Question about the A Series Transmissions...
- Thread starter Kai
- Start date
It's a common misconception!
Always laugh at the genius's that lock the cable full on thinking it's better in some way
Always laugh at the genius's that lock the cable full on thinking it's better in some way
The input spline is different than the A340, the A650 5-spd is 20 spline.
And the length of the torque converter is different, I believe.
So you may have to adapt the Lexus converter some how.
I had to get a custom converter built so that I can use the IS300 OD assembly in my A340.
And the length of the torque converter is different, I believe.
So you may have to adapt the Lexus converter some how.
I had to get a custom converter built so that I can use the IS300 OD assembly in my A340.
Hmm...any way of replacing the spline on the torque converter, such as a hydraulic press? There was a swedish guy that did that with a triple plate clutch he bought - replaced the spline to work on the R154.
More than likely the distance from the pilot on the TC to the mounting pads is about the same as there's quite a bit of room on the shafts, I have a couple of TC's here that are totally different body dimensions but the above two points are the same.
R154 | | 3.251 | 1.955 | 1.310 | 1.00 | 0.753 | 3.180
A340E | | 2.804 | 1.531 | 1.00 | 0.705 | | 2.393
A350E | | 2.804 | 1.978 | 1.531 | 1.00 | 0.705 | 2.393
A650E | | 3.357 | 2.180 | 1.424 | 1.00 | 0.753 | 3.266
Looking at that table, the A650E looks like it's a close match for the R154 in terms of gearing - so surely the 3.73:1 diff would be okay to use?
With an auto you want a bit deeper gearing to make full use of the torque multiplication from the converter, you'd also be raising the cruising RPM so economy will suffer, the 650 with it's low 1st can give you the best of both worlds if you use the right diff ratio.
If not may as well stay with the 340 as it will be far cheaper in the long run.
If not may as well stay with the 340 as it will be far cheaper in the long run.
Aaah, right, i think i know what you're getting at - sorry for asking so many questions, but trying to learn something here
With the ratio's tabled above, would there be any benefit to an A350E over an A340?
With the ratio's tabled above, would there be any benefit to an A350E over an A340?
Managed to get hold of some A340E's that are working, but tired - this should give me some practical experiences with working with slushboxes...
Kai;1479700 said:
About the only thing difficult in them is getting large enough snap-ring pliers to work on them.
That, and the Toyota manual is not quite detailed enough for my liking,
so I picked up several other manuals, and between all 3 or 4 of them, I found all the info I was after, like fluid circuit diagrams.
The A340s are used in several brands of cars, like Volvo, and Isuzu,
so parts are easy to find.
A local transmision supply house here had all sorts of different thickness plates for the clutch packs,
so it made converting the non-turbo A340 to take extra plates quite simple.
In slushboxes - is it usually the brake bands/clutch packs that wear out and fail, or the hydraulics/solenoids?
Typically if they are slipping for a long time, the band & plates are toast.
If you catch the early, many times it's a dirty filter screen.
A filter change & fresh fluid has cured several of mine that were acting up.
If a solenoid fails, it will just not shift propperly.
All solenoids inop, the car will want to start off in overdrive.
If the trans has been run a long time with old fluid, and/or the filter screen has been damaged by some former grease monkey working on it,
the spools in the valve body can get scored up, and stick.
I manged to get home from a cross country trip, by scotch briting the spools up on just such a trans.
When I pulled the pan off, I found that the filter screen had been ripped by the dumb as at the big name, nation wide trans shop that the former owner had taken it to just prior to me buying the car.
It worked fine to get me home, but I trashed and dropped in a 5-speed.
If you catch the early, many times it's a dirty filter screen.
A filter change & fresh fluid has cured several of mine that were acting up.
If a solenoid fails, it will just not shift propperly.
All solenoids inop, the car will want to start off in overdrive.
If the trans has been run a long time with old fluid, and/or the filter screen has been damaged by some former grease monkey working on it,
the spools in the valve body can get scored up, and stick.
I manged to get home from a cross country trip, by scotch briting the spools up on just such a trans.
When I pulled the pan off, I found that the filter screen had been ripped by the dumb as at the big name, nation wide trans shop that the former owner had taken it to just prior to me buying the car.
It worked fine to get me home, but I trashed and dropped in a 5-speed.
Well, my IS300 OD swap just became reality.
I just wish I had kept the IS trans, instead of sending it to the scrap yard.
I had checked when I pulled the OD assembly out of the IS trans, that the A340e OD slid in with no issues,
and the higher flow IS pump assembly was dimensionally the same.
Never thought about the IS OD assy being larger in diameter.............
It hit the overdrive brake piston, OD brake spring assy, and the OD support.
All of them, plus the OD planetary ring gear needed machine work to fit together.
I am sure that if I had keept those pieces from the IS tranny, the job would have been much easier.......
Or better yet, if I could have just found an A340e from Japan, that had the .75 OD ratio in the first place
But it is in now, and just waiting for a fresh filter to show up (and to get the engine put back together),
and it will be ready for a test.
I just wish I had kept the IS trans, instead of sending it to the scrap yard.
I had checked when I pulled the OD assembly out of the IS trans, that the A340e OD slid in with no issues,
and the higher flow IS pump assembly was dimensionally the same.
Never thought about the IS OD assy being larger in diameter.............
It hit the overdrive brake piston, OD brake spring assy, and the OD support.
All of them, plus the OD planetary ring gear needed machine work to fit together.
I am sure that if I had keept those pieces from the IS tranny, the job would have been much easier.......
Or better yet, if I could have just found an A340e from Japan, that had the .75 OD ratio in the first place
But it is in now, and just waiting for a fresh filter to show up (and to get the engine put back together),
and it will be ready for a test.
Ian - stumbled across this in my never ending geeky tech search: http://www.supraforums.com/forum/showthread.php?t=267655&page=1
Yes, i know the source...but still
Yes, i know the source...but still
Covers all the basics nicely Kai but it assumes the trans is in good condition to begin with, no sense in doing all the pressure mods on a tired box, also don't agree with the line pressure cable mod that was posted in there if it's still there, makes 0 sense.