REALLYRURAL Posted September 13, 2020 Share Posted September 13, 2020 So the 1991 Toyhome I have been working on for two plus years came together enough last week to actually insure register and start some small road trips with. The transmission immediately started slipping, jumping in and out of gear and after getting gas two miles from home it just stopped moving except for reverse. A 75 buck tow later I have it back in the driveway. After a few days of research I have decided to pull the transmission and do an autopsy on it. Based upon the autopsy I will either rebuild it myself or find other options. The Back Story. The trans was slipping when I purchased it so I flushed it in the the parking lot of an auto parts store with 5 gallons of fluid. It then stopped slipping and the hundred miles to home went fine with a mix of interstate, two lane highway and local roads. I did not baby it. The cruise control worked perfect (much different than my 88 with the 22re) and the thing had plenty of power. Two years later I had rebuilt the thing to the point it could go down the road again. So I tossed the plate from 1988 on it and took it for a hundred mile run. The thing ran down the road perfect.... Not a hint of a transmission problem or anything else going wrong. This lead me to spend the last month working on this project without any thoughts of transmission problems. Back to the present . It has a great reverse but no forward whatsoever. If I could find it the emoji with the head banging the wall would be here... So I have spent the last four days looking into the A340E, have learned many things, seen many videos, pictures, pdfs, and have formed the opinion that there is not real danger in the actual dismantling of an A340E once it is on the bench (it has nothing spring loaded or pre loaded to surprised. Has a bunch of cir clips).. . The real danger lies in pulling the trans in your/my Backyard on the ground. I have spent today setting up for dropping the trans out the bottom uneventfully. Hope fully. So I am setting up to drop the trans and dissect in a way that I can share what is learned about the process. If anyone here has dropped one of these before any input you can provide might be a godsend. Quote Link to comment Share on other sites More sharing options...
REALLYRURAL Posted September 14, 2020 Author Share Posted September 14, 2020 So after having Walter (Walter is my neighbor and has a ramptruck the next size up from mine) drop the 1991 in my drive I jacked it up and pulled the pan off the transmission. It has 61000 miles on it and I did not find anything in the pan or on the magnets that was of any concern. I pulled the three servos then tested them with power and pressure and they worked perfectly. A friend has offered me an entire T100 4wd with 144,500 on it for 150 bucks. This has a blown head gasket. The T100 4wd has the A340F which is from what i have found is convertible back and forth. Different output shafts require a gut and put back together. It is possible to convert the 340e to a 340 F and vice versa. However, how the valve bodies set up might be different. I am hoping to travel all over the planet with this Rig so getting the transmission right at this point is really important to me. Quote Link to comment Share on other sites More sharing options...
linda s Posted September 14, 2020 Share Posted September 14, 2020 Well the a340f is for 4x4's. To use on a 2wd your going to have to switch the output shaft and the adapter for the transfer case. I think you can use the ones from your old trannie but not sure. Almost no one ever goes from 4x4 to 2wd so not a lot of information about it. Also from 8/90 to 8/91 the trannies used a funky speed sensor in the trannie to talk to computer. If the T100 one doesn't have it your computer won't understand it if your manufacture date is then. Linda S Quote Link to comment Share on other sites More sharing options...
REALLYRURAL Posted September 24, 2020 Author Share Posted September 24, 2020 So I now have the trans out of the the donor T100 ( I call it Rusty Blue) and the Trans out of my 1991. In addition I have stripped use full parts and the computer out of Rusty Blue. I was going to drop it off at the scrap yard first thing this morning but it still has parts that are desirable. I am thinking about that 130 dollar pump in the fuel tank. The differences in the transmissions. So once I got Rusty Blues transmission out I cleaned the id plate and it is a 30-40 LE which is the same id that plate that is on my 91. It has a different deeper base, the dipstick is 2 inches shorter on Rusty and they both have the speed sensor. The 1991 also has a speedometer cable while rusty does not. Rusty Blues output shaft is much shorter than the 91 so I need to swap those out . Bolt patterns seem the same at this time the neutral safety switches are very different and the computers have the same numbers. Rusty has a sensor on the output side of the trans cooler close to the transmission. I suspect this sensor is located elsewhere on the 91 . I need to clean the outsides and drain both of these before I can start pulling these apart. Quote Link to comment Share on other sites More sharing options...
REALLYRURAL Posted September 25, 2020 Author Share Posted September 25, 2020 So I did the autopsy on the 1991s transmission today. It turns out the answer to the question of what gets damaged when you flat tow a vehicle with automatic transmission is that the parts that are hooked to the output shaft. In the A340 series has the forward/direct clutch package locked onto the out put shaft. It is the only section of the trans that turns when flat towed. This sections turns without any lubrication and in this case just got so hot it turned the metal blue and caramelized the transmission fluid. Since everything is extremely overheated and glazed the plates and disks just slide by each other and all forward movement is lost. I found nothing else that looked amiss in the transmission except this section that is hooked to the forward end of the tail shaft. Quote Link to comment Share on other sites More sharing options...
WME Posted September 26, 2020 Share Posted September 26, 2020 A thought from my deep, dark past as a no budget hot rodder. We used to over fill an automatic when we flat towed to and from the races. Do you think there would be enough splash lube to save the front pack in an emergency tow?? Quote Link to comment Share on other sites More sharing options...
Maineah Posted September 26, 2020 Share Posted September 26, 2020 The governor assembly is supported by the drive shaft tail bushing if it's toast it will trash the case with the governor sealing rings. I'm guessing they still make a case bushing kit for the governor bore. All forward gears involve forward clutch pack. Reverse does not. Everything is connected to the output shaft from low to reverse depending on what is selected. The higher gears will be the first to suffer because of the torque factor same goes for the forward clutch pack because it is always engaged moving forward. Kind of sounds to me like it was just time for an OH. The MH alone is a burden on the trans so add a trailer your looking for trouble. Quote Link to comment Share on other sites More sharing options...
Maineah Posted September 26, 2020 Share Posted September 26, 2020 20 minutes ago, WME said: A thought from my deep, dark past as a no budget hot rodder. We used to over fill an automatic when we flat towed to and from the races. Do you think there would be enough splash lube to save the front pack in an emergency tow?? The whole assembly is pressure lubed. Quote Link to comment Share on other sites More sharing options...
REALLYRURAL Posted September 28, 2020 Author Share Posted September 28, 2020 WME is correct. The only thing connected directly to the output shaft is the front pack and I may have been able to flush/add lucas and mess with it to keep it working, as I did to drive it home. However, If this section was not replaced I would be dealing with it forever. The only reason I have not just purchased another transmission is that no one could explain to me what might be wrong with this one. WME said 'A thought from my deep, dark past as a no budget hot rodder. We used to over fill an automatic when we flat towed to and from the races. Do you think there would be enough splash lube to save the front pack in an emergency tow??' I would not tow anything with this transmission anymore than needed to get it to a safe place. If you can run the engine then tow it anywhere. The pictures show around a hundred miles of being dragged around on a flat tow. It did not need to happen. Quote Link to comment Share on other sites More sharing options...
REALLYRURAL Posted September 28, 2020 Author Share Posted September 28, 2020 On 9/25/2020 at 8:25 PM, WME said: A thought from my deep, dark past as a no budget hot rodder. We used to over fill an automatic when we flat towed to and from the races. Do you think there would be enough splash lube to save the front pack in an emergency tow?? Well you are putting an emergency tow out there. If your doing anything over getting to the next parking lot. Drop the rear end of the driveshaft and use a coathanger to hold it up. Quote Link to comment Share on other sites More sharing options...
REALLYRURAL Posted September 28, 2020 Author Share Posted September 28, 2020 So here is a picture of the trans mostly put back together. I am not convinced that I have got this done properly so it will be torn down again and put back together. Maybe, I can post something that someone needs to know on the next attempt. Any thoughts? What should I present on the tear down and rebuild? What do you want to see? Quote Link to comment Share on other sites More sharing options...
Maineah Posted September 28, 2020 Share Posted September 28, 2020 The clutch pack is flat burnt up probably from years of using OD. Quote Link to comment Share on other sites More sharing options...
Maineah Posted September 28, 2020 Share Posted September 28, 2020 Flat towing will eventually do damage not to the clutch pack because none of them are engaged but to revolving parts because the only lube is from pressurized trans fluid from the front pump they are not splash lubed. The governor is directly connected to the output shaft it turns all the time including flat towing it was a weak spot in the early all clutch Toyota trans because the sealing rings trashed the governor bore I'll assume there are still repair kits available. All of that clutch gook is in the valve body now it needs to be dismantled and meticulously cleaned basically a major overhaul. One more hint everything needs to be shiny clean including the insides of the clutch packs nothing should be left but shiny metal because the new flud is highly detergent and will wash any leftover goo off and it will end up in things like the valve body and the governor. Quote Link to comment Share on other sites More sharing options...
REALLYRURAL Posted September 29, 2020 Author Share Posted September 29, 2020 So here is the repair manual for the A340/f/h:http://kai.supramania.com/Supra/A340 Series Repair Manual (RM216).pdf This is not similar to the A43D and does not share its problems. The problem with this a340E is that it was towed and the front planetary gear is splined to the output shaft. That planetary gear turns the frontplanetary ring gear which slips into the clutch spacers and turns them within the plates. See pages at110 thru at112 of the repair manual. Here is a nice tear down video that has been very helpful: Quote Link to comment Share on other sites More sharing options...
REALLYRURAL Posted October 2, 2020 Author Share Posted October 2, 2020 So I spent the entirety of this day alone bolting this trans to the engine. If you are alone there is no room for error and one needs to firmly strap the trans to the jack so you can the front/forward and side to side controls a cheap trans jack provides. I used another jack to move the engine back and forth. It was not any fun but at the end of the day I have the trans bolted to the engine and have the trans jack removed with the tail end setting on blocks awaiting the install of the trans mounts. Every bolt can be accessed by hand and then tightened with extensions and a unaversul I lost a good friend https://www.penbaypilot.com/article/dale-e-lindsey-service/139174 I had him in mind while working on this project today. Quote Link to comment Share on other sites More sharing options...
linda s Posted October 2, 2020 Share Posted October 2, 2020 So sorry to hear about your friend. He was much too young to leave us. Linda S Quote Link to comment Share on other sites More sharing options...
Maineah Posted October 2, 2020 Share Posted October 2, 2020 As I said before flat towing any automatic will damage it eventually they are pressure lubed no pump no lube. The disengaged clutch pack clearance should be enough not to cook the clutch pack but anything is possible. Quote Link to comment Share on other sites More sharing options...
extech Posted February 23, 2022 Share Posted February 23, 2022 and people think i'm rude Quote Link to comment Share on other sites More sharing options...
linda s Posted February 23, 2022 Share Posted February 23, 2022 I used to be able to put people on time out but after the website went down I no longer can. So reallyrural. It's behave or be gone your choice. Linda S Quote Link to comment Share on other sites More sharing options...
Scott iv Posted February 23, 2022 Share Posted February 23, 2022 There will always be a variety of opinions on how to repair something. No one right way to do most things. Quote Link to comment Share on other sites More sharing options...
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