When should I change my transmission fluid on my first Gen?

I have 146,000 miles on the truck. 2nd Owner. Bought the truck with 104,000. AAA suggests a tranny fluid exchange. 12 quarts. When and how often should I change the tranny fluid? The truck is an automatic. Why do forums say to not flush? What should I use and how much of it? Truck runs like a freaking champ by the way.

 

IIRC Toyota recommends every 60k, but most dealers will recommend it every 30k. I personally shoot for 50-60k

 

Changed mine as soon as I got my truck; just thought it was normal to replace all the fluids on any used vehicle you buy.

Check the color and consistency via the dipstick.

Do not bother with taking it to a shop for a "power flush" or anything if you do decide to replace the fluid; do it yourself.

Either 1. Remove drain plug, drain, reinstall plug, and top off at the filler neck (3-4 quarts)

or 2. Drop the pan, replace the filter and gasket, reinstall, reinstall plug, and refill at the filler neck (4-5 quarts)

 

to answer your question... the flushing or not flushing an auto transmission is a long time debate. The pros are that it all of the fluid is replaced and the cons are that it can disturb dirt particulates and these little bits can cause the spool valves that make the trans shift to stick. If you are concerned and you know which end of a screwdriver to hold this is an easy driveway job, a bit messy, but easy, there are videos out there on what to do, what equipment to have, etc. etc.

 

Changed mine as soon as I got it. It looked dirty.
My neighbor and I just disconnected the two rubber lines to radiator. Point both into a bucket. Start truck for 30 seconds. Shut off.
Add the same amount that came out, through trans dipstick tube. Start truck for 30 seconds. Add same amount that came out.
Repeat till fluid is clean.
Reconnect both lines. Wait several hours for dipstick tube fluid to drain. Re check fluid level. Easy peasy, like Glamisman said.
The trans fluid is circulating, all your doing is replacing old with new. Not forcing any dirt loose. Just my opinion.

 

Make sure you use a GL4 fluid and not GL5 as most gear oils are.

In my experience first gens really REALLY like Redline MT90.

I change every 30k, sooner if I believe I may have gotten water in it from off-roading.

 

Factory manual says to check it every 30k or so, but there is no regular replacement interval.

 

Drop the tranny pan, clean it and the magnets, install a new filter, use Toyota FIPG. Install a tranny cooler after the radiator cooler. https://www.tacomaworld.com/threads/hayden-transmission-oil-cooler-install.108470/
Use Toyota tranny fluid.

 

Instead of aluminum bushings I used plastic bushings found at Home Depot. Been 2 years since I did that work, tranny shifts smooth and runs cooler.