hub temps

[lovetoski]

Hi all,

In a post a few days ago regarding wheel bearings, IdahoDoug mentioned checking his hub temps by hand-touch on long trips. This got me thinking...I use an IR thermometer to measure the temp of my ski wax iron (here's the link, as it's a cool tool http://www.tognar.com/wax_tools_hot_irons_corks_brushes_ski_snowboard.html#GPM-3100).

Since I had a 600 mile trip yesterday, I brought the IR thermometer along with me. I measured my hub temps at a couple of stops, and the highest temps I got were as follows:
Drivers Front - 117F
Pass Front - 113
Drivers Rear - 125
Pass Rear - 108

The driving conditions were - Ambient 85F, cruising at 80mph, 5 adults + 200 lbs of gear.

Any thoughts on the relavance of this method, and the resulting values?

Note to those married guys - my wife really thought I'd gone off the deep end by doing this! She liked it a little better when I explained why this might be important. Just beware...

BTW - After returning home it occured to me that I could use this to measure temp variation across the tire also, unfortunatly this was after the car was sitting for awhile. I checked anyway, and they ranged from 82 - 89, with no tire having more that 2 degree difference between sides.

 

[LandCruiserPhil]

Doug what size and make are the tires you are running?
Do you know the weight of your Cruiser?

Thanks Phil

 

[lovetoski]

They are Open Country, Radial LTX (private label Michelin knockoffs I suppose), sized 265/70X16. I've never weighed my cruiser, but I assume it's the stock weight (whatever that is.) I've added mostly lightweight things - rack & second battery.

 

[Doc]

No input on your post, but those IR thermometers are really nice for dialing in camber settings for auto-x!

Ok, some input. Those values aren't really that different from one another. Not so much that I'd worry about it anyway.

 

[Scamper]

Nothing is varying by more than 10% over ambient...doesn't look troubling to me.

Then again, don't know what they should be running; just know that they will run a bit over ambient.

Gotta take into consideration that ID has been doing this for some time and has The Force workiing for him on this...i.e., from his experience, he knows what's okay and what's not.

 

[Safado]

LoveToSki...ever try that thing on a kid? Seems like a lot less intrusive than some of the other methods out there.

Funny you mention this test though...I was doing this the other other day via the force and found some differing results. I had just repacked the rear hubs and wanted to feel if I had screwed anything up. The front hubs were always hotter than the rear....too hot I believe.

After a 15 mile round trip on the freeway:

The fronts were too hot to hold for more that 2 seconds...the rears could be heald for around 9.

After a 50 mile trip on the freeway

Results were the same.

37 BFG ATs on 17inch steal rims....there's a balancing issue with them as well that needs to be fixed.

Where's IDAHODOUG (yoda) when you need him?

 

[scottm]

Prolly out on his boat, it is a weekend I've been checking my hubs at gas stops on the highway for years, and I work 180 miles from home. Never felt anything above warm on any hub. I've checked on my wife's 80 a few times, same. Haven't checked since I did my wife's birfs, hopefully the same.

 

[landtoy80]

To check your hubs you need to NOT use the brakes.
When you use the brakes, the rotor and hub will get hot.
I think what you were measuring from one hub to the other was the condition of your brakes.

A way to test is to drive at hwy speeds. Find an off ramp that goes up hill. Use the parking brake to stop. Then check the temp.
I bet you get different resuls with using the p-brake and foot brakes.

 

[ginericLC]

You rears could still heat up using the parking brake.

Very interesting I'm going to have to try that sometime. I'm constantly touching my hubs to check the temp. I was nervous after touching them the other day so I ripped them all apart. I could find nothing wrong with the new grease or bearing adjustment. I'm getting good at it though. Less than 45 minutes to disassemble both front hubs and button them back up. My nervousness turned out to just be a hot day with some braking. It was over 100 degrees outside. Even my fenders felt hot to the touch.

 

[lovetoski]

Safado - knock on wood, but my kids haven't run a temp since I've had the IR thermometer! I've thought the same though, and am sure I'll get a chance to try it. I'm not sure it's as accurate as one designed for a human.

All - I wondered about the brakes too. Good suggestion to find an off-ramp where I could coast to a stop.

Besides the hub and tire temps, you could use this to measure temps nearly anywhere. The only wierd factor is that the "emissivity" is different for different materials. If the emissivity is enough different, you have to change the calibration of the thermometer. For dark objects, you don't have to worry, the default setting is OK. For shiney materials, you must make a change to get an accurate reading. That said, it's still a really easy way to measure the temp of most anything.

My problem is that while I can take the temp, I don't know what it means!

Best Regards,

 

[IdahoDoug]

Ah, back from a day on the boat as speculated. Released a wild turtle we found last weekend and kept for a week in a secluded bay we frequent. Watched a humming bird of all things harass a large hawk perched in a tree above us, read several books to the kids and they got to try out their new folding pullman-style bunks I've got about 30 hours into building. We took a group nap during the hottest part of the day. Nothing like Yanni quietly on the CD, the hum of a fan, the sound of water lapping on the hull and a pair of little snugglers to make the world seem to be the most perfect place ever created. Sigh.

My wheels are routinely too hot to touch for long on highway drives and it's due to the exit ramp braking and resultant heat soak into the aluminum rims. The fronts are always hotter. I've been doing this for so long though that patterns emerge. If you have a brake caliper hanging or a wheel bearing or hub lube issue you'll still note a difference. In other words, though they're all hot, if there's a problem that wheel will be HOT, as in holy s*** that things really really hot. Minor variances are no problem. To fog things up a bit, I've noted on my trailer that sometimes a wheel that's hot on one gas stop will not be the hot wheel on the next stop. Figure that out. Trailer brakes blow. This has never been the case on a car I've owned - just trailers.

The uphill ramp is a good call, by helping to eliminate heat differences due to braking. That's a good thing if you can pull it off, but be advised the parking brake strategy would simply leave you with very hot rear wheels and whatever the fronts were running at with no brake induced heat. Stopping a car from X speed generates Y heat whether you put the Y into all 4 wheels or just the 2 rears. Also, an IR gun - won't it pick up the radiant heat from the scorching discs as well? The heat's simply flooding out of the wheel openings and engulfing the whole wheel. It may be that physically touching the wheel immediately upon stopping at the exit ramp is a more accurate picture as it reveals the wheel temp before the heat soak brings the wheel temps up. This doesn't take long with aluminum, BTW.

DougM

 

[scottm]

Another "too hot to touch"? Odd that mine are always just warm even when I was hauling a construction trailer every day. It was a new trailer, used daily, and I always set the brake controller a bit heavy, so easy on my brakes. I always brake as efficiently as possible, a habit from landing airplanes I guess. There have been episodes of aggressive braking on exit ramps, and still no hot hubs.

Many airliners have brake temp guages, kind of useful, I'm not sure how they read temp. We recently had an airliner blow several tires after a lot of taxiing and two runs up to less than 80 knots with minimal braking. One of my (other) brothers works on Bluebird Wanderlodges, says the tires are always too hot to touch after running on the highway.

 

[landtoy80]

<You rears could still heat up using the parking brake.>

Back off one p-brake so only one will work. {do I have to think of everything???}

scottm> I finally saw you going S on 31 just south of Holland.I didn't know you had 20" wheels, no lift, tail light guards and other fancy road cruiser extras

 

[Tooth Fairy]

I just did the whole front axle service on an LX450 and after driving 30 miles on the hiway at 75mph and stopping the the hubs were too hot to hold onto. Not too hot to touch. I got it home and backed them off and rechecked them. I didn't have a chance to run it at hiway speeds.

Is this right? :

Torque hubs to 43lb/ft turn 5 times each direction then back off the nut and retorque to 43 lb/ft.

I checked resistance by hooking the fish scale to the fins in the rotor and the wheel studs.

I had resistance of 8lbs on the fin and around 12lbs on the rotor.

I've always done it by feel in the past and never had any problems.

 

[PHAEDRUS]

back off and retorque to 48 in/lbs IIRC.
Dave

 

[landtoy80]

I have noticed they when you torque the lock nut to 47ft/lbs that the adjusting nut turns a little bit. The lock warsher is there to keep the adjusting nut from turning when torqueing the lock nut.
But when you get to 47ft/bls, the adjusting nut turns a little bit. If you take a hammer and a screwdriver, you can move the adjusting nut back. The lock nut and the lock washer will move too.

The little notch on the warsher keeps the nuts from turning. But there is a little play with the locking warsher and spindle.

What I did this time was too back off the adjusting nut and checked the resistance. I don't know if it makes any difference but I am sure that over some time the nut and washer will move to this position .
When I adjusted the wheel bearings last time, I had about 6 lbs on the scale. When the nuts moved back maybe it moved enough to have loose wheel bearings.

 

[RavenTai]

preload si suppose to be checked at the wheel stud, 12lbs there is at the top of the range, it is 43 foot pounds to seat the bearings and then 48 Inch pounds to start the preload and then adjust from there

5. ADJUST PRELOAD
(a) Using SST, torque the adjusting nut.
Torque: 59 N·m (600 kgf·cm, 43 ft·lbf)
(b) Turn the hub right and left 2 or 3 times.
(c) Using SST, torque the adjusting nut.
Torque: 59 N·m (600 kgf·cm, 43 ft·lbf)
(d) Loosen the nut until it can be turned by hand.
(e) Using SST, torque the adjusting nut again.
Torque: 5.4 N·m (55 kgf·cm, 48 in.·lbf)
NOTICE:
Check that the bearing has no play.
(f) Using a spring tension gauge, measure the preload.
Preload (at starting):
28–56 N (2.9–5.7 kgf, 6.4–12.6 lbf)

 

[landtoy80]

What do you torque the lock nut too?
THe FSM says 47ft/lbs.

Is that info in your FSM or did you add the 48 in/lbs?
My FSM says back off the adjusting nut and check the preload.

 

[RavenTai]

that is strait from the 96 FSM for the fronts no addition from me, the rear says to torque it back it off hand tight and tighten it until the preload is hit

the torque for the lock nut is 47 foot lbs, mine did the same, after installing the lock nut the preload went up I think part of it is the play in the threads of the adjusting nut, when alone it is pressed to the outside by the bearing, when you add the lock nut it is moved inboard face of the threads, changing the preload, IIRC the diffrence was about 1 flat

 

[landtoy80]

think the 94 manual need to be rewriten and my FSM should be replaced, all 5 parts of it