hub temperature

Discussion in 'Differential & Driveline' started by Sublime, May 17, 2017.

  1. Sublime

    Sublime Full Access Member

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    I have an odd question. Has anyone ever read their hubs temperature? I aimed my IR thermometer where you turn them to "free or lock" (warn) and an getting a reading of 145 degrees. Air temp was 80 degrees with normal driving, some stop and starts - no highway driving - about an hours drive.
    maybe its me but that seems hot., thoughts?
     
  2. Camar068

    Camar068 Supporting Member Supporting Member

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    I've often touched mine looking for results of bad bearings with no luck of heat at all. Not sure if that's a good test, but it makes sense to me. Mine are always roughly the same temp as say the outer rim or fender.
     
  3. Sublime

    Sublime Full Access Member

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    Sublime

    Thanks camaro68, im going to pull the bearings, repack them and tetorque them. Im betting they are to tight
     
  4. chengny

    chengny Full Access Member

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    No - don't loosen the bearings. It's never a bad thing to renew the grease. But when you reinstall them, bring the torque right back to where it was.

    First off a bearing running at 145 F is not considered hot at all. The general rule of thumb for power plant personnel is - if you can keep your hand on a bearing housing (or the hub in your case) for 10 seconds or longer, it is fine.

    Second and maybe more important is the proximity of the hub to the brake disc. When everything made up, they are clamped together to form one combined part (the hub and disc assembly - #57).

    [​IMG]

    Most of the heat generated by braking in stop & go traffic is absorbed by the brake disc.

    with normal driving, some stop and starts - no highway driving - about an hours drive.

    And since the hub/disc flanges are close coupled, a good percentage of that heat will radiate to the bearing housing section of the hub.

    Generally speaking, more bearings are damaged by not being tight enough - rather than being too tight.

    Just my thoughts.
     
  5. Sublime

    Sublime Full Access Member

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    Thats good info. , thank you
     
  6. Larry in WNY

    Larry in WNY Junior Member

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    I had a caliper not releasing enough and did as you did checking the rotor temp with IR thermometer. Temp was 145 to 168 on suspect wheel and 110 on the other 3. Told me there was a braking problem. Changing the caliper fixed it. Can't hurt to repack the bearings Also check for brake pad wear and different wear pattern on the rotor.
    Larry
     
  7. Sublime

    Sublime Full Access Member

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    Update in case anyone wants to know. I ended up removing the left rotor and bearings. They looked good, repacked them installed a new seal. torqued the first nut to 50flbs backed it off and torqued to 35ftlbs. This time I backed it off until there was very, very little play in the bearings, installed the lock washer and torqued the locking nut to 50ftlbs. Buttoned everything else up and went for a half hour ride. the temp of both hubs were still 140 degrees. keep in mind that I did not loosed the right side and I know the bearings on this side are tighter so that made me think its not the bearings. Lifted the front end and spun the wheels by had, both spun two revolutions with little drag so that cleared my mind of a stuck caliper (at least free wheeling).
    What I should of mentioned in my original post was replaced just about everything on/in the front axle last winner including the brakes/rotors. I do not drive it on salt cover roads and had only put a thousand miles on it since December. I did some more reading about the brakes and remembered I never seated or "bed in" the brakes! aaahhh. so back out and did ten 60mph to 10mph stops. drove another few miles to cool off the brakes. next day took a long drive and check the hub temp - 95 degrees. IT SUXS when you memory slips :(
     

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