afracer

Alright guys, I've tried to search but info seems limited and I wanted to bring this up again and try to hit the nail on the head.

The issue is Toyota auto trans interchangeability...most notably being able to swap out the rare A350 5 speed auto (96-97 GS300) to the much more available A340 4 speed auto (just about every Toyota/Lexus). Why would you want to do this? The 96-97 GS300 transmission is notorious for having problems and since it was only offered two years and only in the GS (pretty much), it's hard to find a replacement and very costly if you do. Externally they are supposedly the same transmission but the A350 combines 2nd/OD to create an extra "5th gear" between 2nd/3rd, so it's got some extra electrical parts internally.

My wife's 1996 GS300 recently started having transmission problems this summer and is now somewhat disabled. One day it started slipping driving around town...we limped it home right away and I installed a tranny cooler and new fluid (the old stuff wasn't that old). Worked great for a couple weeks until on the highway one day wife heard a loud bang and the car won't move in drive or reverse, it just revs freely like it's in neutral. What's weird is if I turn the car off and let it sit for a minute, restart and retry, it'll work like normal for a few minutes, then start slipping and then goes out again. Thiis trans was rebuilt just before I bought the car about 2 years ago too and I've always kept clean, expensive (Toy Type IV) fluid in it. Well, I'm done dealing with this POS 2 year only A350E business and want something more reliable and readily available.

So, I'm wondering if anyone has done a swap from A350 to A340 or anything somewhat related and could share their expertise/experience on the subject. I'm thinking if I swap out the transmission to say a '95 GS300, as long as I use the '95's ECU it should be able to shift the transmission normally. But, will the '95 GS300 ECU hook up to the '96 harness or will it have different plugs, especially since 96 went to OBDII? Does either transmission have it's own ECU? For the sake of conversation lets leave emissions and any legality issues out of the discussion for now. The question is can it be done and how hard/easy would it be? After doing a few searches I know I'm not the only one to have had this question because they're having problems with their 96-97 GS300 transmission.

I'm not opposed to trying it out myself as there is a '95 GS300 in the junkyard here with everything there, but if there are any quick/easy show stoppers to point out, let me know; such as ECU pinouts being different or not interchangeable between 96 OBDII and 95 OBDI, etc.

If it doesn't or can't work easily our backup is to not replace or rebuild our A350E, but replace everything altogether with an Aristo engine set which oddly enough only costs a few hundred more than a rebuilt A350E lol.

afracer

No one?

Cliff notes: Can a 1996 GS300 (A350E) be retrofitted easily with a transmission from a 95 and earlier GS300 transmission (A340)?

kene

iTrader: (2)

With a brief search this is what I came across. (sorry, all I could come up with)

http://www.supraforums.com/forum/arc.../t-399518.html

http://en.wikipedia.org/wiki/Toyota_A_transmission



Save this .pdf to your computer(maybe very well be what you need). Pg 31 lis "troubleshooting"

http://home.student.utwente.nl/gombe...%202JZ-GTE.pdf


This link may help if you do get an A340E and want to do a rebuild with the "high power overhaul kits". He works on the A350E as well it looks like
http://www.importperformancetrans.co...on_guide.shtml
http://www.importperformancetrans.com/toyotaauto.shtml


This guy here on clublexus is installing an Aristo(GS300 turbo - from japan) transmission in his gs300 with pics. He is composing a step by step it seems. this may help you.

https://www.clublexus.com/forums/gs-...-1g-gs300.html







ebay has A350E's for as much as 1,600$(FYI - thats as much as a 2jzgte turbo motor with aristo transmission, ecu and harness). A340E's go for as low as 200$ on ebay private party.


hope this helps... you might want to try to look into going over to a manual shift setup if this A340E thing doesn't work out.

afracer

Thanks. I've seen most of this information with the exception of the repair manual...some of the trouble shooting information was good but it all points to lack of line pressure/bad pump or possibly solenoid 5. Not sure if this info stands the same for the A350 but I will find out soon as there is a manual on the way for it, hopefully it addresses that A/T section in detail like this one did. If it is a bad pump, those aren't cheap either. When whatever it was failed, I was following my wife in my car and she said she heard a bang while driving up the slight hill and then it started slipping big time. While I was behind her I saw some smoke and could smell burning clutch (smells like Campbells chicken noodle soup to me) as she lost speed and pulled over. So I guess it's possible the torque converter went or the A/T pump. The car will sometimes still go into gear and not slip when it's cold/not warmed up which leads me to believe the pump.

Either way I still need to fix it by either replacing the trans or trying to replace the pump and hope thats the only thing that messed up. I'd like to go with the first option and forget using this rare, expensive, and fragile transmission with the earlier one.

afracer

Okay, I'm trying to make some headway but without any luck. I ordered a FSM for the 93-97 and it was crap...it was actually for a '97 only and had barely any info in it. Beware of those Ebay sellers! Worst FSM I've ever gotten online and I think its WAY incomplete.

So, I'm trying to find a ECU pinout for a 93-95 and a 96-97.

I could really use a ECU for a 93-95, so if anyone has one they can let me borrow or buy very cheap, I just want to see if it'll at least plug into my '96...if it does, that answers half my questions...if the car starts with it plugged in, that answers the other half. Then it's just a matter of swapping the trans if it works.

So if there's anyone out there with a ECU I can use let me know! Thanks! I will document with pics if I can make this swap work, just like I did with my LS400 brake swap.

BoostedSC3

man.. i have a dead 97 in the driveway due to trans issues.. i was honestly just going to aristo swap it because before i put 1600 bucks into a trans i could get everything fresh and the car already has 200k on it.

now i have a a340 from an sc400 (won't bolt to a 2j) and they are physically the same.. now heres what i've been pondering..

the trans has a selector switch on the side of it, if you swap everything over leaving the factory ecu in the car it seems like it should control the a340e, as all it does is supply an upshift signal which is carried out by the trans ecu.

I'e been wanting to throw a 40 in there but with me going to vegas in 6 weeks.. time and money arent readily wasted right now.

afracer

Your thoughts are the same as mine. Transmissions aren't all that difficult in operation really, nor have they changed really all that much over the years. I'd think it would work in some way...either the stock 96-97 ECU controlling an A340, or the 93-95 ECU bolted into a 96-97 along with the A340. I just want to ditch that stupid A350. I'm pretty sure ours has a bad pump and/or a bad torque converter. I'm gonna price those out to see how much they are at Lexus.

BoostedSC3

they are expensive if you can get them.. mine ate the front sprag which is 1 piece with the input shaft. goodluck in your quest and keep us posted..

afracer

Okay so I scored a deal on a 95 GS300 engine/tranny setup. Tried to fire up the car using the 95's ECU, but wouldn't stay running... in 1996 (OBDII) they switched to MAP sensor (hotwire) instead of MAF (karman) so to run the 1995 ECU you'd have to switch that over as well which would involve rewiring or swapping the entire harness. I think I'll avoid doing that.

I haven't pulled the tranny out of our 96 GS300 yet, but at the initial inspection, the '95 transmission uses cable controlled pressure vs the A350's electronic. These can be swapped out easily, so that's not a big deal. I can't get visual on the big electrical connector on the other side of the tranny with it in the car, so I couldn't tell yet if there's a difference there or not. From my limited understanding due to lack of information online, the A350E uses 5 solenoids vs the J2 A340's 3 solenoids...the J3 Aristo TT transmission uses 4 solenoids, has electronic line pressure control, and valvebodies are swappable between the NA transmission. So, it may be best/easiest to actually use a J3 Aristo TT transmission to replace the 96-97 A350E! I need to get ahold of one to see for sure.

In the meantime I think I will drop the A350E out of the car and tear into it a little to do some fact finding. As I understand it, the A350E is an A340E with additional solenoids to combine OD with 2nd gear to create the "extra gear". If that's the case, why couldn't I just swap the valve bodies/solenoids from the A350 to the A340 and turn the A340 into an A350??? And not only that, but if I can get ahold of an Aristo transmission and swap the A350 internals into that, I'd get the best of everything. This would be great news for 96-97 GS300 owners, being able to basically create a 5 speed Aristo trans would be pretty cool and make a lot of guys envious.

Worst case scenario, I swap over the electronic line pressure stuff, bolt in the A340, and deal with the car possibly shifting funny. I honestly think it's just a bad pump on our A350E, so when I drop it, if none of this hypothetical swapping stuff works out, I'll have it checked out and maybe just rebuild it myself. Just thought I'd share my progress!

kene

iTrader: (2)

pretty cool, thanks for the update.
please keeo us posted with pics if possible.

afracer

Finally got the A350 out of the Lexus, put it side by side with the A340. The only big, possibly show stopper difference is an additional speed sensor on the passenger side of the transmission that the A340 has absolutely no provision for. One of the electrical connectors on the other side of the tranny has 8 pins instead of the A340's 6 pins. That's all I can see for now...oh also the torque converter is slightly different at the very front race that rides in the flywheel. The A350's is a little shorter it looks like. So now my question is, do I honestly need this extra speed sensor or could I leave it unplugged and still run the A340? Unknown...I'd have to find someone that really knows the A350E to find that out and I have yet to find anyone like that.

afracer

I'm going to see if I can find a good tranny shop around here that can test out the A350E and confirm what may be wrong with it. Still may be better off just fixing what I've got since it's probably just a dying pump. I just want to get her car up and running again at this point because my wife needs her car running.

kene

iTrader: (2)

good stuff..

my buddy at work came across this:



CobraTransmission.com

A340E, A350E, A340H, A340F, AW4
A341E, A343F, A350, R150F Transfer Case
A440F, A442F
A540E, A540H, A541E
A650E
A750E, A751E, A761E

Parts available for the above listed models:

Rebuild Kits:
Overhaul
Banner
Master

Other Parts:
Filter
Brake Band
Bushing
Thrust Washer
Bearing
Pan Gasket
Torque Converter
Recalibration Valve Body Kit

Electrical Components:
Solenoid
Sensor
Wire Harness Repair Kit

Hard Parts:
Drum
Chain
Re-manufactured Valve Body
Pumps
Planetary Gears
Sun Gears and Shells


For parts not listed, pricing and availability visit us on line or contact us at:

786-472-8500
786-486-0335
CobraTransmission.com

_______________________________

Overhaul Kits, Friction clutch plates, and standard clutch plates(for all toyota and lexus models - Free shipping if order is over 250$)

# 97004H Banner kit, A350 (LEXUS GS300) 1996-97
Includes: overhaul kit, friction clutch plates
$ 170.91

OR


# 97002G Overhaul Kit, A343F (95-99), A350E (96-97)
…Basic overhaul kit includes, paper gaskets, O rings, lip seals, metal clad seals and sealing rings.
$ 92.97




http://www.makcotransmissionparts.com/A340.html

afracer

If I had a dang Aristo tranny, I'd swap the guts out and call it a day. Looks to me like only the valve body and additional sensor on the tranny body are the only real big differences between a 350 and 340. They use the same front pump I know for sure, but different filters.

I was able to get an overhaul kit on RockAuto for $80 shipped, should be here in the next couple days. I may end up ordering some clutches and other pieces, but I'm gonna hold off on pulling the tranny the rest of the way apart until the Lexus A350E manual gets here in a few days as well...or I may just pull some of the pieces from the junkyard A340E and swap those in if they look good.

I did call a tranny shop and they said the Lexus trannys do this kinda thing often from the filter getting clogged up. I've always been religious with Toyota Type 4 fluid changes and keeping it clean so it's possible a clutch may have crapped itself and remnants clogged the filter too. There's a thread on SF of a guy with a built A340 and the exact same symptoms as I have and that's what happened to his, so we'll see once I crack this baby open some more. Thanks for the info!

kene

iTrader: (2)

found this 250$ japanese transmission link on ebay for a 2jzge tranny:
Model#: 30-50LE (A350? - 1993? does this make any sense to you)


http://cgi.ebay.com/ebaymotors/JDM-9...Q5fAccessories











And here is the other one for I think an A340(from a VVTI 2jzge -1997)

http://cgi.ebay.com/ebaymotors/98-00...Q5fAccessories