Wheel bearings

JJBIRISH wrote:
Heat is heat and the bearing temps will rise and fall from all of those reasons and unless you know the normal and acceptable temp range, and weather the measured temp is a fluctuation or constant temp, you just can’t make those claims…
Even the normal operating temp change with bearing size, load, speed, type of lubricants, and proper preload… I would think this is how they determine what bearing to use in mfg.…

I believe careful monitoring and observation of applications can sometimes reveal early warning signs of clearance and endplay-related problems, and is a good way to intervene before a permanent failure occurs… I don’t believe a temporary elevated temp is proof that a permanent or catastrophic failure has already occurred…

The big question remains what temp is too high and how accurate can we be at measuring it…
Even inaccurate but consistent measurements and help diagnose a problem…
A safe operating temp can be vastly different for the exact same bearing with different types of lubricants…

There isn't a set temperature that can be regarded as too high or even one that can be regarded as normal. The amount of heat generated by a properly running bearing is very small compared to that generated by the brakes and tires. It is not bearing temperatures that require the use of high temperature lubricants.

As stated, the real value of checking temperatures is to find a large difference between one wheel and the others, which would indicate a problem. The problem could be a dragging brake, under inflated tire, suspension problem, or a bearing.

All I am saying if that if you find an appreciable temperature difference and the cause is a bearing, that bearing is already toast, because that is why it is hot. Checking temperatures is no substitute for regular servicing unless you like to run things until they fail.