I would look for a new trans man you should not be having these problems only towing 12k, hell I pulled a 16k 5th wheel all over including the mountains and never took it out of OD and never had a problem. I have old customers that pulled 20K plus all the time and had 200k on the stock unit.
70 duster full chassis super pro 416 CNC Indybrock heads 727 w/brake
best so far 1.212 60 6.219 in 1/8 at 110.88 9.768 at 137.81 1/4
