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Caring for the A340 Factory automatic trans / built or stock

173K views 265 replies 76 participants last post by  95MKIVTT 
#1 · (Edited)
Rules

Rule #1 - O/D off when you go WOT. If you suck at remembering things like I do, make notes and put them all over the car so you remember to turn it off. The overdrive clutch pack contains 2 clutches, the rest of them are somewhere around 6 if I remember correctly, O/D clutch pack CAN NOT HANDLE HIGH HP YOU WILL BREAK YOUR TRANS

Rule #2 - Double check that O/D is off.. joking? No, I've seen my little reminder notes and hit O/D off twice, turning it back on..

Rule #3 - O/D is still off right?

Rule #4 - Burnouts ONLY in First Gear. Do not let the transmission shift into 2nd during a burnout. You will very likely break the 2nd gear sprag. Tends to break when wheels are spinning on the shift from 1st to 2nd. I'm not a trans builder, I dont know why.. Its just known.

Rule #5 - Trans coolers, lots of them, big ones. I have 3 trans coolers on my car, first one in the chain on the Passenger side air duct in the bumper with a fan on it, from there to another large one in between radiator and intercooler, from there to a small one in the drivers side air duct on the bumper.

Rule #6 - External trans filter mount with the CORRECT type of filter on it. Its $28 for the bracket on summit racing. The filter you want is a Napa #1624 - this is a $20 filter, it is designed for hydraulic/transmission use, and filters to 19 microns. Put this filter BEFORE YOUR FIRST COOLER. The point is not so much to keep the fluid clean as it is to keep junk out of the coolers.

Rule #6a - PUT A TEMP GAUGE ON THE TRANSMISSION LINE OUT. You want to see what the fluid temp is BEFORE it hits your coolers. You dont want this ridiculously high, Ideal is under 220deg. With my stall being so loose, it generates a LOT of heat. We'll discuss this more later.

Rule #7 - Spend the $100 or whatever it costs to get the Lexus IS300 transmission pan, its deeper, allows a little bit more fluid to sit in the pan, and extra fluid means the overall fluid temp in the pan will stay lower

Rule #8 - REALLY IMPORTANT - MAKE SURE YOU'RE FLUID LEVEL IS CORRECT. It's not cut and dry filling the trans, variations in temperature cause variations in fluid level readings. When ever I flush the trans I put back in EXACTLY what I took out (minus whatever extra I flushed through). When first filling a new trans, even with the extra coolers and deeper pan the overall capacity is not going to be way higher than the factory dry capacity of around 8 qts (will update when I confirm the factory capacity for a dry system). I start with around 7.8-8 qts in the system, let the trans warm up, put it into each gear for 5 seconds, P - N - D - D (o/d off) - 2 - L, back up to P again stopping at each gear for a few seconds, I check the fluid level in Park with the motor running. you dont want it at the very top of the "High" line, thats the max fill. When the transmission gets VERY hot (it will if you race), the fluid level can go over the max fill level, this can cause the fluid to aerate, causing air to get into the lines, causing a momentary loss of line pressure, which can cause failures to happen.

Rule #8a - Go drive the car now, make sure it goes into every gear, including Reverse, and drive until the fluid is up to operating temp. Now go back and recheck the fluid level.

Rule #9 - Check your fluid level again

Rule #10 - KEEP THE FLUID FRESH. Change your fluid often, change it like crazy if you race. Keeping the trans fluid in good condition keeps the trans in good condition. Change the external filter even more often. I'd say for a normal street car it's not out of the question to change fluid every 2 oil changes and change the filter ever oil change. For a stock car, just change fluid every 10k unless you absolutely beat the piss out of it.

Rule #11 - Converter lockup. If you have a higher stall, figure it out. (more info below)

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If you have a failure, converter, trans, or contaminated fluid somehow:

Do not be cheap, your trans cost you a good bit of money, you want a transmission that was designed to handle 320 flywheel hp to handle 3 times that? Dont cheap out.

Whenever I have a failure, or my fluid is questionable for some reason - I flush at a minimum 12 qts OUT of the coolers before I begin to fill.

Flushing is easy, disconnect the line from your coolers that goes back to the transmission, put a hose from that line to a drain pan, and turn the car on. Add fluid as it spits out fluid, dont let it run dry if you can. I usually start the car, let it run for 10-30 seconds, shut it off, dump the old fluid into either gallon or qt containers so i can see how much has come out, add more in, and Repeat.

Ideally run AN lines from the trans to the coolers, disconnect the cooler line at the trans so you make sure theres no crap in the line - flush it from that point.

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Locking the converter

Converter lockup is absolutely essential for street driving with a higher stall. And you should do it on a lower stall too if for nothing other than the added fuel economy.

Converter lockup clutches are freakin small, they are not designed to be locked up at WOT - I have never locked my converter at anything over 30% throttle. The OEM ECU wont lock anything over 30% either if I remember correctly. This is because the clutch is not intended to handle power, its there to make the converter 1:1 ratio on slippage, enabling you to get better MPG and keeping trans temps down.

ONLY lock the converter in 4th gear over 50mph under 30% throttle.

Enabling and setting up hysteresis in the AEM converter lockup controls is a must, whenever I dig up my old AEM maps I'll post them. If I havent posted them yet, then I havent had time to find them, dont ask.

Cruising on the highway at 70mph with my converter unlocked, my temps on the way out of the converter will go out of hand, with the converter locked, the temps actually drop, like a brick.

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Drag racing:

Do not let the car go into overdrive. 3rd gear at 8500rpm on a 26" tire should get you 155mph, if thats not enough, go to a 28" tire or change the gearing in the rear.

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Line Pressure and AEM V1:

AEM V1 can not control the solenoids inside the transmission properly! The drivers operate at different frequencies and they will shut down. The AEM will ONLY run MAXIMUM line pressure at all times, THIS IS BAD.

With that said, you can still setup a timing retard on shifts, this reduces power on the shifts and helps the trans live a little longer. The FACTORY ecu does this already, in addition, the factory trac ECU closes the TRAC butterfly inbetween shifts to cut air into the motor, this helps the trans live. You took that shit out though, so either get an ECU that can control things right, or dont bitch when something breaks.

I run a ProEFI for my engine/trans control. It is able to completely control all aspects of the trans. I've bitched about this ECU in the past, but with the newest firmware thats out it seems to actually be shaping up to be decent.

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#159 ·
Guys I have an atf auto, and it's running on a proefi 128 at around 830whp, this particular Trans has been in there almost 2 years, with a ton of street hits and a couple track runs on it, still solid. The proefi is a pretty damn good way to run it IMO, the amount of control for the shift settings, lock up settings, ect. Is a huge help with keeping the Trans lasting and lasting
 
#160 · (Edited)
I've run the ProEFI with my BL auto on the street for 3 years with a 4000 stall. Prior to that I ran the old school Gforce ECU for 5 years with the BL. Just purchased the ATF tranny and the FTI 4000 stall converter from Induction Performance. Putting BL up for sale ... still running strong when removed. Was not a daily driver.
 
#162 · (Edited)
I hate to bring up this topic again, especially after reading the full thread, but I am just curious what types of fluid people are running now.

In this thread I realize everyone is saying they should use Toyota Type T-IV, however the a340e 2JZ-GTE FSM states Dexron II or equivalent. I also see that some people are running Dexron III. My question is did Toyota come out with a statement that the Auto Trans should be changed from Dexron II as the manual states to Type-IV or is it something people are just doing? (Same question applies to Dexron III, which my dealer is telling me to use)

I am replacing my fluid and it is BROWN, like chocolate brown, so I am not sure how much life the trans will have left in it, not sure if this is burned fluid or clutch residue from hard driving. I want it to last as long as possible but want to put the best/correct fluid in it.


Also, I think I will be doing a dry fill, so I will need 8.7qts of fluid correct? Does that include the torque converter? I will be draining the fluid from the torque converter and am not sure how much fluid needs to be put back in. For a dry fill do I take my dry trans and dry torque converter, put them together and then fill the trans with 8.7qts and let that fill the torque converter? (or would you pour fluid into the torque converter and then hook it up?)
 
#163 ·
Using T-IV is just a preference thing, tons of people say it works fine (and it does) and tons of other people will swear by sticking with the dexron stuff.

Dexron II is fine, III is better than II and compatible, and Dexron VI is backwards compatible with III and II (and much much better). If your fluid is that dirty I wouldn't put anything but II or III (or maybe T-IV) in it because the brand new (and better) fluid will scrape the inside of your trans clean and probably cause you more issues with all the junk floating around.

Unless you have the trans out and cleaned you aren't doing a dry fill. If you are, fill the torque converter as much as you can (it will be about halfway) and slide it on the input shaft. Fill the pan with 2-3 quarts and start the car, you'll have to add fluid after this point as the pump will suck fluid from the pan and fill the converter. Starting the car with the converter completely dry isn't recommended. Keep adding until the car moves in all gears and it reads up to the full mark on the dipstick when warm.
 
#165 · (Edited)
First post mentions clutches and discs in the transmissions, here's what I dug up (sources are http://kai.supramania.com/Supra/A340 Series Repair Manual (RM216).pdf and http://94supraturbos.synthasite.com/resources/95_TSRM_PDF_FILES/ATM Unit Repair.pdf):

A340E (behind the 7MGTE):
O/D Direct Clutch (C0).........2/2
Forward Clutch (C1)............5/5
Direct Clutch (C2)................4/4
2nd Brake (B2)....................5/5
1st & Reverse Brake (B3).....6/6
O/D Brake (B0)...................4/3

A340E (behind the 2JZGTE):
O/D Direct Clutch (C0)..........2/2
Forward Clutch (C1).............7/7
Direct Clutch (C2)................5/5
No.2 Brake (B2)...................5/5
1st and Reverse Brake (B3)...7/7
O/D Brake (B0)....................5/5


In drive, first gear, clutches engaged:..................C0, C1
In drive, second gear, clutches engaged:..............C0, C1, B2
In drive, third gear, clutches engaged:.................C0, C1, B2, C2
In drive, fourth gear, clutches engaged:...............C1, B2, C2, B0


For the life of me I can't find out what the clutches are for lock-up, because the above are for (well, I'd assume anyways) fourth gear not locked up. The guy I spoke to at atfspeed said WOT in 4th is fine if necessary, the trans shouldn't lock up in 4th at WOT anyways.
 
#167 ·
I have question about the factory temperature sensor I hope someone could enlighten me.

I'm replacing my BL tranny with an ATF and a custom FTI IP 4000 stall converter. I want to start monitoring tranny temps. So instead of installing a bunge in the pan for a temp sensor I was wondering if the feed coming out of the tranny with the factory temp sensor can be used? I realize this temp sensor is fed back to the ECU however I'm running a ProEFi and hoping to replace it with a Proefi temp sensor and connect to the ProEfi can gauge. I know the pan it probably more desirable but if the Toyota engineers design it that way why not use it.
 
#171 ·
i would highly highly recommend not using the AEM v1 with the stock transmission. some how when i installed the AEM to test it in my car, the shifts were like the car just got rear ended! the line pressure was sky high. unless its a boost logic or other upgraded unit (now i know whey they are breaking left and right on AEM machines). never found the work around to lower the pressure in the line, just had to upgrade to a th400.
 
#173 ·
I know your post was almost two months ago, but the rule is not to let the car shift into second gear while the tires are spinning as you might roll the 2nd gear sprag.

ATFSpeed sells an upgraded 2nd gear sprag. I believe the stock unit has a 22 element sprag (mine did, the MKIV transmissions might have a few more), and theirs is a 29 element sprag.
 
#174 ·
Glad this thread is back! So I'm still on The BL but afraid to really throw big numbers at it afraid it won't hold an break. I'm wanting to run Nitrous for launches how hard is that on the stock transmission? I'm thinking I'm going to jus throw what I can at the BL an it it breaks go with a ATF or C&C Motorsports has anyone Ran C&C tranny? They state there's is just as good enough better then ATF an have Ran there Stage 3 at 1200whp an haven't had any issues they don't really quite yet know the Capability of the Stage 3?
 
#176 ·
called toyota to get some T4 ATF for the supra and they kept telling me to get the dexron III fluid instead. wtf
 
#177 ·
Talk to someone else. Insist on the T4.
 
#185 ·
since this is the auto trans thread, how many of you would think the car would benefit from running well made all aluminum radiator with internal auto cooler in line with a filter an other external filters? or would you rather not have it connected to the rad at all.
 
#186 ·
Installed my auto trans temp on filter housing. Current routing transmission, external filter, trans cooler, back to trans. First time seeing auto trans data and surprised it takes 5+ minutes to crack 120'F and was in the 130-140 until parking/traffic speed where it went to 150s. Any issues with the slow warm up?
 
#187 ·
I've got a ATF Stage 3 built auto and was wondering if I can keep my OD on on the highway when doing a WOT pull or even at the dragstrip(which I haven't done yet).
 
#188 ·
No not recommended ...
 
#193 ·
Back with another question. So did a pull and maxed out at 133mph at 7200 rpm in 3rd gear on the highway in mexico. So I'm wondering is it safe to go into 4th(O/D) when trying to chase more speed once I'm at the top of 3rd? If so how? If not...what could I do to reach a higher top speed like what gearing would be appropriate? 3.27 gears? But also don't want to limit myself too much on acceleration as well. This car is an ATF built Stage 3 transmission as well if that makes a difference. Trying to learn as much as I can from you all with experience with this transmission.

Thanks.
 
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#194 ·
Back with another question. So did a pull and maxed out at 133mph at 7200 rpm in 3rd gear on the highway in mexico. So I'm wondering is it safe to go into 4th(O/D) when trying to chase more speed once I'm at the top of 3rd? If so how? If not...what could I do to reach a higher top speed like what gearing would be appropriate? 3.27 gears? But also don't want to limit myself too much on acceleration as well. This car is an ATF built Stage 3 transmission as well if that makes a difference. Trying to learn as much as I can from you all with experience with this transmission.

Thanks.
More RPM or a taller Tire will
Help increase MPH. You can also get a taller rear end gearing. That’s what I did I have a 3.13 rear end wjrh an auto trans. I think I’m good for 200mph.
 
#195 ·
Get a 28" tire, though the top end won't be as stable if you lower the tire pressures down. The best thing is to increase the rev limiter, if you can. If you're stock ECU, find a used G-Force ECU.

I wouldn't change the gearing - it will make the car a dog around town unless you're in boost. It will also mess with your shifting ie: the converter will unlock on the hwy at almost any throttle input. Even the tall tires will do that a little.

Al
 
#197 ·
Okay, so since the beginning, everyone has preached about using genuine Toyota T-IV trans fluid. But ATF recommends using Valvoline Dexron 6 fully synthetic fluid. Anyone running that fluid with good results? Notice any difference in performance from the T-IV? It's supposed to be thinner than the earlier Dexrons, presumably since it's synthetic.

I guess I will be making the switch since that is what they recommend, and they built the trans. Apparently, they use the Dexron 6 in all of their models of transmissions, and use the same clutches in all of them.

Damn, I got like 10 qts of the old T-IV, lol!

Al
 
#198 ·
I’ve always used Toyota’s T-IV in my ATF. Never had a problem with slipping making 900+ hp on a 4K stall for 3+ years. Use to own a boost logic ran T-IV in that for over 10 years making 500+ with no issues. Keep the fluid temps down and your golden. I’m not changing anything just because ATF uses something different. Toyota makes good shit.
 
#199 ·
That was my feeling last time I saw their Dexron 6 recommendation in the instructions, and I stuck with T-IV. But I burned up the clutches in the trans in a fairly short amount of time, so I decided to go with their recommendation after they rebuilt it. They said T-IV is technically okay, but that they recommended the Dex 6.

There has got to be a reason everyone else is having good luck with the ATF, and I am not. I had longevity with my old Level 10 trans, so I know how to make them live.

I'd bet the guy that ran 7.99 is running the Dex 6.

Al
 
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