Engine Drivetrain 1st Gen Cooper S Most liked posts in thread: The Automatic Transmission Rebuild Thread

Blimey/Paul

Great write up, I have a feeling this is in my future also, so I have book marked and download all the info. My only question, is now that I have seen inside the trans, does anyone make a limit slip diff for this trans?

I would love to swap mine out when I do have to go inside.

C0op3r

 

Wow great work Paul.

 

Boy is this thread timely. We're at a crossroads with the wife's 05 MCSa as the transmissions been acting up lately.

 

When hot, hard shifting, and or shift hesitating

 

Transmichigan, I like that!

A mechanic friend calls them transmixers.

 

WOW, What a nice write-up. Even makes me think I could almost do it with the details. Could / Would - Different [emoji16] Great job! Glad Blimey is feeling better now, hope he can come to MSSD and play with his friends! [emoji3]

 

I'm new to this forum. I've got an R53 Aisin with 140k. I did several fluid exchanges on my car last week, both for preventative maintenance and potentially resolving a very occasional shift flare in 1-2-3 range. Since doing that, the transmission has become remarkably worse, especially when cold. If I don't let off the gas when the engine sounds like it wants to shift (3k RPM or so) it slams HARD.

I've driven several hundred miles in hopes the TCM would readapt, but no such luck! I've checked the fluid levels 3x. I don't believe it's either over or underfilled, though I don't have an IR thermometer, but I put the same amount in that I took out initially. I then slowly added more warmed fluid after the car had idled until it poured out over the stand pipe and out the drain.

I feel like the next logical step is going to be a Revmax valve body. I don't have the $1,000 for part + core. What goes into rebuilding a valve body. Aren't the solenoids the primary failure cause? Can these be bought somewhere and replaced DIY on my core? I've only got about $300 I can throw at this car during the holiday season.

 

Look forward to your update... the car, and you. Good luck with your surgery. I have some coming too, and hope to get it out of the way before Christmas. With the VA it's a toss up.

 

Hey Paul,

I have been reading a lot of your posts both here as well as the "other" site regarding your transmission issues. I am having a small amount of trouble with my Fiance's transmission in her 2005 mcs. And have been considering the vavle body replacement for the second time on the car. However I am a very confident mechanic and have also tossed around the idea of just starting fresh.

i.e. buying the revmax valvebody, as well as the sonnax pinned sleeve, and a total overhaul kit and just starting over. With everything new. However I was curious to see how your transmission ended up after the overhaul? I have not seen a post where you finished it with any update as of yet. I would love to know that your unit works just like new after the work and there are no suprises for a potential DIY'er like myself.

I also saw you mentioned that you had an upcoming surgery. I hope there were no issues with that that have been the delay in updates.

Hope all is well and look forward to hearing how everything went.

 

Welcome to M/A!

On the subject of automatic trannys, I was having shifting issues with my '06 MCSa. The dealer told me it was going out so I took it to a shop that works on a lot of MINIs. They analyzed it and replaced the tranny fluid. The shifting problem has disappeared. That was about 2,000 miles ago. The car now has just under 104,000 miles. I had bought the car new and had done all the Service 2 checks, but the other mechanic told me that perhaps the tranny fluid had not been recently changed [if at all] since new as BMW likes to think of it as permanent.

So, before tearing the tranny apart, check the fluid first. If it is cruddy, like mine was, change it and see if that resolves your problems.

 

Great to see you back and healthy once again! Congrats!

 

Originally I wasnt trying to clutter up Blimey's thread with my information. So I held this back. But I will give you a quick history on the car. It is a 2005 MCS auto. Originally purchased by a close friend of mine for his mother to drive. They kept good care of the car and about 2 years ago the transmission started shifting very hard and acting stupid. First he took it to Global Mini here in Atlanta and they told him "no problem, just give us $9700.00 and we will install a new transmission." So he called me and we went through options. We found a guy local here "very small shop" that has done quite a few mini valve bodies with good success. He told us that the VB solves 90% of the transmissions. But he would like to install one first and see how it went before removing the unit.

He installed a generic remanufactured valve body and sent the car home. it has been running fine for some time now.

I purchased the car from him 5 months ago for my fiance to drive. Her jeep was laid to rest by a texting driver.

Since we have owned it I have started to notice a few signs intermittently of trans problems. Once again all of it "so far" is intermittent and doesnt all happen at the same time. On cold starts it will occasionally hang in second until about 4500 rpms leaving the driveway. I have seen it flair shift from second to third three times now about 2 to 400 rpms before it moves on. And probably the most noticeable and often occurance is that it seems to shift early out of first and second. Leaving it at a really low rpm in third to make any torque. Havent noticed anything yet in 4-5-6. Seems normal. Also I think its worth noting that it shifts buttery smooth. I havent noticed a hard shift at all either up or down.

Given the data that I am accumulating I am researching what plan of action I should take. As I stated before I am a master technician, and I am not scared to go through the unit if I have to. However I would prefer not to if its not necessary.

Lets hear some thoughts from you guys. I always want more opinions so feel free, good or bad.

 

Great article, I have done engine work, but automatic transmissions just look like a lot of potential for error with limited time I have to do the work. My wife's 2005 MCSa started having problems @ 93K - of course if I had bothered to have the fluid changed it may have lasted longer. Had the transmission rebuilt and new converter and it has been running and shifting good as new for 5K miles - no leaks. Ended up costing me about $2.5K, better than buying a new car. Mini dealer quoted $5-6K for new transmission and $4-5K to install.