Opinions please

Spike · Posted: Sun Jul 12, 2015 2:27 pm Post subject: Opinions please

Would like to know peoples opinions on average hub temps while towing, both highway and stop and go. I have tandem axle with hydraulic disc brakes on oil bath hubs all four wheels. Getting a reading of about 10 degrees differance between high and low. Thanks all.

Sunbeam · Posted: Sun Jul 12, 2015 3:08 pm Post subject:

I have a 22 on a tandem axle trailer with bearing buddies. I dd put in new Timken bearings/Kodiak brakes etc. (never used it with the old stuff, so can't compare).

I'd say the bearings tend to run around 15º - 30º over ambient temp (so say, 95º on a 70º day or 110º if it's 95º outside). The variation between hubs might be around 5º or so. I am careful to tow with the trailer level since it is a tandem; measurements are made with an IR thermometer just after pulling in to a rest or fuel stop.

A note is that when I first had the work done on my trailer, there were (as it turned out) quite a few flaws in the work. I was getting really high bearing temps (180º - 200º +). Of course when I called the shop that had done the work they said that was normal and I was a worry-wart. As it turned out, the castle nuts were too tight, some of the brake shoes were dragging on the hub, one of them was crooked and half worn down, the brakes were sticking due to a kink in the line (that I had pointed out but they'd said not to meddle) etc. etc. Got all that straightened out (in the middle of Georgia, the middle of Montana, etc.) on my first cross-country trip, and right away the bearing temps went down to "nice and cool" and have stayed that way over many thousands of miles.

PS: I don't tend to tow "stop-and go," so can't speak to that specifically. OTOH, I might pull into a town and drive 2-3 miles through surface streets, and I haven't really noticed a big difference then after stopping.

T.R. Bauer · Posted: Sun Jul 12, 2015 4:57 pm Post subject:

I would not worry about a 10 degree difference myself as long as they are not cooking since bearings can operate in really hot conditions. As noted above, they will be a higher temperature than the outside air temperature. I have found that if everything is right, they are about the same temperature as the tire, in general, if not a bit cooler. I'm sure lots of folks will give you temperature readings as this thread progresses, however they don't mean a ton unless you know the outside temp as well......I wouldn't put a ton of thought into this unless you really have an issue with obvious signs of distress.

Wandering Sagebrush · Posted: Sun Jul 12, 2015 5:20 pm Post subject:

Chuck, that is roughly what we see.

TyBoo · Posted: Sun Jul 12, 2015 5:47 pm Post subject:

I think 10° over ambient is real good. Having all four of them very close to the same is the biggest test. If one is warmer it indicates something going on. If both on one side are warmer than the other side it could be the boat is off center on the bunks. If the front two are warmer than the two on the back axle it could be too much tongue weight or a low hitch, and vice versa for vice versa.

You did ask for opinions, and of course, that's all this is.

I worry too much (B~C Ken says I am trailerphobic), so I check my hub temps often - like every other freeway rest stop. It's been a while since I towed anywhere, but it seems the hubs were always 10° to 20° warmer than the air and within a couple degrees of each other every time.

localboy · Posted: Sun Jul 12, 2015 5:54 pm Post subject:

From an old thread before I re-packed all the hubs. Freeway towing, disc brakes.

Will-C · Posted: Mon Jul 13, 2015 12:34 pm Post subject: Opinions please

I don't have temps for you but I touch the hubs on about every stop with the two fingers that you would use to give a peace sign. Too hot to touch would indicate a problem for me. I lay my hand flat on the tires. Too hot to touch out comes the pressure gauge. Sometimes one side will be in the shade and the other in the sun and that can account for a difference in temperature.
D.D.

ssobol · Posted: Mon Jul 13, 2015 3:11 pm Post subject:

If I can't lay my hand on the tires or the hubs, something is wrong.

Jack in Alaska · Posted: Mon Jul 13, 2015 4:46 pm Post subject: temps

The IR measured bearing temps will be 10F over the ambient. The sunny side will be 10-12F hotter than the shady side.
Any bearing temp over 115F would worry me. Something is wrong and a problem long term.

Sunbeam · Posted: Mon Jul 13, 2015 7:39 pm Post subject: Re: temps

colbysmith · Posted: Tue Jul 14, 2015 12:07 am Post subject:

I also have Oil Bath bearing hubs. I can't remember the normal temps they run at, but they do run cooler than the greased hubs. I wouldn't worry too much about a 10 degree difference between hubs. It's more than likely a brake rubbing a bit more on the hotter one. I do know with the oil bath, I can touch them with my hand. (Even while towing out to Lake Powell last month! Smile

Colby