Auto trans sticking in higher gear when slowing to a stop.

[Camry215K]

1990 Camry Dx, 2.0L I4 (3SFE) with A140E automatic transmission, 271K miles.

When braking, slowing to a stop, auto trans is staying in a higher gear and not downshifting causing the car to buck. It will eventually downshift, doesn't cause the car to stall out, but not before making the car buck and shake pretty severely. It doesn't happen all of the time, but often enough to be troubling. An extended period of bad traffic stop & go will sometimes
bring it on, otherwise I am unable to reproduce the problem at will.

Problem seems to be temperature/heat related as it rarely occurs fall/winter/spring, but recoccurs come late spring/summer. First happened
3-4 summers ago. Replaced atx filter & did 3-4 drain/refills of atx fluid using Maxlife DEX/MERC which seemed to help. Problem reoccured the next summer, that time tried 3-4 drain/refills using Mobil1 synthetic MERCONV atf because I'd read the syn fluid could handle the heat better, but again problem came back the following summer. Again did 3-4 drain/refills using
Mobil1 MERCONV synthetic fluid. This spring, less than 1 yr since the last set of drain/refills with M1 fluid, the problem is back. Replaced the atx filter again and have done 3 drain/refills, this time using Castrol Dex/Merc domestic multi-vehicle fluid. Old transmission filter still looked clean and pan was still clean - no gray residue like there was with the first filter replacement.

There are no transmission codes - no blinking OD off light, and with the E1 & Tt terminals shorted using a paper clip, the OD off light blinks at a regular interval. No check engine light.

Anybody out there had this problem with their A140E Transmission?
Any transmission gurus know what causes this? Any suggestions or advice on how I can identify what the problem is would be appreciated.

[holmesnmanny]

Trans-X it and call it a day.

[dem2757]

speed sensors, solenoids. its a list you can check. looks like the tranny itself is working mechanically sound. the solenoids can burn up or become slow

[holmesnmanny]

the solenoids can also stick, I think trans-x best attribute is loosening up solenoids.

[white90dx]

Are you 100% sure you have the correct fluid level in the trans? Can you remove 1/4 to 1/2 a quart and see how it performs?

-Charlie

[holmesnmanny]

One thing I've noticed is that you actually want the fluid to be less than full so that in situations when the temperature rises a lot such as in extreme heat the fluid never goes over the top hot fluid notch since transmission fluid expands with heat.

[Camry215K]

Thanks for the replies guys.

I believe I had the level correct, though I have always tried to get it to the top of the hot marks when taking a hot reading, so maybe that is too much? Where do you guys refill yours to when you change out the ATF? I get pretty frustrated trying to check the level. It is always smeared on the initial removal and it seems I can only get one shot at wipe/reinsert/repull & read before it starts to smear and and get difficult to read.

How far do you guys drive to get the trans to the proper temp for a hot
reading? I've been taking it out on two-lane country highways for 10-20 miles, pull back into the garage, put it in park, then take it through each gear, pausing maybe 5 seconds at each stop til I get it back to park, and then with it still running in park, get out to check the dipstick. I can't remember whether it was the owners manual or a Haynes manual, but I read somewhere that said it should really be checked hot for an accurate reading, that the cold readings only gave a rough approximation. Would it be better to only fill to the lower of the hot notches, or somewhere between the two but lower than the high mark? I seem to get a clearer reading when I do a cold reading, let it sit overnight, crank it up, cycle through the gears, and check the dipstick, but something said that wasn't as good as doing the reading hot.

I took it to a transmission shop that a neighbor recommended. They said a clutch was not disengaging, causing the shaking, & recommended I have it rebuilt. The up side to having it rebuilt, would be that I could have the leaking rear main seal replaced while they had it apart, and while expensive (~2.0K quote) it is still considerably cheaper than a new car.
On the other hand, while it has been a great little car, I can't help but wonder whether it is too much of a gamble to put that much into repairing a 21 year old 271K mile car.

[dem2757]

fluid levels can cause the tranny to act odd. id do the drain a bit and see how the transmission is after that

[holmesnmanny]

Here's what you do before you go spending thousands on a rebuild which will only make the transmission shop happy, not you.

Go down to Walmart and get some Trans-x like I said and two quarts of atf dextron. Use another car if you can. Then go back to your house and drain all of your fluid. Then add the trans-x in. The whole 8 oz bottle. Then add a quart and a half of transmission fluid. Then start the car. Immediately check the fluid. What normally happens is, yes, it smears all over the dipstick so take it out and wipe it, take it out, wipe it, take it out, wipe it,...you can't really do this too many times. At some point it will be clear that it's around the middle of the two "cold" notches. This is what you want. Then drive it around for about twenty minutes, go stop in a mcdonalds drive thru and get some food. Then drive back home and park it and while running check the fluid again. It should have risen to somewhere between the two "hot" notches. What you want is for it to be the middle of the two notches. This is your goal. If it's above that, in between the middle of the two "hot" notches, crack open the drain bolt and let a couple ounces drain out. Then, drive this car for a couple days. The trans-x takes a couple days to work. It will help swell the seals in your transmission and will help to unstick the solenoids.

Here's the deal. If you're going to pay to have the transmission rebuilt, this will not harm you one bit...at the very worst.

All this did was help my own transmission run like it's brand new. After a couple days, report back here. I'd love to hear.