Caring for the A340 Factory automatic trans / built or stock

[lithium14]

I'm back with more questions!!! I got the trans pan, now the oil pump from an is300, I have the part number here for the "body sub assy, front oil pump" 35301‑50020 for the a650e. Is this the correct part that will fit in my 1988 a340e?? lmk, thanks!!!

[XempH]

wait wait wait wait......your saying to race with the overdrive OFF.. meaning the button is pushed out? When I do pulls with it pushed out it feels like I have 80hp and get 0 pull, and when I leave the button pushed in and mash it I get the typical downshift of the car and insane pull. Explain.

[lithium14]

From what I understand, you are not supposed to be in OD for extended periods of time in WOT, rather, during a highway pull, you mash the pedal and let the trans downshift etc etc. And only if you are doing something like drag racing, where you may be in OD for quite some time, to leave OD off. I think.

Still need feedback on that part number... I have been searching frantically on SM and SF and can't find anything about the is300 oil pump...

[tissimo]

wait wait wait wait......your saying to race with the overdrive OFF.. meaning the button is pushed out? When I do pulls with it pushed out it feels like I have 80hp and get 0 pull, and when I leave the button pushed in and mash it I get the typical downshift of the car and insane pull. Explain.

what? are you in manual mode or something? it should act exactly the same but just have 3 gears vs 4. Still downshift when matted, and wont effect the hp at all. If you have manual mode on, it will stay in 3rd gear causing problems like you're saying.

WOT at all on the weak OD clutch can cause issues, its best just to leave it off at all times and not go into it at WOT.

[XempH]

no i'm not in manual mode but what you guys are saying makes no sense. when the button is pushed in O/D is on. that's what I drive around in all the time and my RPM isn't at 4k on the highway, but instead 2-2.5k. When im doing 40mph on the highway and press the O/D button, the button releases out and now you have O/D Off. If you do a pull from 40mph while O/D is off you get absolutely shit power because the trans does not downshift, instead your basically in 5th gear. From what I see O/D is 5th gear. I guess im doing it 'wrong' by never letting O/D be OFF (the button pushed out) and mashing the gas and letting the trans downshift and getting the most power out of it.

[tissimo]

Thats really odd. Mine downshifts fine with OD button out (OD off)

[XempH]

so when your doing 40mph and u press the O/D button your RPM doesn't jump to 4k?? Mashing the pedal with the O/D Off just makes the car pull from that speed, and feels completely weak. If you do a 40mph pull with O/D on (not pressed) the pull is great when you mash it because it will drop into 2nd, instead of staying in (from what I see) 5th gear.

[lithium14]

I don't think Supras ever came with a 5 speed auto... it's an a340e/a341 the second number is what number of gears it has. toyoto didn't come out with aX5X trans until afterwards. Correct me if I'm wrong. and if your trans isn't downshifting when OD is off, then something is wrong. with OD on, if you are in 4th on the highway (any speed over ~45mph) when you go WOT, it will kick down to 2nd. Once it gets to 4th your pull should be about done... so you can let off, then you will no longer be WOT, so all is good. When you turn OFF OD in 4th, the trans will downshift to 3rd, and when you go WOT it will still kick down to 2nd, but not shift up to 4th. at least this is how my trans behaves.

anyone know about that is300 oil pump compatibility?

[XempH]

^i understand that when you press OD it "downshifts" and becomes 4~k, but when you step on it I just get a small pull from 4 to 5 to 6 really fucking weak and slow. So i never use it.

[T6Rocket]

Third gear is not going to pull as hard as second gear, but it should still pull. Though not as much with stock twins as with a single. At 40 MPH it should downshift into second anyway.

There is a button under the gas pedal that is supposed to control downshifts under WOT, maybe you're not pressing the throttle far enough?

Al

[tissimo]

so when your doing 40mph and u press the O/D button your RPM doesn't jump to 4k?? Mashing the pedal with the O/D Off just makes the car pull from that speed, and feels completely weak. If you do a 40mph pull with O/D on (not pressed) the pull is great when you mash it because it will drop into 2nd, instead of staying in (from what I see) 5th gear.

RPMs will jump, only till like 2500-3k at 40mph though. When I floor it it'll downshift to 2nd and nail like 5500-6k and haul ass just like with OD on.

[binster]

With OD off the engine will be in a higher power band (rpms) and stay there during increased speeds. OD off basically takes you out of the 4th gear on the Auto (MKIV). Whenever we play on the highway I keep OD off. If I'm just cruising around then OD is on..

Thanks for writeup on the care of the Auto trans. I'm studying trans coolers now to keep my tranny alive as I do engine upgrades.

BK
94tt -

[XempH]

thanks for clarifying all. I'm still on the twins so when I go single in ~ a month i'll see about the O/D Off.

[Flicktitty]

i know this isn't a supra auto, but i thought it's bad to drive an auto like this?
At the 2:30 mark
http://www.youtube.com/watch?v=uq2GB...JV1sKQ&index=2

or will it just got hotter faster? Is there any issues with normal driving like this?

[reimundo]

So if you have your auto built for high hp can you have the o/d on?

[Justin777]

yes

[KevinB6876]

no i'm not in manual mode but what you guys are saying makes no sense. when the button is pushed in O/D is on. that's what I drive around in all the time and my RPM isn't at 4k on the highway, but instead 2-2.5k. When im doing 40mph on the highway and press the O/D button, the button releases out and now you have O/D Off. If you do a pull from 40mph while O/D is off you get absolutely shit power because the trans does not downshift, instead your basically in 5th gear. From what I see O/D is 5th gear. I guess im doing it 'wrong' by never letting O/D be OFF (the button pushed out) and mashing the gas and letting the trans downshift and getting the most power out of it.

5th gear huh?

That's interesting, since the Supra's automatic transmission is a 4 speed automatic. Having a "5th gear" in a 4 speed transmission has to be a first.

[KevinB6876]

so when your doing 40mph and u press the O/D button your RPM doesn't jump to 4k?? Mashing the pedal with the O/D Off just makes the car pull from that speed, and feels completely weak. If you do a 40mph pull with O/D on (not pressed) the pull is great when you mash it because it will drop into 2nd, instead of staying in (from what I see) 5th gear.

There is no 5th gear in the Supra's automatic.

[KevinB6876]

It would be nice if someone made a 5 speed or 6 speed automatic for the Supra that did not use an overdrive gear system for the final gear.

The A340 transmission is only a 3 speed with overdrive making it a 4 speed. But the 4th gear, being an overdrive gear, doesn't allow as much power to get to the wheels. Because it's an overdrive gear, it robs more power from the engine so that it puts less power to the wheels. I have confirmed this in testing.

[XempH]

^ if you read my other posts I put in quotes "5th gear" but forgot to there. I guess only my trans never downshifts if I mash it with O/D Off, just picks up from the 4k where its at.

[fmx81style]

Considering line pressure control amongst other things. Is it worth running a built auto and stall on a stock ecu/ piggyback setup. ?

[TJG]

How about some dialogue on how people run on the dyno? I know it's available via search, however as long as we are getting good info in one thread. . . .

The first time I dyno'd, I used the info from mkiv.com, however what concerns me is the end of the dyno run. Do you guys press the O/D button during the run so it shifts to 4th? Do you bounce off the rev limiter, then let off and let the dyno brake slow the car down in third gear? Manually push the gear shift to neutral?

[nolimits]

Just stop before the rev limit. When you hit the dyno brake it should immediately bring it down to speed. No reason to hit the rev limit. Definitely don't shift up (O/D off).

[nolimits]

Considering line pressure control amongst other things. Is it worth running a built auto and stall on a stock ecu/ piggyback setup. ?

stock ecu controls line pressures fine, so yes, it is worth running built w/stall. Piggyback won't alter that.

[Biologist]

Question when you change the fluids are you COMPLETELY flushing it out or just dropping the pan and filling it in? wouldn't it build Heat faster than usual? also Im racing on the Auto from a roll 40-140 and my speed limiter stopped at 135MPH. do i pull the TRAC fuse out? been searching all day and couldnt find a legit answer. also upgrading to a GS300 Trans Pan. thanks.

- Bio