when really to change tranny oil?

[greatwhiteZ28]

well im getting the stall+shift kit real soon and car has about 37,000 miles on and never been changed, the manual says every 30K or 50 K soo just want to know if its time

[camarolvr69]

Change it when you do the stall.

[Pro Built Automatics]

Having been doing this for about 30 years, I have found that you should monitor the fluid. Check it after doing anything unusual. If the fluid looks and smells ok, leave it alone. But at the first sign of it starting to smell or look burnt, do a "complete" change of oil. Changing transmission oil that looks and smells ok, is just a waste of your dollars.

[greatwhiteZ28]

now since you been doing this for a whilehave another question

i drive a flat bed chevy 5500 truck and has 140 K on it, is it time for a change? its deisel

[SteveC]

If the tranny fluid is "cherry red" and doesn't have a "burnt" oder, you are just fine.

If the fluid is "Orange" or "Brown" you need to change it.

SteveC