I was able to downshift into 1st while moving less than 5mph.
Do I contribute this to the heat or do I have another issue?
Personally I do not think you have an issue at all here.. Granted I am sure your tranny is older and worn some, but this was the norm back when these were fairly new...
Why would you want a first gear downshift for anything but coming to a stop at a sign or redlight to be prepared ( in first gear) for proceeding after stopping????
Again, I don't remember 4 speeds being really friendly about going into first at much speed....
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