Wheel Bearing Temp Question

[rfloyd99]

The axles were recently replaced on my 27' TT, and the tech said the bearings looked fine. I have put almost 20K miles on this since I bought it new 3.5 years ago. I have had the bearings checked twice in that time, and they "looked fine" both times. They have grease fittings, BTW, but I have never added grease.

About a year ago I asked about bearing mntnce on this forum, and the answers ranged from repack every year, every two years, never (just shoot some grease into them from time to time).

Since we are leaving on a 7K mile trip soon, I want to do the right thing.

The last time I used the trailer, I drove 150 mostly highway miles, and 15 minutes after stopping I checked the temperature of each wheel with an infrared sensor. The last 10 miles had been city driving, so the brakes could have contributed to the heat. It was about 82 degrees at the time.

I have no idea if the temps I read are appropriate. I aimed the sensor at the alloy wheel, right at the hub. The readings were:

Right Rear 95 degrees
" Front 114

Left Rear 132
" Front 89

Does this seem normal? should there have been such a range, fr/back, L/R? If so, I will shoot some grease in them and call it good, unless you recommend something further is needed.

Thanks for your help!

[Slownsy]

The bearing temperatures are all over the place and not hot on same side so not sun, maybe bad adjustment maybe not taken in exactly same position. What ever you do don’t shoot some grease in the grease fittings or you are very likely to end op with it all over the brakes (yes I know all about spinning the wheel, it still happens to often) leave alone or dismantle and do it properly. Good luck
Frank

[dougrainer]

Whenever you install new hubs or new bearings and races into an old hub, you should pre-load the bearings. Pre-loading the bearings assures that the races in the hubs are 100% in place against their machined stop points and keeps the hub from wobbling after a few miles.

To pre-load the bearings, install the spindle washer and spindle nut onto the spindle with the hub and bearings in place.

Tighten the spindle nut finger tight (until snug) and then with channel-lock pliers or a crescent wrench, tighten the spindle nut another 1/4 turn or about 15 to 20 ft pounds of torque.

Now turn the hub ten revolutions. This will fully seat the races.
Now loosen the spindle nut very loose, then re-snug to finger tight, and engage the nut retaining device (some reverse lubricating spindles use a tab washer for the retaining device).

[Dave_H_M]

Lynnmor wrote:

Dave H M wrote:
:h Lynmore, where are those bearings on the Z? Deck spindles maybe?

The front axle pivots on those bearings. Most Z's have no pivot.

:S Got it. That is one I wish I had.

[Lynnmor]

shum02 wrote:
Don't worry to much about the source of the bearing, it really is the install that will make the difference.

I thought the same thing till I had immediate failures from improperly manufactured bearings from that country famous for junk. Yes, I believe most failures are the result of sloppy work, even some YouTube videos show slobs.

[Lynnmor]

Dave H M wrote:
:h Lynmore, where are those bearings on the Z? Deck spindles maybe?

The front axle pivots on those bearings. Most Z's have no pivot.

[RCMAN46]

With an infrared gun you should be able to shoot the drums after a high speed brake event and compare. If one is significantly higher temperature than the others a brake adjustment may be in order.

I am retired so every long trip I do I allow at least one extra day for the trip.

I start my long trips with about a 25 mile run using the brakes as little as possible. At the end of the 25 miles I do two things.

First check that tire pressures on my TPMS are balanced. Every axle should have the same pressure assuming the pressures were balanced when tires were cold and no sun exposure.

Second after coasting to a stop with little to no braking I check the bearing hub temperatures. Be sure to have any decorative covers removed. If I find a hub temperature much higher than the others I return home and repack the bearings along with a very careful inspection of the bearings and brake assemblies.

If you can not afford the extra day for a long trip I suggest taking the trailer out for a 50 mile run the week-end before a long trip.

[Dave_H_M]

:h Lynmore, where are those bearings on the Z? Deck spindles maybe?

My Toro Z is just coming up on its 20 yr birthday and I have never paid any attention to the two front wheels except hit the grease zerk once a year.

The deck spindles I grease every 8 hours.

[shum02]

Lynnmor wrote:
I just bought a new zero turn mower that has the same bearings as a typical travel trailer. It took 95 ft. lbs. of torque to loosen the nut. About four of the rollers actually had grease on them. So much for having professional mechanics do the work when even the factory has no clue.

It is so sad but true.

I've done mine for years, not that hard but yea, you can get your hands dirty but you can also use a bearing packer and avoid that.

I find with mine that they are about 10C above ambient when I shoot them with the temp gun. They should all be pretty close to each other but yes those in the sun will be a little warmer than those in the shade. If you can't hold your hand to the hub you're in the you need to do them now zone!

Lots of video's on youtube on how to R&R them. You WILL undoubtedly do a better job than any shop you pay to do it. A well packed/installed chinesium bearing set is way better than a domestically manufactured set that has been improperly installed and poorly packed. Don't worry to much about the source of the bearing, it really is the install that will make the difference.

[Lynnmor]

I just bought a new zero turn mower that has the same bearings as a typical travel trailer. It took 95 ft. lbs. of torque to loosen the nut. About four of the rollers actually had grease on them. So much for having professional mechanics do the work when even the factory has no clue.

[myredracer]

Our dealer removed and reinstalled our drums for a brake & bearing inspection at our request. Away on a road trip, I found one of the drums was quite a bit hotter than the other using an IR gun. When I removed the drums myself at home, I discovered I needed a wrench to undo the castle nuts and because they way over-tightened. They were also supposed to cleaned and repacked the bearings but I found 2 colors of grease inside so all they had done was pump more grease in via the zerks. Just can't trust a dealer to do anything right. :M

I decided to replace the original Chinese bearings with Timkens and no issues after several years. You'll know pretty quick when you go to remove the castle nuts if they were installed correctly or not.

Note that the drums can seem hotter on one side if travelling down a road with the sun hitting them and the other side being in the shade.

[beemerphile1]

I remove the decorative caps so I can touch the hub. If it burns - it is too hot and problematic.

[bartlettj]

The way to check your bearings temperature accurately is to drive for a while at speed and then coast to a stop. Brake use will significantly heat up the hubs. I think you need to adjust your brakes- tighten the cool ones and loosen the hot ones to they are more balanced.

[fj12ryder]

"About time you get your hands dirty and DIY."

Nonsense, some people have no desire to "get your hands dirty" as you put it. That's why they have shop or a mechanic take care of it. Perhaps they've tried it before and decided they didn't like it and didn't want to do it. Not your concern as that isn't what he wanted to know anyway.

I notice the higher temperatures are both on the same side, maybe sun shining, which will definitely raise tire temps not sure about wheel bearing. Also could be the crown of the road was loading one side of the trailer more than the other.

You say recently, but recently can be anywhere from 6 weeks to 6 months to a year. If you don't wish to do it yourself, have your shop/mechanic check the bearing freeplay. If he says it is okay, then carry your temp gun and check the wheels periodically while on the road.

[azdryheat]

If your bearings are properly adjusted they will last a long time and without heat issues. Bearings get hot when they are too tight. Sounds like you rely on other people to maintain your trailer. About time you get your hands dirty and DIY.

I will tighten the castle nut with a wrench to ensure the bearings are seated then back off the nut. I will next hand tighten the nut then back it off just enuf to install the cotter pin. There is a very slight amount of play in my bearings when I do it this way but it works for me and there is no heat buildup as a result. I've pulled this trailer all over the country for the past five years and my wheels are always cool or slightly warm to the touch depending on brake use. BTW, I've only repacked the bearings once and I don't shoot grease into the axle.