MRecio

Well as the subject says I am having some problems with my tranny. The Transmission went out completly about 3 months ago and I took it in for a rebuild (so any worn out parts were replaced, clutches TC and selnoids were all replaced. well when i got it back it drove like a dream.

about a week after I got it back it started acting up. When i drive it cold it drives normally and soon as it heats up it goes into O/D and locks up just fine but 10-15 more mintues of driving the TC stops locking up. If i keep driving it for another 5-10 mintues it starts really acting up and will with downshift at the slightest throttle touch or wont downshift even with the gas to the floor. and eventually if i keep driving it the AT Temp light comes on.

Well the transmission is still under warranty but when i took it back to the shop they said that the TC and everything should be fine if they work when i first drive the truck and that something it causing it to get VERY hot VERY fast. they are going to replace the temp guage in the trans to see if its bad. but I wanted to ask around here and get an idea of some things that could be wrong with my trans.

The only other thing i can think of it my truck no longer has a fan shroud cause it broke off a year ago. but it never over heated without it before it was rebuilt hard to think it would cause it to now...

whats wrong with my poor trans!!!

4banginRunner

it's a Toyota automatic...nuff said


check the fluid level?
was the tranny cooler ever hooked back up?

mt_goat

Maybe the ATF cooler is blocked.

MRecio

fluid level is fine and has been checked and re checked as far as the cooler being blocked i dont know how to tell or test if it is without hooking it up to a machine to flush it. which i dont have.

MRecio

which line coming out of the radiator is the return line heh.... figured i could at least disconnect it and see if it has good flow coming out the radiator.

mt_goat

That's a good way to tell, just catch the ATF in a very clean container or refill lost ATF with new ATF. The hard line closest to the rear of the tranny is the return line, just follow the hard line forward to the cooler. Its possible debris from the blown tranny clogged the cooler up.

MRecio

Well i checked the flow and it flows very well. the temp sensor in the tranny was also replaced and my mech also wanted to replace the TPS sensor. neither did anything to keep the converter locking up. next on the list is to change the wiring harness going to the transmission. is there anything else i should be checking cause I am running out of ideas...

mt_goat

Call up John here at IPT and have a little chat (http://www.importperformancetrans.com/) My guess is something is wrong with the valve body or one of the solenoids.

MRecio

a bad solenoid would be the easiest bet but the transmission as well as the transfer case was rebuilt from the ground up new seals, solenoids, springs torque converter blah blah... i suppose something faulty could of been put in but they were checked when the temp sensor was changed and they checked out fine. the transmission also works flawlessly while warming up and for about 15-20 min after warm up every time...

I just need to figure out what is happening after that time that is making the transmission not go into lockup. I really wish i had a temp gauge on the tranny instead of that damn dummy light (which by the way does anyone know at what temp the light comes on? Im sure i can search it later though). Heat was the first suspect but it seems clear now that heat is a result of the converter not locking up instead of the cause.

its like the ECT is just loosing communication with the transmission or something... im stumped but i think a third opinion would be a good idea and should give john a call.

Bigblock

Check the TV cable first then pull the pan to see if the screen/filter is stopped up.

MRecio

tv cable? is that the kick down cable located on the throttle body? as far as the filter... the pan has been drained and dropped about 4 times this week and have never seen anything in the screen.

abecedarian

what type of ATF are you using?

mt_goat

Things as small as lint from a rag can cause problems with soleinods. With a rebuild it would be very easy for something to get over looked and get in there. Plus did you flush out the ATF cooler and lines after the tranny was blown?

The ATF temp light comes on at a little over 300* F.

MRecio

Well guys the transmission is fine... we hooked up a manual switch to lock the TC and it works like a charm... now I just got to find the culprit as to why it wont lockup when its suppose to... I figure the it has to be the computer or a bad brake switch what do you guys think?