Truck has 108,000 actual miles , looks like no work done to the tranny , just bought this vehicle. Driving away not a problem until I was started down a hill and when I was on a flat part of the road I was trying to accelerate while in Drive but the vehicle was not responding , so I slowed down quite a bit and moved into 2nd gear and it felt good there with proper response to the accelerator pedal. Once down off the hill and into the town, I was able to drive normally in the 3rd gear/Drive but once in a while it would start to slip again. Decided to leave the vehicle with the previous owner for a few days and took it over to a local tranny shop, they did a diagnostic on this TH400 tranny and told me that the tranny was pressurized as part of the test, it was throwing tranny fluid out of the vent tube during this test of which they indicated that this was due to seals that had become hard and there was no way to know what the extent of damage might be inside the tranny until it is opened up. What should be a reasonable price to rebuild this TH400 at a national tranny shop ? Would I be better off to use a national tranny rebuild shop or go to a local shop ? What say you ??? I am located in South Central New Mexico ..................... Thank you