Upcoming transmission work - Toyota Truck

[chestand]

My 1995 T100 is exhibiting symptoms of failing solenoids in the A340E transmission. After 468k miles, it doesn't surprise me. Specifically, of the three solenoids the first gear and OD lockup ones are failing. Symptoms included not shifting to low at a stop, the "OD Off" light flashing on the dash, and lockup at highway speeds not consistently working. Bought a kit from Amazon for less than $70 that includes all three. From what I understand, it's a simple procedure after the fluid is drained and the pan is removed. One 10mm bolt holding each solenoid in and one electrical connector for each. Pull the old ones out, put the new ones in, reinstall pan, refill fluid and you're done.

The A340 is used in a number of Toyota and Lexus applications.

I will post a subsequent writeup after. The parts are scheduled to be here Wednesday.

 

[Klutch9]

In general, I think you are correct; once the pan is removed, they are staring you in the face. In my old Focus, this was the case. Each solenoid had one bolt holding it in and a little wire harnes attached to it. The hardest part about replacing them was figuring out if the numbering went right to left or left to right. Otherwise, very accessible.

 

[Astro14]

I've got the A340 in my 4 Runner. Only 265,000 miles. Replaced the solenoids as you outline and it is easy. It did not fix my lack of OD on the highway, however. I believe that the OD clutch in the converter is simply fried in my case. I drive the truck without OD on the highway, installed a plate type cooler and remote filter mount, and keep an eye on the transmission temp via an Autometer gauge mounted on the A pillar.

 

[Donald]

I would have bought OEM ones. Maybe the Amazon ones were. Use Amsoil ATF and your good to go.

 

[caravanmike]

i have replaced them on an aw4 (same transmission). hardest part is getting pan off and cleaned up. I replaced mine with suitable salvage yard soleniods for $15 that ohmed out good. worked great.

 

[meep]

this is music to my ears. I hope the A750 is ends up being just as stout. With 130k and tow duty its whole life, it doesn't miss a beat, but my goal is 300k and it's got a way to go to get there.

I had an AW4 that was crazy-reliable and yes, those solenoids were easy to get to.

IIRC these A/W transmissions don't use much clutch material--- it's designed to shift "perfectly" and consume very little. Therefore there shouldn't be much debris in the pan. When I did my AW4, this was true-- very little sludge/staining--- but it had two shims that had snapped and sat in the bottom of the pan.... maybe 30mm OD and 20mm ID and maybe 0.2mm thick. Didn't know the history, if it was a rebuilt unit or oem, but I put dexVI in it (it was a 1993 model car) and the trans continued on like it was new.

Solenoids are cven easier to reach on a chryco 41TE, but the design makes it very hard to prevent dirt from getting in while doing the job.

m

 

[SwampSurvivor]

I wish Toyota hadn't stopped making them. However, a Tacoma with the A340 is something I'll always buy in a heartbeat (if the frame isn't rusted). They are just such great transmissions!

I would say at 468K it's due for some solenoids. That seems to be the only real way to "burn up" one of these. Let the solenoids go bad long enough and they won't be happy.

It's been in vehicles made by:
- Isuzu / Honda
- Mitsubishi
- Jeep
- Lexus / Toyota
- Volvo


Originally Posted By: meep
this is music to my ears. I hope the A750 is ends up being just as stout. With 130k and tow duty its whole life, it doesn't miss a beat, but my goal is 300k and it's got a way to go to get there.

I had an AW4 that was crazy-reliable and yes, those solenoids were easy to get to.

IIRC these A/W transmissions don't use much clutch material--- it's designed to shift "perfectly" and consume very little. Therefore there shouldn't be much debris in the pan. When I did my AW4, this was true-- very little sludge/staining--- but it had two shims that had snapped and sat in the bottom of the pan.... maybe 30mm OD and 20mm ID and maybe 0.2mm thick. Didn't know the history, if it was a rebuilt unit or oem, but I put dexVI in it (it was a 1993 model car) and the trans continued on like it was new.

Solenoids are cven easier to reach on a chryco 41TE, but the design makes it very hard to prevent dirt from getting in while doing the job.

m


They shift hard and quick, but they do so forever. I try to be as easy as possible, but I have seen many occasions where people just beat the daylights out of these transmissions off road and they simply never fail.

A few years ago I was riding with a guy in a Cherokee and he rocked it in the mud for a solid 20 minutes. I don't mean that he rocked it a few times, got out and surveyed, then hopped back in ... it was 20 solid minutes of Drive, foot to floor, brake, reverse, foot to floor, brake, drive foot to floor ... The only reason he stopped was he ended up pegging the temperature gauge on the Jeep. We could smell the transmission fluid burning. All he did was change the fluid.

4 years later, it's still on the road and running.

I did similar this winter and last when doing some winter wheeling. Not as severe, though.

 

[chestand]

Yeah, I know this a little "out there" for most people, but IF there were an auto transmission hall of fame, the A340 would surely be there. So would the GM TH350/400, the Chrysler Torqueflite, and the Ford C6. I've never had this kind of mileage from an original automatic transmission with only this one issue.

Keeping clean ATF in it for its life may have helped some too.

 

[zzyzzx]

Originally Posted By: chestand
From what I understand, it's a simple procedure after the fluid is drained and the pan is removed. One 10mm bolt holding each solenoid in and one electrical connector for each. Pull the old ones out, put the new ones in, reinstall pan, refill fluid and you're done.


Yes, it really is sometimes that easy, assuming that you don't have to remove the valve body. I've done it (no valve body removal required) and took a bunch of pictures along the way here:
http://www.feoa.net/threads/how-to-replace-1-2-shift-solenoid-on-atx-1991.82837/

 

[SwampSurvivor]

On the A340 it's pretty simple - just drop the pan and there they are.