Trailer hub temp question

figured you guys would know if anyone would.

I have one of those red dot temperature guns

when traveling, you pull in for a rest break, pull out your red dot temperature gun and check the trailer hubs.

question: what is an acceptable heat range for the hubs??????

I am assuming they all should be fairly close together in temp range.

thanks for your reply.

27 ft tow behind lite trailer. standard unit, 15" tires, 2 years old.

I use the IR temp probe all the time. Using the brakes will add temps so be careful when you take the temps. For most non braking temps I usually see 115 or so with a variation of plus or minus ten or fifteen degrees between the hubs. Obviously braking a lot and then taking the temps will raise those values. Long downhill mountain grades with lots of braking can increase temps very quickly.