1996 Tacoma transmission fluid service

My 96 Tacoma is due for another transmission fluid and filter change per the manual. I took it to a MX shop and they tried to talk me out them doing it for liability reasons.

My truck has 190,000 miles on it and still runs like a champ, the tranny fluid is a little brown but not overly discolored.

Whats the story? Is this guy being overly careful?

 

I would flush it yourself, replace with maxlife synthetic, and not worry for another 60K miles. By flushing I mean using the tranny pump of course, not a flush machine. There are multiple write-ups on this forum. I use the pump 3 out, pump three in, repeated 4 or 5 times.