I have a 99 f-250 superduty 4x4 w/7.3 liter deisel. I am the original owner and it has 140K miles on it. My problem is after about 15 minutes of driving the tranny starts slipping and when I come to a stop it will not down shift into 1st by its self I have to do it manually. It has no codes in the system, and the fuild and filter have been changed about 7,000 miles ago. I changed it again to see if it would fix it, but it made no differance. Could it be a dirty valve body? Please help! thanks Nick
P.S. This is my first time using this forum, How do I check the results?
P.S. This is my first time using this forum, How do I check the results?
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