I agree with you about the temp. You say it only happens once in a while. So was the temp taken after a trip with no panic stops? The no. 1 reason for high temp, at a one wheel only, is bearing. Of course, there are other reasons.
You could have constant "shoe drag" if it pulls to left while coasting straight.
In the old days we used to turn drums and arc shoes. So that we got even contact. Is there any way you can see if the shoe wear is odd?...if drum wear is odd.
160-180 degrees could be normal. Get the other side tighter/Get the temps near equal.
Check your other vehicles to see if front temps are near equal to each other.
All these suggestions/tests we are giving are to get some information, hopefully you will get ideas from the data.....and possibly find the cause.
