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Do I change the transmisison fluid now?

I have a 2001 Toyotoa Sienna van. I had thought that I had the automatic transmission fluid changed at about 60,000 miles and so I took it in recently at 125,000 miles to have it changed again. However, the shop asked me if the fluid really had been changed at 60K miles and since they asked, I questioned that myself since I would have thought they would have done it. They had no record of it though. So I thought maybe, that it had been done at the dealer and told them I would check my records. Well, all told, I don?t think it ever got the 60K transmission flush and change. The shop owner said that his recommendation is that they do not change the fluid and let it ride? He said that there may be some dirt/deposit built up on the transmission parts and that putting new fluid (which has detergents in it to keep deposits from forming on transmission parts) in it now could actually break the deposits loose and cause problems. He says he has seen this happen a few times before. It sounds somewhat reasonable but the other question would be what about the breakdown of the fluid itself.



Should I let it ride? If so, what are the ramifications? Anybody experience this issue or hear of it? Any other suggestions? I thought about suctioning out a portion of the fluid, discarding it, and topping it off with new so that the concentration of the detergents was less. I could do this over a several month period.

None-sense. Have the fluid changed now.

just do it yourself. drain the fluid. replace the fluid. drive 5-10 miles. drain the fluid and add new fluid. that should do.

and change the filter if it has one on the 1st drain and fill. it’s easy. might takek 3 hours but you can do it.

Here’s why this comes up so often: Mechanics are loath to change trans fluid on a unit that hasn’t had it done regularly because, as this one stated, new fluid could well break loose all kinds of accumulated gunk that could potentially lead to a failure. The next logical progression is that the car owner will take it back to the guy who changed the fluid, screaming “You ruined my transmission!!” and demanding that they replace the transmission for nothing or next-to-nothing.

It could happen. It could also be perfectly fine; there’s no way to be sure. The fluid should’ve been changed back then, so I’d get it done anyways because it’s probably in dire need. If it winds up crapping out soon after this is done, it was probably on borrowed time anyways.

The filter is a stainless steel screen. If dirty, it can be cleaned with solvent. A new filter isn’t necessary. You can drain the fluid through the drain plug and refill or you can drop the pan after draining the fluid. I recommend dropping the pan as you will find that it will be full of gunk, held their by a magnet.

There is often problems after changing fluid. Of course the real reason there is often problems after changing fluid on a high mileage car is the fact that many people never bother to change the fluid at all until they start having problems and the fluid change is really too late. The damage has been done and a fluid change will not fix existing damage.

I recommend a fluid change where they drop the pan and clean it and the filter.  Don't go for a flush.  

Transmission fluid changes seems to be something that even the manufacturers have neglected and often don't even list it as a standard maintenance item.  I suggest owners of cars with automatic transmission change the fluid every 30 -40,000 miles.