had them on hand and I couldn't get the adjusting nut to line up with it anymore.

Did the bearings by feel, as I always do, but now I'm thinking I might have gone a bit too tight.

Gonna go for a good drive tomorrow and use an IR thermometer on my drive flanges. I could touch them by hand after a good drive and break in of the new brakes, but they were definitely warm.

I'm pretty sure I'm ok, and those bearings have about 5k miles on them so I assume they've broken in a bit and require a bit more preload. Idk, I'm probably overthinking it....
 
Just ran across this thread. Installed new front rotors and pads this morning on my 80, threw the hubs back together without even really thinking about it since I did spindles, CV grease, wheel bearings, and new drive flanges back in the summer. Put on new lock washers since I had them on hand and I couldn't get the adjusting nut to line up with it anymore.

Did the bearings by feel, as I always do, but now I'm thinking I might have gone a bit too tight.

Gonna go for a good drive tomorrow and use an IR thermometer on my drive flanges. I could touch them by hand after a good drive and break in of the new brakes, but they were definitely warm.

I'm pretty sure I'm ok, and those bearings have about 5k miles on them so I assume they've broken in a bit and require a bit more preload. Idk, I'm probably overthinking it....
I think that the pads are constantly in some sort of contact with the rotors and that should be the only source of heat in a hub. If the bearing is the source of generating heat, then that bearing will swell and fail quickly.
 
I think that the pads are constantly in some sort of contact with the rotors and that should be the only source of heat in a hub. If the bearing is the source of generating heat, then that bearing will swell and fail quickly.
Makes sense. I'm thinking the hub probably gets heat soaked from the front brakes too.
 
There will be heat from the axle oil which gets very hot, this can be transmitted through to the CV and then to spindle/bearing assembly, then there is the heat from the brake disc, I would not expect much heat at all from the actual bearings assuming they are lubed and adjusted correctly.

Heat building in such a short time and assuming the brakes were not used does not sound good for long term longevity?

Regards

Dave
 
There will be heat from the axle oil which gets very hot, this can be transmitted through to the CV and then to spindle/bearing assembly, then there is the heat from the brake disc, I would not expect much heat at all from the actual bearings assuming they are lubed and adjusted correctly.

Heat building in such a short time and assuming the brakes were not used does not sound good for long term longevity?

Regards

Dave
Yep, gear oil gets hot. Logic here checks out to me. I was driving 70 on the freeway for about 10 minutes then went back home on the expressway doing 50 and hitting every single red light so I guess quite a bit of stopping. I could still put my hand on the drive flanges afterwards; not too hot too touch. Pretty sure all the heat was from the new brakes.
I'm gonna check temps tomorrow and maybe even re-adjust if needed.
 
From what I understand and what I've read, too little grease and the hubs get hot from metal on metal friction but too much grease can also cause the hubs to get hot.

I regear'ed in 2018 and rebuilt my axles while I was in there. I followed @Tools R Us recommendation of don't over do the grease and tighten the nuts to 25 ft/lbs, spin, tighten to 25ft/lbs, spin, tighten to 25ft/lbs and Done. After the rebuild and on my first short test drive my hubs were cold which is good. My second drive was much longer and I was scared to touch the hubs out of fear of burning my hand and having to redo the work. I carefully grabbed each hub and found them only slightly warmer than ambient (80 to 90*). I have checked them a few times since after long trips and they have never been hot.
 
From what I understand and what I've read, too little grease and the hubs get hot from metal on metal friction but too much grease can also cause the hubs to get hot.

I regear'ed in 2018 and rebuilt my axles while I was in there. I followed @Tools R Us recommendation of don't over do the grease and tighten the nuts to 25 ft/lbs, spin, tighten to 25ft/lbs, spin, tighten to 25ft/lbs and Done. After the rebuild and on my first short test drive my hubs were cold which is good. My second drive was much longer and I was scared to touch the hubs out of fear of burning my hand and having to redo the work. I carefully grabbed each hub and found them only slightly warmer than ambient (80 to 90*). I have checked them a few times since after long trips and they have never been hot.

Back when I used to drive Land Rovers, I remember someone saying that too much grease actually insulates the hubs and traps in heat. So pack the bearings! Not the hubs.

EDIT: You want some grease in the hub cavity, but be reasonable. No need to put an entire tub in there.
 
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Back when I used to drive Land Rovers, I remember someone saying that too much grease actually insulates the hubs and traps in heat. So pack the bearings! Not the hubs.
That's not a correct statement.

You need to pack the area between the bearings because as the bearings heat up, they liquify the grease.

When you stop, the grease runs to the bottom and will find equilibrium and will fill the void in the middle, so now you have less grease in your bearings.

You need to pack the area between, but it doesn't have to be 100% full. Around 75% between the bearings is easily acceptable.

I read the amount in the FSM once, but I brushed past it and haven't looked again.

Better grease has higher meting points (called drop point) than some of the older wheel bearing greases. The older stuff would liquify quickly and it was more important to pack the void. The newer grease has higher drop points (I think nearing 500°F) so it stays where you put it more.

I use Lucas Red-N-Tacky 2 and have had excellent results. I have about 75K on my last repack. (I rebuilt it about 100K ago, but fought correct wheel bearing adjustment for 25K)
 
You need to pack the area between, but it doesn't have to be 100% full. Around 75% between the bearings is easily acceptable.
My bad, I didn't make myself clear. You want some grease in the hub, but not an entire tub's worth AFAIK. At some point it is too much. But you do need some grease in the hub. The Lucas Heavy Duty Green grease that I use drops around 500F too.

Just took the 80 for a drive. Higher speeds and minimal braking the drive flange was about 50F (my iPhone tells me its 45F this morning). Lower speed city driving and frequent braking brought the drive flange up to 70F. Both sides register the exact same temperature. Rear axle flanges (also have new bearings with similar mileage) were at 50F after my first run and were just above 55F after my city driving.

Given the distance from the rear braking surface to the hub and axle flange itself, this temperature makes sense to me for the rear.
As for the front, it's a much larger brake and is significantly closer to the hub. So I think this checks out too.

Going to keep checking temps for the next few drives just to make sure I didn't screw it up but for now I'm thinking it's all good.
(and to reiterate for future people reading this thread, I am checking drive flange temps to check if I made the bearings too tight. If they were too tight, the would get hot)
 

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