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Old 05-25-2017, 04:40 AM   #11
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I do remember a few Forum members that have had their manual transmission replaced due to bearing failure. Repairing wasn't an option; the whole assembly was replaced. I have a theory about the cause of failure. Because the transmission is marginal for its horsepower/torque application, it experiences excessive loads on the gear shaft bearings. Conditions that would exacerbate this problem would be: Operating in too high a gear ratio for a given road speed/load. I perceive that many lesser experienced drivers are too eager to select top gear, and apply excessive throttle as their normal method of operation. This, along with added power from a tune, places extreme loads on the transmission gears and bearings, creating excessive heat. If the proper gear is selected, the vehicle will accelerate readily with moderate throttle application. If operated in this manner, the transmission will not see excessive bearing and gear loading, and thus not develop excessive heat and wear. As I drive, I am conscious of the loads I am placing on the drive train, and operate the vehicle accordingly. Hopefully this will increase the longevity of my transmission.
Getting back on topic, a high performance breather cannot hurt, but I believe how the vehicle is operated is a bigger factor.
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Old 05-25-2017, 01:16 PM   #12
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I don't disagree with that at all Papasonic. These shops that will explained the heat issue to me are not no name places though, MFactory designed and sells their own LSD for the M32. Some of us are not inexperienced drivers, we know how to shift and the limits of synchros. I've driven a dozen or so for dailys not including industrial non-synchroed ones, getrag, multiple NVs, T5, T56, TR6060, Hondas, now an Isuzu. The getrag, NV4500, and T5 I built myself. The only one that had difficulty shifting at high rpm like the M32 were the NV3500s, I imagine it was at the power or rpm limit of the synchros like you say, slowing down the shifts at lower rpm that one shifted fine. None of them ran hot like the M32 and worked noticeably better after cooling.
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Old 05-25-2017, 01:55 PM   #13
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I really don't think that heat is a big problem here in the US, we dont drive at high speeds shifting for long periods of time. If your worried about heat build a cooler system with small pump-tap into drain, then back in the top of trans.
Now the big bearing conversion looks like a good mod, but will require complete disassembly to press bearings. I think most of the issues come from speed shifting. There is a transmission shop that does honda transmissions and they coat the synros & hubs with carbon fiber to help them mesh at high rpm, been doing it a while for racing. I talked to them but they were not interested in the M32. And as a second note parts for M32 in the US are very hard to come by, GM doesn't want to work on them- just remove and replace.
Just my 2 cents. greg
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Old 05-25-2017, 02:55 PM   #14
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Quote:
Originally Posted by TheGreenDragon View Post
Couldn't I just go full JDM instead with a massive front-mount oil cooler?
The only solution:
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Old 05-25-2017, 03:01 PM   #15
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Tormach, yes I think the cooler is a good idea for people who track their cars. For the rest who don't granny shift 99% of the time, there are other solutions.

Part of me wonders if the 2012-2013 modification of removing the underbody tray on the Sonic had something to do with keeping the trans cooler - GM replaced so many in the cruze/sonic from '11-'13. & the few instances of engine bay fires they had, seems like a good cost cutting move to not use the tray.
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Old 05-25-2017, 03:19 PM   #16
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Quote:
Originally Posted by greg51 View Post
I really don't think that heat is a big problem here in the US, we dont drive at high speeds shifting for long periods of time. If your worried about heat build a cooler system with small pump-tap into drain, then back in the top of trans.
Now the big bearing conversion looks like a good mod, but will require complete disassembly to press bearings. I think most of the issues come from speed shifting. There is a transmission shop that does honda transmissions and they coat the synros & hubs with carbon fiber to help them mesh at high rpm, been doing it a while for racing. I talked to them but they were not interested in the M32. And as a second note parts for M32 in the US are very hard to come by, GM doesn't want to work on them- just remove and replace.
Just my 2 cents. greg
I don't think it's a huge problem either, usually it shifts just fine. When it heats up and locks up, people try to shift it instead of letting it cool a few hours. Then we hear about the gear grinding issues.

Warrington Transmission Centre in the UK has been great with getting a pile of stock M32 parts, shipping takes a while but the prices aren't outrageous. They're all clean and look like they've been blasted.

I'm pretty sure WG Motorworks could upgrade the synchros if that's the issue, but I don't think it is. I've not had a problem with the RPM of the shift, generally it's a random.. lock up/cant shift/grinding issue(not from missing shift)..

The trans cooler is overkill, but not a bad idea. I think more to the point if the bearings were supplied with oil directly, that would be better than a simple trans cooler. If installing a pump, both could be done simultaneously.

There are aluminum fins with heat sink tape that would help with the overheating issue, and they're simple.
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Old 05-25-2017, 05:28 PM   #17
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Quote:
Originally Posted by mja View Post
The only solution:
I like the look of that car (funny.. i think the cooler lines could double as a tow hook) .. especially those forward mounted mirrors.
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Old 05-25-2017, 05:45 PM   #18
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It's a gorgeous old Celica, those lines though lol. Agreed, someone should tow it from them
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Old 08-11-2017, 11:58 PM   #19
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I saw a nipple on the auto trans. Do they have a breather tube that goes on there like the manual trans? I feel it gets dirty in there or when i hit a big puddle water gets in.
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Old 08-15-2017, 06:38 AM   #20
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The automatic has a black screw-on cap on the fill port which is right under the ECM/Battery tray. It doubles as the breather.
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