Nissan Repair: Transmission, remanufactured clutches, borg warner parts

Question
Why does my 1990 nissan keep blowing out automatic transmissionns. I'll be driveing down the hwy. doing around 60 mph. It will kick out of overdrive and go and lock in to3rd gear with no reverse. Thats 2 transmissions thats done the same thing. what do you recomend, and where should I get a transmission worked on at. Thanks Stranded

Answer
Bruce,

The transmission protects itself by locking into second gear to protect its internals when it discovers a problem.  I would say Cottman Transmissions since that is where I have had good luck with national transmission chains.  The other guys have not been as good to me on transmissions.  Second, I would make sure the transmission lines and cooler are flushed as part of getting a transmission installed.  Lastly, I would install a Hayden 404 cooler installed, in line, with the factory cooler in the radiator.  I use this comination with success getting transmission fulid temperatures down over fifty degrees.  Heat kills automatic transmissions and if the guys that built the transmission did flush the cooling lines I would almost bet the cooler in the radiator is not up to the task of keeping your transmission cool enough.  Also, when you get your transmission rebuilt have them use new clutches and bands and friction surfaces along with a new pump.  I like Borg Warner parts and they do cost more but are worth it in the end.  Many shops use remanufactured clutches and bands and these wear out faster than new ones.