I have a 94 z with automatic transmission ( 140k miiles) and embarrassed to say have never had it serviced. I really never planned on keeping the car for so long. It seems to shift properly and with my limited knowledge of cars seems ok. I would like to get it serviced but have heard that service may be like opening a can of worms and problems may develop from service.

I also heard to stay away from the large chains like Aamco as they sometimes claim non existent problems costing hundreds or more in phanthom repairs. Can you steer me in the right direction?

Thanks for your opinions

 

A 'transmission flush' is generally what opens 'the can of worms'.
Something you can do yourself is filter and fluid change. Drop the pan(most of the time messy,get one corner to hang low to minimize mess) and try not to damage the gasket. Pull out filter and install new one. re-install pan-the 2 longer bolts are for the shifter linkage bracket. Add fluid and let run to find out how much more fluid has to be added.

 

Aamco I know uses only synthetic fluid so I would go to wallmart and get supertech automatic trans fluid for use in vehicles previously using dexron/mercon. 1 gallon.Then I would get a transmission filter(usually comes with gasket) then go to local trans shop and let them perform the service .They usually clean the pan and magnet.The trans holds about 9-11 quarts of fluid but you can only get about 4 quarts out at a time.I have heard of a machine that can suck out everything at one time,but I've also heard that it breaks a rubber seal inside the trans.Maybe a trans guy can chime in on this one.Hope this helps.