Toyota Corolla transmission flush

I recently had a transmission flush done on my '05 Corolla (automatic with 45,000 miles on it) at the recommendation of an independent shop that said the fluid looked dark and dirty. The shop performed the flush but did not use Toyota Type T-IV fluid as is called for in the Toyota manual. The Corolla manual strongly warns of damage occuring from the use of any fluid other than Type T-IV. I’ve also discovered that Type T-IV fluid is naturally darker in color than regular fluid making me think the original fluid was not dirty and the independent shop was ignorant of this fact.

Should I ask for a refund since the shop did not follow the maufacturer’s recommendation? Should I perfrom another flush at Toyota so I can use their proprietary Type T-IV fluid? Will their be damage to my transmission as the manual warns if I leave the current fluid in there?

either ask for a refund or make them reflush using Type T-IV, at no cost to you, if you trust them to do the job correctly the second time. Mobil 3309 is the only other ATF I found that meets T IV specs. I didn’t search very long, but I recall there aren’t very many alternatives to the real Toyota stuff.

while you don’t have to go to a Toyota dealer, to get the flush done, make sure it is clear wherever you leave the car that you need T IV or Mobil 3309. In fact, any independent garage can do the reflush, so asking for a refund and immediately going somewhere else may be the better solution.

Do not leave the current fluid in there. By the way, what fluid did they say they used?

First, I found from experience that the Corolla transmission does need periodic fluid changes regardless of what the manual says. My daughter has an 03 Corolla and at 75k miles it was black.

However, I do not believe in flushing the transmission, just a drain and refill. A drain and refill only replaces about half your fluid though. The flush machines claim to do a 100% change but I don’t believe that because it is pouring fresh fluid into the pan where it mixes with the old fluid. If the shop dropped the pan, cleaned it and the filter, then refilled the pan with fresh fluid and then hooked up the flush machine, then they might get close to 100% of the old stuff out.

You do need to get the T-IV fluid into your transmission. I think this shop was in error to use anything else. Just about anyone who works as a mechanic knows that there are several car makes that use a specific fluid. Toyota, Honda and Chrysler all require special fluids. Dexron no longer works in these.

I assume they probably put Dexron III in your transmission, don’t let them sell you a bottle of magic potion that supposedly makes Dexron the same as T-IV. It drives me crazy when do-it-all shops put the wrong fluids in different cars, it happens ALL the time and probably the majority of drivers don’t even realize it. Find an independent shop that works on Toyota/Lexus cars only, or mostly…they are less likely to screw up on such a simple thing.

In the future just drain and refill the fluid. There is a drain plug on the bottom the the trans pan and no filter to change on your car. So just drain and refill at intervals suggested by your owners manual. It’s easier to do than an oil change! Just make sure you refill to the proper level.

Try getting your money back from the shop that screwed up and find a Toyota shop in your area. Don’t let that place touch your car again.

FYI, there is a filter. Its a fine stainless steel screen and it usually is not replaced, just cleaned. There is a drain plug, but you get an addition 0.6 qt of old fluid out if you drop the pan. The bottom of the pan has magnets in it to hold any suspended metal particles. By dropping the pan, you can clean a lot of gunk out of it, but you can probably get by with only dropping it every other drain and fill, jut use the plug the other times. 3.5 qts with the plug, 4.1 dropping the pan.

If you drop the pan, you must get the gasket from a Toyota Dealer, the ones from the parts houses do not fit, no matter what their catalogs say. The filters that come with those kits do not fit either.