opinions ---hub temps

jlh3rd

Chief Petty Officer
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Jul 10, 2017
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2007 karavan twin axle pontoon trailer. Factory setup for the 24' '07 pontoon boat I've owned for about 4 years now.
wheels/tires are the 10", hubs are 7" with electric brakes added last year. Straight spindle, front/ rear bearings are same size (44349's).....
Always maintained, grease always added if towing any long distance. Yep, I bring the grease gun with me. Axles are Karavan easy lube.....The rear axle was replaced a few years ago with an exact, new Karavan axle....

So, coming back yesterday , 200 miles, outside temp was around mid 90's, got home and checked temps.....
The right front and rear hubs were showing 148 degrees...the left rear was around 127...and the left front was 109 ( which would be normal in my opinion)...
The tires were all normal temps and about the same, none over 110.....90 psi +/-
I have no noticeable towing issues.....actually, my '08 silverado , 5.3, averaged about 12 mpg.....
.....so..any observations?....
 
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airshot

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Jul 22, 2008
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Besides adding grease, when have you actually pulled the bearings, checked them and hand packed before reinstalling?? Both outter and inner!! This should be done every 3 years even with hub grease ports!! You might have some bearings that need replaced....
 

Sprig

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May 2, 2016
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I agree with the above, when is the last time you pull, inspected, cleaned and repacked the bearings.
One thing that’s obvious but people often don’t think about, were the hubs that were running at 148 on the side that the sun was shining on. You would expect the hubs on the side the sun is shining to be hotter than the other side.
 

harringtondav

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May 26, 2018
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Temp sounds a bit high. I use my hand to check and it is never uncomfortable. Good guess would be 100-120 degrees max.
Once you check your bearing condition be mindful of proper wheel bearing tightening process. Yours sound over tightened.
Remembering from my long retired FWD cars and manuals, the process is to assemble the hub/wheel assembly onto the spindle, finger tighten the castle nut while rotating the wheel. Then apply a low amount of torque...10-20 inch/lb IIRC...while rotating the wheel (not much by feel). Then touching only the castle nut, back it off and re tighten to finger tight. Install lock cap and insert the cotter key. If things don't line up rotate the nut CW just enough to get the key through.
 

RMClark

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Jul 19, 2020
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94
I use touch; I feel the hubs for temp when I make a stop or get to the lake.

Normally, I expect the hubs to be comfortably warm, not hot, when I touch them. Last week, I took the boat out and when I got to the lake (48 miles away), the left hub was normal, but the right hub was about as the hot water coming out of the tap, and that's set to 120 degrees. When I got home, I pulled the hub and repacked the bearing. I'm going back out tomorrow, so I'll check it again.

I repack the bearings every year before the start of the season. It's part of my annual boat prep.
 

briangcc

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Jul 10, 2012
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2,360
Mine are usually luke warm at best. Any warmer and there's generally an issue.
 

roscoe

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Oct 30, 2002
Messages
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Always maintained, grease always added if towing any long distance.
Shouldn't be necessary unless grease is leaking out.

You know you are supposed to jack the trailer up and spin the wheel when adding grease to those hubs, right?
 

jlh3rd

Chief Petty Officer
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Jul 10, 2017
Messages
559
Besides adding grease, when have you actually pulled the bearings, checked them and hand packed before reinstalling?? Both outter and inner!! This should be done every 3 years even with hub grease ports!! You might have some bearings that need replaced....
no, I have not repacked them in over 3 years. I've only towed this distance now, and a once a year 200 mile round trip the past 4 years......
they are timken bearings...not chinese...
I will repack before next year ...
thanks..
 

jlh3rd

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Jul 10, 2017
Messages
559
I agree with the above, when is the last time you pull, inspected, cleaned and repacked the bearings.
One thing that’s obvious but people often don’t think about, were the hubs that were running at 148 on the side that the sun was shining on. You would expect the hubs on the side the sun is shining to be hotter than the other side.
the right side was more into the sun....the temp. gun's accuracy may be off, I just use it for a reference and to help spot possible issues...it didn't burn my hand but I didn't want to keep my fingers on the hotter ones....
thanks..
 

jlh3rd

Chief Petty Officer
Joined
Jul 10, 2017
Messages
559
Temp sounds a bit high. I use my hand to check and it is never uncomfortable. Good guess would be 100-120 degrees max.
Once you check your bearing condition be mindful of proper wheel bearing tightening process. Yours sound over tightened.
Remembering from my long retired FWD cars and manuals, the process is to assemble the hub/wheel assembly onto the spindle, finger tighten the castle nut while rotating the wheel. Then apply a low amount of torque...10-20 inch/lb IIRC...while rotating the wheel (not much by feel). Then touching only the castle nut, back it off and re tighten to finger tight. Install lock cap and insert the cotter key. If things don't line up rotate the nut CW just enough to get the key through.
yep...I've repacked and pre-loaded bearings for decades...pretty much use the same procedure......
thanks
 

jlh3rd

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Joined
Jul 10, 2017
Messages
559
Shouldn't be necessary unless grease is leaking out.

You know you are supposed to jack the trailer up and spin the wheel when adding grease to those hubs, right?
no..never heard or read that anywhere.....so, I'll probably add that to my procedures......
thanks
 

dingbat

Supreme Mariner
Joined
Nov 20, 2001
Messages
16,074
they are timken bearings...not chinese
Don’t assume…Timken manufactures in 33 different countries, China included.

If the bearing doesn’t have USA stamped on the race, it’s not.

14C9BAC1-21F6-48DC-962F-AFA66ED4E197.png
 

badrano

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Aug 7, 2018
Messages
343
Are there brakes on the trailer? If you have disc brakes, it's possible the calipers are sticking.
I just completed a 300 mile run....on the way to, hubs were running upper 110's with mid 80's air temp....on the way back, hubs were running lower-mid 120's with mid 90's air temp.
To date, the only time I had hubs at 148 or higher was due to sticking calipers.
 

roscoe

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Oct 30, 2002
Messages
21,739
no..never heard or read that anywhere.....so, I'll probably add that to my procedures......
thanks
Its in the trailer manual, if you have it.
Also covered in this video at about the 15 second mark.


I doubt this has anything to do with your heat issue, but thought I'd pass it on.
 
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jlh3rd

Chief Petty Officer
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Jul 10, 2017
Messages
559
Are there brakes on the trailer? If you have disc brakes, it's possible the calipers are sticking.
I just completed a 300 mile run....on the way to, hubs were running upper 110's with mid 80's air temp....on the way back, hubs were running lower-mid 120's with mid 90's air temp.
To date, the only time I had hubs at 148 or higher was due to sticking calipers.
electric brakes...added last year....
 
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