ATF volume inconsistency

This is on my 2005 Toyota Camry. I have been doing fluid drain and refill with ATF IV every 15K miles. At 60K miles I did a pan drop and filter change. Now Toyota does not recommend any fluid change and states that the filter/strainer is good for the life of the car-whatever that means.

Before the filter change, at every drain I would get ~4 qt of ATF out (the manual says the capacity is 3.7 qt). After the filter change, at 75K miles I drained close to 5qt of oil and had to put in another 5 qt to get it up to normal level, so it was not overfilled. I am wondering if my new filter is the reason I am draining more fluid. Could it affect the filtering quality?

When the pan is drained fluid remains in the torque converter, pump, servos and the valve body. The close tolerances keep the fluid in the system from draining. With wear and age, and more so if the fluid is hot and the pan left off for a considerable amount of time, fluid will seep out of the system. To speed the job I marked a 5 gallon bucket at 1 pint increments. The amount drained was rarely the amount specified in the shop manual. The Transman might know something specific to your transmission to the contrary but it is very unlikely that the filter, if correct, had any effect on the situation.

There is considerably more than 4 or 5 quarts of ATF in the tranny…Normally, only 4 quarts can be drained…But sometimes, with everything in the right position, a path opens for more of the fluid to find it’s way out…

I think you might be overdoing the tranny oil changes…

Thanks; the transmission was hot when I did it this time, so maybe that helped. This car has a transmission drain plug, so it is very easy to drain and refill, @ $20 per ATF change I like to have the piece of mind. I know the total capacity is 9 qts, just wasn’t sure how I got out an extra 1.3 qts through the drain plug this time.

There is a difference between pulling the plug and dropping the pan. When you pull the plug, there is a little dam around the plug on the inside so a small amount of oil is trapped in the pan. There is also guck build up in the bottom of the pan, well at least for those of us who are not quite so diligent.

The “filter” is a stainless steel screen, it wont hold any fluid and it will last the life of the transmission, but it should be cleaned out about every 60k miles or so. Its pretty expensive from a dealer and I have had no luck in finding a filter at a parts store that actually fits correctly. Some come close, but there is always something that causes a problem. I would keep the original and back flush it when needed.

BTW, my experience is with an 03 Corolla, very similar transmission, almost identical. 3.5 qts using the plug, 4.1 dropping the pan. That is even stated in the service manual and I have found it to be accurate.

Keith, the 5 qt I got out was just from the drain plug. I bought my filter from Autozone and it fit just fine. I think my OP was not clear. The filter change was at 60K mile and now I am talking about another drain and refill at 75K miles.

Was there gunk in the pan or old filter?
A partly clogged filter could have been holding back some fluid from draining back down into the pan.

Nothing particular, just a bit of black at the base of the pan. Much better than the other transmissions I have serviced. No shavings whatsoever, the filter looked fine too.

It’s good that you take care of your transmission, but I think you could at least double the mileage between transmission fluid changes with no change in the lifespan of your transmission, unless you tow a heavy trailer or routinely beat the crap out of your car. An external transmission cooler would probably go further to prevent harm to the transmission than your very low fluid change intervals. Transmission fluid does not lose its beneficial properties as fast as motor oil does.

galant, my bad, I did not read your post close enough and I thought you did the filter at 75k miles. Now I will only offer this, that filter you got from AutoZone is not fitting as well as you think, but that is just conjecture. In the Corolla, I tried two different kits from AutoZone, neither was even close.

Then I tried a kit from Advance and I thought I had a winner, but when I looked more closely, something didn’t look quite right, so I dropped the filter and compared it to the old one, there was one dimple missing that kept the filter from sitting flush against the valve body. It was so close, but not enough. The gasket from that kit didn’t fit either.

It might have worked OK if I left it, but I just cleaned out the old one and put it in and its been their ever since, 157k miles. Since your transmission is working OK, I would just continue with your schedule. You are apparently doing no harm.

So the OCD in me says that the filter is probably either not sealing well, or not holding as much fluid as the original or maybe is just smaller itself and leaving more room for the fluid. As much as I hated dropping the pan on this particular car (difficult access to 3 bolts), I guess I see another pan drop in my future. The original filter and gasket are going to be $80 from Toyota, add 6 qt of fluid and I am in for $110 and 6 hours of work.

So the OCD in me says that the filter is probably either not sealing well, or not holding as much fluid as the original or maybe is just smaller itself and leaving more room for the fluid. As much as I hated dropping the pan on this particular car (difficult access to 3 bolts), I guess I see another pan drop in my future. The original filter and gasket are going to be $80 from Toyota, add 6 qt of fluid and I am in for $110 and 6 hours of work.

Yeah, and Toyota is proud of that pan gasket too.

If my filter is not seated well, would there be anything noticeable in how the car shifts?

I would think not with the possible exception of a one to two second delay when you first put it into gear after startup, if you throw it into gear as fast as I do, no warmup.

Well, gave in and bought original Toyota screen, gasket and O ring with another 5 qt of Type IV ATF. Dropped the pan and the previous autozone filter was right there, nothing wrong with it. Even the filter material seems like the hard sponge that Toyota sells (AKA screen). The Toyota screen was made in US.
Put everything back together. This time I had bought an offset ratcheting wrench from Harbor freight which helped a lot with a few bolts that are difficult to reach. Te gasket from Toyota is cork, I have not had good luck with cork, so keeping my fingers crossed.
Nonetheless it is a major pita no matter what. I hope I am not doing this again.