Thanks for the advise on speed. I am really surprised to hear about the Tundra TX- I though it was bullet proof like the rest of Toyota! I had planned to go 60-65 mph but keeping up with traffic has always worked for me. DW will be happier below 70!! The truck has only 7K miles on it so maybe I didn't harm it. The tire limits are something I'll respect for sure!! Thanks again I'm never to old to learn (78).