So I'm guessing that no one has done this, because it's just a little whacko.

But as my original CVT ages (72k miles currently), I grow more and more nervous each time I turn the key. Selling the car is not an option for me. So as far as I can see, I have two options:

1) Replace the CVT with another CVT when it goes (at a cost of $4-8k, depending on the dealer).

2) Replace the CVT with a different transmission (I'm thinking the 6-speed auto from the S).

I realize that option 2 is a little extreme, but I'm wondering if it's even possible...because it would sure be a lot more reliable.

Can we discuss?

 

I had someone ask me this exact same question last week... I don't think it's such a crazy idea... I think lots of folks will be thinking about this as the CVT failure rates are sure to increase...and the price isn't very different for a CVT and the Aisin.... but I'm not aware of anyone who has done it. I'm assuming that the transmission control is completely different between the two units... I don't know what the ECU integration issues would be... I've never compared the physical mounts, etc.... I know the difference in engine position and mounting between the MCS manual and auto... but don't know how this compares to the CVT justacoopers....

 

All the electronics "should" be contained in the TCM. Im thinking axles, trans, torque converter (if it has something like that). I havent done my homework on transaxle CVT's. Altho I did see some sort of clutch unit. Umm...TCM and possibly mount. I guess I could compare Cooper to MCS part numbers tomorrow. I have something to put her out of her misery Mel....

 

Yeah... if I had an hour to spend on RealOEM I could figure it out, I think...

 

please keep this post going and if you two that seem to know where to look could help me out in where to do my research i would love to help figure out if this swap is doable.

P.S. i'm the one that asked blimey a week ago.

 

My biggest concerns are electronics and the wiring harness... I doubt the harness is the same, I know the connectors on the CVT are different than the connectors on the Aisin. I also don't know if the different arrangement of the Cooper engine bay vs. the MCS would create any interference issues - I don't know how the physical size of the 2 trannies compare.

The schematics for the transmission mounts look the same, but the part numbers are different.

Controllers are different

Gearshift mechanisms look the same, but part numbers are different.

Engine wiring harness is a different part number (of course - cooper vs. MCS)

ECU is same part number (good sign!)

All this said... I'm still of the opinion that you'd spend less money selling your MC and buying a comparable MCS auto.

 

Again, selling is not going to happen. Not while I'm alive, anyway

So that's why I want to figure it out now, ahead of time, before it goes. I'm thinking if I can find a used Aisin with low miles (because mileage is less of an issue on the Aisins than the CVTs) I could have everything (parts and plans) ready to go before it happens so it can be a quick and relatively easy swap.

My big concerns, knowing nothing about what we'd be doing here, are the tranny to motor connection, the harness, and the TCM and ECU.

 

In reading my new Bentley Diagnosis book, it appears to have different programming for the CVT vs. the Aisin... so getting a flash for a Cooper with right bits for the Aisin might be the show stopper. While the ECU doesn't control the tranny directly, it DOES do most of the voodoo regarding gear ratios, etc. and tells the TCM what to do, the TCM just executes the mechanics of it... based on this... my vote is now "ain't gonna happen".

I think your viable options are:
1) get a spare CVT when you find one for the right price
2) find Clara2 - same car, but MCS.

Clara's a CVT.

 

So for people who did the 5-speed manual to 6-speed manual, did they have an ECU issue? Or is it not relevant to them because it's manual?

 

Not relevant... because their ECU isn't telling the tranny what to do...

 

I'd guess it would be cheaper to just buy another CVT when & if that time comes. I know it would be a heck of a lot easier. I'm not a believer in extended warranties, but it might pay in the long run for you.

 

Okay...so the autos are? They're not just deferring to the TCM?

 

Nope - they don't defer to the TCM... according to the Bentley Diagnosis book, the ECU does the "cypherin" to figure out what gear ratios are appropriate, when to upshift, etc. - then sends the instructions of WHAT to do it to the TCM which knows HOW to do that. And WHAT you'd want the transmission to do is different whether you have a CVT or a 6-speed auto... thus different ECU programming. But the only ECU flashes that know how to run the 6-speed auto are for an MCS.... which is quite different than the MC ECU - different sensors, different math, etc... (example: MCS ECU is looking for input from two MAP sensors, MC has only one).

 

hey if i get a 6 speed manual for $1,000 you think i could aquire the parts over time to swap my little beast into a manual and do it relativily cheap?

 

No. I don't think that will be practical. There's just too much that's different between the manual and the auto... a partial list:

ECU programming
Exhaust manifold/header
Engine and transmission mounts
Transmission
Clutch
Clutch pedal and all related linkage and hardware
Shifter and all related linkage and hardware
Intake tube
parts of wiring harness
...

 

k bummer. thanks for the input!