Thanks for the detailed response cristo!
I'm working on a tight budget and getting a used trans so I'm assuming I'll need all the parts you had leftover. None of them seem too expensive and of course I'd rather have them and not need them.

Just ordered my first batch of parts (the small stuff) and I'm rather excited to get moving on this project.

 

Would you recommend it for daily driving in some traffic? The 35lbs of the valeo flywheel just seems like a lot of extra weight to be saddling on.

 

I drove it in rush hour traffic as my daily, worked fine for that

 

Might as well keep this thread going... lol

2002 Mini Cooper r50
139K miles
Midlands transmission failure.

My brother-in-law bought the car used @ 80k, so its uncertain whether this is the first failure (which... 140k isn't bad for a midlands, I guess) or if it has happened before. The transmission had a "tested" sticker on it when removed, so I'm not sure if that has any significance.

I'm rebuilding the transmission myself, so I got to look first hand at what failed. Much to my dismay, I found multiple failures.

*Reverse gear heavily worn, a few teeth chipped.
*Input shaft gears (reverse & the one closest to the input shaft bearing) both chipped.
*One of the gears on the countershaft was also chipped. I believe it was 1st gear.

The transmission continued to function with all of those failures. By some miracle, the metal from the chipped teeth didn't make their way into anything critical... at least not to the point of blowing any holes in the case, etc.

The ultimate failure that stopped the car was actually the ring gear spinning free from the differential housing. The symptoms on the car were very strange to me but now make sense. With no load on the front wheels they would turn fine in any gear. When putting load on the wheels however, it would not move in any gear. In addition, rotating one axle would not cause the alternate axle to counter-rotate.

After doing a little research, it looks like the ring gear is simply pressed onto the differential housing?? Seems like a terrible idea. Has anyone here welded the assembly together? Is there any aftermarket differential that features a bolt-on ring gear? I haven't found anything, but I'm sure someone has tried to improve upon this, even if there is nothing commercially available.

My current plan is to rebuild the transmission with a kit from eBay, which should take care of all the gear issues and give it some new bearings. I also think I'm going to weld the ring gear onto the differential assembly. If anyone has any thoughts on this... let me know (pros/cons).

I should consider myself very lucky. With the chipped gears and metal floating around in the transmission, the ring gear popping free probably saved the transmission from further damage/destruction. That's really my only concern with welding it together. Sometimes you fix a weak spot which only makes something else upstream fail... possibly in a more catastrophic way.

Anyway, that's my experience. I'll try to get some pics for reference.
Add me to the midlands failure guestbook... haha.

We should get T-shirts or something.

 

My 2003 196,400.00 miles
City and Highway - drive it fun.
Just replaced the original transmission / clutch and axles (2nd set of axles and clutch)
Bought a Midlands rebuilt here in Greenville,SC and had it installed in Wilmington,NC as that is where the MINI stopped working...

 

My Midlands I still going strong! Just drove over 113k and shifts are a little tight, but the car is driving as well as it ever has.

I have decided that when it does go, I will replace it with a new Midlands transmission. I am sure that now my car is off daily duty, this should last for quite some time.

 

I have the Getrag 6-speed In my 2002 MC and love it!

 

Hi guys,

My 02 R50 Cooper is on about 104k miles, and sometimes the 'box is stiff whilst getting into reverse, meaning I have to jiggle it around other gears for it to eventually settle.

The 'box hasn't had any modifications or work done to it since new as far as I'm aware, so my question is should I be worried about a potentially large bill? And how large could this bill be?

I'm in the UK if that helps any responses.

 

Mine just went at 173k. 2nd gear synchro was pretty worn but a spun ring gear was what took it out. Shame on BMW for such a cheap design. I found a guy in New York that sold me the parts to fix it but I will be looking to do a Getrag swap long term.

 

Mine died with about 122k. Was rebuilt. Seems as fine as is was before it died, which is not saying much.

 

Good day all

I decided to replace all of the bearings before self destruction occurred. Both diff bearings, both input shaft and both output shaft bearings replaced. I'm at the point where I'm torquing the shaft nuts. When I torque the output shaft nut to spec (95 ft lbs) the input shaft is extremely hard to rotate. Also the gears will not engage. Has anyone else had this problem?