1992 4wd auto trans shift problems - hrlp!!!

[jimcc]

Most of the time this transmission acts up, sometimes it acts prefectly. I think there are two distinct problems - one is tied to the overdrive solenoid. I have heard it is external to the transmission. Quite often the transmission just remains in OD, press the button on the shifter and the OD off indicataor comes on but the trans remains in OD. Sometimes it starts blinking as it detects an error. The other problem is when you slow or come to a stop the transmission refuses to downshift and remains in one of the higher gears so when you step on the gas it goes nowhere. If you manually pull the shif lever to the lowest gear the car starts out fine and then you have to manually sifit it through the gears. You can tell when it will malfunction at a stop, if you lift your foot from the brake and it wants to edge forward it is fine, if it has malfunctioned then it wil not edge forward. When the transmission works fine ( less and less often) it is strong and shifts perfectly so I doubt it is the typical transmission shop "it needs to be rebuilt" proble. I suspect some electrical problem in the solenoids that control the fluid for downshifts or up shifts. Any suggestions here?? Thanks for the help. I have seen the posts on the temperature sensor regarding engine coolant temperature - i wil look into that.

[Taurus_Guy]

Hi, Just thoguth i woujld let ya know i had same problem ... a few shops told me .. i needed a new Tranny (easy way out, but costly to the owner) .. but I refused to take that for an answer to my problem ... So .. what i did first was go to toyota and get a diagnostic check like 45$ canadian and then what you probably need is new solinoids ... if your gonna replace 1 .. replace them all .. dont do what i did and replace each one as it broke because than ya gotta re/re the tranny pan and electrical components each time at a HUGE cost, cause if one goes .. the rest are soon to follow. My truck started out by not down shifting into 1st at a stop and would intermitently downshift everynow and then and surprise you with power that ya didnt expect. In the end .. replaceing all my solenoids cost me almost what a new tranny would have in the first place .. but ONLY because i didnt replace all the solenoids at the same time ... but it took about 6 months between each repair so i guess it comes down to what you can afford at the time. Each repair cost me about 1200$ canadian at toyota .. and the solenoids are about 600 canadian each plus re/re labour. And if ya try and get a cheaper shop to do it the solenoids stil come fomr toyota and cost the same . but you might get a better shop rate .. but take in mind .. that you get what ya pay for. I hope that helps. Just my 2 cents.

Cheers!!

[jimcc]

Thanks for the info Taurus_Guy . That is a good start, I will drop the pan, change the filter and try to see if there is any crud in there. I took a look underneath last night and I noticed whoever removed the pan last time put a lot of silicone sealer around the gasket. Gasket sealer and automatic transmissions don’t mix real well if particles (silicone or regular sealer) get into the transmission fluid. The fluid passages for some of the control valves are small and they can be blocked or partially blocked. I ran into this situation several years ago with an overdrive unit that a shop had rebuilt and the mechanic had used so much Permatex to seal it that it plugged oil passages. On this 4Runner the previous owner took it to Toyota and they said they do not sell rebuilt transmissions and the cost to replace (you have to buy the transmission and transfer case together) with a new unit would be $4,000 U.S. I thought it was insane but since then I have heard another owner repeat the same thing. The cost of the solenoids (as you mentioned) also sounds outrageous. I’ll dig into this further. The truck is very nice, AC is ice cold, body is great (original Florida car), I am the second owner, but it is not worth sticking a lot of $$ into.