The car is a 1990 Toyota Camry with the 2.0L 4-cyl 3sfe engine and A140E automatic transmission which specifies Dexron II atf. Sometimes when braking/slowing to a stop the car will shake and buck. It is an automatic transmission, but the shaking/bucking is the same as if in a manual transmission car you slowed down really slow but didn't put in the clutch.
The problem appears to somehow be heat/temperature related as it does not occur Fall/Winter/Spring but will reappear in the hot summer weather. Even in the summer, it doesn't happen every time I drive the car. It is more likely to occur if I'm out in the middle of the day heat in a lot of stop and go traffic. A 60 mile drive on two-lane country roads (45-55mph) done in the middle of a hot day saw no problems whatsoever.
It first happened about 3-4 summers ago. At the time I read that a clogged filter could cause that kind of behavior, so I dropped the pan, replaced the transmission filter, and did 3-4 drain refills with Valvoline Maxlife Dex/Merc ATF with a few days driving between each drain/refill. There were no metal fragments on the magnets, just a gray sludge on the bottom of the pan. Problem went away for awhile, but came back the following summer. That time I left the filter alone, but did 3-4 drain/refills using Mobil-1 Mercon V synthetic atf as I'd read that synthetic fluid could stand up to heat better. It again went away for awhile, but came back the following summer when I repeated the drain/refill drill with Mobil-1 Mercon V. This spring, when it started getting hot again and the problem reappeared, I decided to drop the pan again and replace the filter. This time the pan was clean, no gray residue, and the old filter appeared clean as well. My local Walmart no longer carries Mobil-1 atf, and it's really high at the auto parts stores, so I did 3 drain/refills using Castrol Domestic multi-vehicle Dex/Merc. Unlike before, this time the drain/refills have not given any temporary relief.
I took it to a local trans shop that a neighbor had used to see what they would say, hoping that it was maybe a bad solenoid. They supposedly dropped the pan to have a look. They said that sometimes the torque converter clutch was not disengaging and suggested a rebuild to the tune of about 2K.
I had them button it back up so I could think about whether I wanted to spend that much on a 21yr old car.
Since then, I tried adding a bottle of Lubegard red. It's been in a couple of weeks and 300-400 miles. While it feels smoother since adding the Lubegard, it has not solved the occasional episode of bucking/shaking when slowing to a stop.
Has anyone seen or experienced this before? Any ideas what it might be, or what can be done to correct it?
One other thing that may or may not be related. I replaced the original radiator several winters ago with an aftermarket unit from autozone after the original began to seep coolant at the seam on the top tank. It went in just fine, had the nipples for the trans fluid hoses just like what was on the original, and have had no water temperature issues since then, but I have wondered if somehow the built in trans cooler wasn't working as good as the one in the original radiator.
Some other things I have thought about trying, short of a trans rebuild, or a replacement vehicle, are going back to a synthetic Dex/Merc atf and/or plumbing in an auxiliary transmission cooler. I also have a leftover bottle of Auto-RX that I could try in the transmission.
It may just be time to let the old girl go, but I still like the car and would prefer to not be saddled with a car payment again if possible.
If anyone has seen this before, I'd appreciate hearing what it was and what it took to fix it. I figure it's worth getting some advice/suggestions/ideas before I do anything drastic. Thanks for any input and my apologies for the length of the post.
The problem appears to somehow be heat/temperature related as it does not occur Fall/Winter/Spring but will reappear in the hot summer weather. Even in the summer, it doesn't happen every time I drive the car. It is more likely to occur if I'm out in the middle of the day heat in a lot of stop and go traffic. A 60 mile drive on two-lane country roads (45-55mph) done in the middle of a hot day saw no problems whatsoever.
It first happened about 3-4 summers ago. At the time I read that a clogged filter could cause that kind of behavior, so I dropped the pan, replaced the transmission filter, and did 3-4 drain refills with Valvoline Maxlife Dex/Merc ATF with a few days driving between each drain/refill. There were no metal fragments on the magnets, just a gray sludge on the bottom of the pan. Problem went away for awhile, but came back the following summer. That time I left the filter alone, but did 3-4 drain/refills using Mobil-1 Mercon V synthetic atf as I'd read that synthetic fluid could stand up to heat better. It again went away for awhile, but came back the following summer when I repeated the drain/refill drill with Mobil-1 Mercon V. This spring, when it started getting hot again and the problem reappeared, I decided to drop the pan again and replace the filter. This time the pan was clean, no gray residue, and the old filter appeared clean as well. My local Walmart no longer carries Mobil-1 atf, and it's really high at the auto parts stores, so I did 3 drain/refills using Castrol Domestic multi-vehicle Dex/Merc. Unlike before, this time the drain/refills have not given any temporary relief.
I took it to a local trans shop that a neighbor had used to see what they would say, hoping that it was maybe a bad solenoid. They supposedly dropped the pan to have a look. They said that sometimes the torque converter clutch was not disengaging and suggested a rebuild to the tune of about 2K.
I had them button it back up so I could think about whether I wanted to spend that much on a 21yr old car.
Since then, I tried adding a bottle of Lubegard red. It's been in a couple of weeks and 300-400 miles. While it feels smoother since adding the Lubegard, it has not solved the occasional episode of bucking/shaking when slowing to a stop.
Has anyone seen or experienced this before? Any ideas what it might be, or what can be done to correct it?
One other thing that may or may not be related. I replaced the original radiator several winters ago with an aftermarket unit from autozone after the original began to seep coolant at the seam on the top tank. It went in just fine, had the nipples for the trans fluid hoses just like what was on the original, and have had no water temperature issues since then, but I have wondered if somehow the built in trans cooler wasn't working as good as the one in the original radiator.
Some other things I have thought about trying, short of a trans rebuild, or a replacement vehicle, are going back to a synthetic Dex/Merc atf and/or plumbing in an auxiliary transmission cooler. I also have a leftover bottle of Auto-RX that I could try in the transmission.
It may just be time to let the old girl go, but I still like the car and would prefer to not be saddled with a car payment again if possible.
If anyone has seen this before, I'd appreciate hearing what it was and what it took to fix it. I figure it's worth getting some advice/suggestions/ideas before I do anything drastic. Thanks for any input and my apologies for the length of the post.