transmission ?
 

Hey everybody

I've asked a few general questions in previous months. Almost all have dealt with my a 340 h tranny. I have yet another question. Some background: I've had codes pulled; I know that I need to replace my no.4 solenoid for sure. I was also told that my o/d what not working correctly, however, they didn't indicate that this was a solenoid issue. It has been a few months since diagnosis and I'm still creeping around with it. The overdrive seems to shift fine and everything but after about 30-40 miles of continuous driving @ 65-70mph it gets hot and the "a/t oil temp" light comes on plus the transmission hump gets "smokin'" hot. I have found that if I need to use it for long distances I can turn the o/d button off and the truck does fine (no heat, no light) but I'm limited to a top speed of 55mph @ about 2800-3000 rpm and I don't wish to push it much more than that because it can't be good for it. Anyhow my question "Is the torque converter responsible for the super heated atmosphere?" I'm thinking if that's the case then my brother could help me put in a new one along with 4 new solenoids. Another thing I've been speculating about is ordering a used tranny to install. Thanks in advance for any insight!!

when the torque converter is locked up there is no slip so therefore no heat. you could be running hotter becuase the fluid is not moving around how its supposesed to be (bad pump, low pressure) or you could be low on fluid. anyway i have only done solenoids in a a340F im guessing becuase you say no 4 solenoid you hav an a340H that is located in the rear tranny pan. pull the pan and it should be right there. if im not mistaken the no4 solenoid controlls the 4wd activation, being that your transfer case is hydraulicly controlled via ATF. all together is an easy job

Mebbe this is too simplistic. But-- have you made sure that your tranny is not overfilled? Mine was over by about one quart when I purchased it. Drove it all day and the ambient air temp outside was about 70 degrees; so not too hot. Most of this driving was on the interstate at about 70 mph. I turned off the interstate and was going about 60 mph and my A/T Temp light came on. So I pulled off the road and parked for about 15 minutes to let it cool. When I got home, I checked the fluid level and it was overfilled. I drained out enough to take it down to the proper level and have had no problems since. That was almost two years ago.

Mike in AR
1992 3.0 V6 A340H A/T 4.56 gears now on 31x10.50's

thanks for the reponses guys. I've been very attentive to the fluid level for that very reason. As far as I know it has not been an issue. One thing that came out of the diagnostic I had done was that the ratio for the overdrive (or something to that affect) was supposed to be 2.1:1 and instead mine was like 16:1. I have mistakenly thought that perhaps this had something to do with the torque converter. How long do you think I can use my tranny as a virtual "3speed" by keeping my o/d turned off? What I'm getting at is would 2800-3000 rpms for distances up to and including 50 miles be rough on my motor. I would assume so. Unfortunately, it's my go to work rig and I have to put these kind of miles on it.

my 5 speed in my truck came stock from the factory pushing 3500k at 75 mph which i routinly do crusing down the intersate for hrs on end.

its a toyota engine, they make there power up there, this ant no diesel!

I dont think 2800 is too high, personally. I towed a trailer on the interstate with the O/D off and was typically around that RPM with no problems. The trip was over 300 miles each way. My 3.0 seems to pull best after 2800 , anyway. However, I can see how you'd like the lower RPM on the highway to lower the engine noise. Those injectors can get a little annoying after a long trip.


Mike in AR

thats nothing man with my 5 speed and 5.29s i go on 3 hours trips doing 3300 rpms at 75 miles an hour. if its a 22re it can handle it all day long

When pulling my boat with O/D off (which it should be if the trailer is heavy) I always cruise at 3500.

I've got codes for my #1 and lock up solenoids, my truck won't downshift so i have to drive it manually. I have an 89 4runner with a 22re and was wondering if the a340h from the 3.o v6 is the same and if i could throw a donor from a 3.0 in mine. I see tons of a340h trannys for sale from the 3.0.

Tho I've never done it, looks like changing the solenoid(s) is not a big deal. Why not just replace the solenoid(s) that you need to and go from there?

Look here:
http://personal.utulsa.edu/~nathan-b...38onvehicl.pdf

Mike in AR

no it wont work bellhousings are different howevever not sure if the bells are swappable

how about the solenoids? are they the same on the two different engines? and where is a good place to order replacement solenoids?
thanks

solenoids are all the same in any a340 series as long as you dont corse them around although the no1 on no2 solenoids can be mixed. if you use a shift solenoid in the place of a lockup you will have a constant shutter and the tranny will blow before you get out of your driveway so if you go swapping them just make sure you mark em

thanks for all of your responses, i appreciate them. someone asked the question about where to purchase solenoids for the a340 series. I am wondering myself. Could a stuck #3 solenoid be the reason why my transmission gets too hot?

most likely not. the solenoids ony switch fluid from going into different valves which then control shifting. www.transtec.com look for distributors in your area.

another quick question for the experts. Could it be a faulty transmission cooler? I didn't install it and I haven't even really checked to see if it functions, i just assumed it did. What if I were omit it or replace it? I think that it would certainly explain a problem with the tranny getting too hot. Don't you?

bump.

I suppose the cooler 'could' be clogged, either internally or externally, but I've never heard of anyone experiencing that. The cooler came standard on A340H transmissions. Drive it until it warms up and then get under and see if the cooler is warm.

If the fluid is at the proper level, then I would think it almost has to be solenoid related. Mine overheated once because there was too much fluid in it. However, it did not affect the shifting -- at least, not at that time . I had purchased the 4Runner in late September and hadn't checked the fluid. The overheating occurred the next May.

MIke in AR

Possibly the no. 2 solenoid? Would a sticking solenoid cause heat like that?

http://personal.utulsa.edu/~nathan-b...30generalt.pdf

You'll note that almost all the abovementioned issues in this troubleshooting section deal with solenoid malfunctions. You can also see if there is a Tranny Check Code (similar to the CEL code for the engine )

http://personal.utulsa.edu/~nathan-b...31diagnosi.pdf
This may help you narrow down an electronic problem.

MIke in AR