Anyone else 3rd to 4th gear slip before engagement?
MBWorld Fanatic!
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From: Texas
10 C six trizzle
finally got the transmission apart for ya'll to see some stuff. Do not attempt this stuff at home without proper tools and manual. It's not hard for a professional but a diy should be considered out of the picture unless you want alot of frustration. I didnt show how to take it apart, not every little nut and bolt. This shouldnt be attempted. What im doing here is showing you some fried parts and a general idea of how these go together. All o-rings and torlon seals should be replaced, bearings inspected and soak all new clutch packs with friction material on them.
So first picture is the transmission all torn apart.
second picture shows the k1 clutch packs. They are only available as whole assembly.
third picture is the old k1's up close and burned up, they should look like a nice shiny machined surface with minor scapes or wear marks
fourth picture is the b1 clutch, it sits directly behind the bell housing of the transmission
fifth picture is the b1 clutches, nothing like the k1's but have some burn marks
sixth picture is the b3 going on top of b1, k1 goes inside b1.
So first picture is the transmission all torn apart.
second picture shows the k1 clutch packs. They are only available as whole assembly.
third picture is the old k1's up close and burned up, they should look like a nice shiny machined surface with minor scapes or wear marks
fourth picture is the b1 clutch, it sits directly behind the bell housing of the transmission
fifth picture is the b1 clutches, nothing like the k1's but have some burn marks
sixth picture is the b3 going on top of b1, k1 goes inside b1.
Last edited by roadtalontsi; Jun 18, 2014 at 10:24 PM.
MBWorld Fanatic!
Joined: Oct 2007
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From: Texas
10 C six trizzle
more pictures....
first picture b3 is installed not the position of that hole, i put the little feeder tube that goes from the valve body into it to show you why this is important.
second b1 and b3 installed with k1 sitting in the middle
third is the k2 clutch pack with front planetaries
fourth is how k2 sits installed on top of b1 and b3 etc....
fifth this is what brand new clutches look like before soaked in trans fluid, this is the k3 clutch also only available as a full assembly
sixth k3 and its friend part.
first picture b3 is installed not the position of that hole, i put the little feeder tube that goes from the valve body into it to show you why this is important.
second b1 and b3 installed with k1 sitting in the middle
third is the k2 clutch pack with front planetaries
fourth is how k2 sits installed on top of b1 and b3 etc....
fifth this is what brand new clutches look like before soaked in trans fluid, this is the k3 clutch also only available as a full assembly
sixth k3 and its friend part.
Last edited by roadtalontsi; Jun 18, 2014 at 10:23 PM.
MBWorld Fanatic!
Joined: Oct 2007
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From: Texas
10 C six trizzle
ok almost done here.
k3 installed in its friend
k3 and friend installed in rear planetary
and k3 and planetaries stacked ontop of everything
All the remaining parts like br and b3 are in the back of the transmission casing, i inspected them and they were all in good shape. bottom line is 540rwtq w/o valve body upgrade from weistec and lots of "abuse" or as id call driving a c63 properly equals new b1, k1,k2 and k3s. keep in mind my car came with the 700nm transmission, I believe most of the mct's came with 1000nm version
k3 installed in its friend
k3 and friend installed in rear planetary
and k3 and planetaries stacked ontop of everything
All the remaining parts like br and b3 are in the back of the transmission casing, i inspected them and they were all in good shape. bottom line is 540rwtq w/o valve body upgrade from weistec and lots of "abuse" or as id call driving a c63 properly equals new b1, k1,k2 and k3s. keep in mind my car came with the 700nm transmission, I believe most of the mct's came with 1000nm version
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2012 C63;1971 280SE 3.5(Sold);2023 EQS 450 SUV 4 Matic (Wife's)
Nice write up and pics. Did you use OEM or aftermarket performance clutch pacs? Don't know much about trans internals so the pics and info are much appreciated. 
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2017 Mini Cooper S Clubman ALL4 - British Racing Green
Do they even have aftermarket clutch packs for the 772.9 tranny in our car?
Also, what special tools did you use. Also.. some of us DIYers are a little more capable than others (not that I do not believe others are capable). Anyone willing to take on a transmission knows the risks, so you do not have to protect us
That said, is the manual you used the same one posted in the tranny fluid change thread somewhere? about 200 page document with a complete breakdown of the tranny. Not really a paint by numbers, but easy enough to assemble.
Also, what special tools did you use. Also.. some of us DIYers are a little more capable than others (not that I do not believe others are capable). Anyone willing to take on a transmission knows the risks, so you do not have to protect us
That said, is the manual you used the same one posted in the tranny fluid change thread somewhere? about 200 page document with a complete breakdown of the tranny. Not really a paint by numbers, but easy enough to assemble.
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From: Texas
10 C six trizzle
I used oem parts, i dont know of any after market stuff other than weistec upgrades. I would have done this but my wife's job situation has been up and down lately. Oh yea and everytime i said B2 it was actually B3 - im going to edit what i can above. i wrote this pretty late and i was tired. 
special tools are minimal just to replace clutches. basic torx set, torque wrench, snap ring plier set, some flat blade screw drivers, picks, depth micrometer, straight edge, and you'll need a big socket for the nut that holds the tail shaft in, its a special tool - its a big 12point deep socket that hollowed out to allow the shaft to go in deep. If you plan on going all out and replacing piston seals and stuff you'll need alot of special tools. All my gears shifted properly so no piston issues, just slippage under full load, not enough grip to hold all the torque. I used wis and prior schooling for instruction.
special tools are minimal just to replace clutches. basic torx set, torque wrench, snap ring plier set, some flat blade screw drivers, picks, depth micrometer, straight edge, and you'll need a big socket for the nut that holds the tail shaft in, its a special tool - its a big 12point deep socket that hollowed out to allow the shaft to go in deep. If you plan on going all out and replacing piston seals and stuff you'll need alot of special tools. All my gears shifted properly so no piston issues, just slippage under full load, not enough grip to hold all the torque. I used wis and prior schooling for instruction.
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From: San Jose area
'19 E63S sedan
What about cleanliness? I've worked on manual transmissions but have always been scared of touching an automatic because of this mental image of a tiny speck of something clogging a hydraulic passage. I guess you don't really need a cleanroom. But what kind of precautions do you take to avoid contamination?
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MBWorld Fanatic!
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From: Texas
10 C six trizzle
no clean room, you have to realize plenty of clutch material and debris comes off. Obviously try to stay clean but it's all under pressure and in most cases will flush out. You have to check your screens for the solenoids make sure they are clean. If the valvebody was opened thats where you have to be very clean, lots of small check *****, screens, springs, tight passages etc... If you can do a manual an auto isnt much harder if at all. Transmission fluid is a detergent and lubricant so it'll clean and lube everything, unlike manual splash and spray.
did it at my work, which is a shop
did it at my work, which is a shop
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Joined: Apr 2010
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2017 Mini Cooper S Clubman ALL4 - British Racing Green
special tools are minimal just to replace clutches. basic torx set, torque wrench, snap ring plier set, some flat blade screw drivers, picks, depth micrometer, straight edge, and you'll need a big socket for the nut that holds the tail shaft in, its a special tool - its a big 12point deep socket that hollowed out to allow the shaft to go in deep. If you plan on going all out and replacing piston seals and stuff you'll need alot of special tools. All my gears shifted properly so no piston issues, just slippage under full load, not enough grip to hold all the torque. I used wis and prior schooling for instruction.
Do you have a cost rundown of the parts list?
MBWorld Fanatic!
Joined: Oct 2007
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From: Texas
10 C six trizzle
MBWorld Fanatic!
Joined: Oct 2007
Posts: 2,296
Likes: 380
From: Texas
10 C six trizzle
so parts range about 20-40$ per clutch friction disc and steel disc, most of these have about 5-6 of each (depends on version etc...) + a thicker first and last steel. The whole k1 and k3 assembly run about 550-750$ they aren't available separately and must be ordered as a whole. You may also need different sized snap rings depending on what the clearances look like with the new parts.
here's a list of what clutches are used for each gear. typically the one that changes when engaging that gear is the problem. There is also the possibility of a solenoid getting clogged up or valve body issue too.
here's a list of what clutches are used for each gear. typically the one that changes when engaging that gear is the problem. There is also the possibility of a solenoid getting clogged up or valve body issue too.
MBWorld Fanatic!
Joined: Oct 2007
Posts: 2,296
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From: Texas
10 C six trizzle
I really dont know what they use. Considering they have their own cnc machines and manufacturing. Its quite possible they have some custom in house only parts that have additional clutches. The built transmission is actually a pretty good bargain, it's around the price of a new/remanufactured one from mb.
Thread Starter
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2010 C63 P30
So little update. Got the car diagnosed. They said they are going to pull the tranny and ship it out to get repaired. They think it is shift solenoids. Should be fixed in 1-2 weeks. They said 95% chance this should covered under my CPO warranty.
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From: Texas
10 C six trizzle
the dealership is sending the transmission out to get fixed? that's strange they aren't fixing it in house. I have no idea why it wouldnt be covered, maybe things are weird in canada with cpo warranty.
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From: Texas
10 C six trizzle
it's all back together now, im working on making the bigger transmission cooler fit behind the front grill in addition to the stock one too. My bumper is getting some repairs made also. So i driven it but a few 100 feet trouble free but not enough to get out of second gear. I'll report back and let ya'll know how the weistec valve body upgrade feels aswell.
I know theres been a few posts on this, but here is another incase ya'll missed out. This is the difference in the torque converter trans cooler and the mct. The one on the top is the power steering cooler, the middle is the transcooler for tq converter - which is about 2"-3" thick, the bottom is the much much larger - but only about 1" thick mct transmission cooler. They both have built in bypass thermostat which is nice. I dont really think i ever had issues with too much heat, but being in the south, daily driving, lots of extra power and the wife loves to hot lap the car when at the strip it cant hurt.
If you just wanted to make it directly fit the newer bigger one, you'd need a new radiator, condenser, mounting frame and some lines than what the older torque converter cars came with.
I know theres been a few posts on this, but here is another incase ya'll missed out. This is the difference in the torque converter trans cooler and the mct. The one on the top is the power steering cooler, the middle is the transcooler for tq converter - which is about 2"-3" thick, the bottom is the much much larger - but only about 1" thick mct transmission cooler. They both have built in bypass thermostat which is nice. I dont really think i ever had issues with too much heat, but being in the south, daily driving, lots of extra power and the wife loves to hot lap the car when at the strip it cant hurt.
If you just wanted to make it directly fit the newer bigger one, you'd need a new radiator, condenser, mounting frame and some lines than what the older torque converter cars came with.
Last edited by roadtalontsi; Jul 15, 2014 at 11:03 PM. Reason: picture automatically turned 90* renamed locations
Thread Starter
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2010 C63 P30
Update:
Car is FIXED!
-First thing they tried is swapping K2 and K3 solenoids. Did not fix it.
- Pulled tranny and sent to toronto. Replaced k1 clutch packs, rebuilt the torque converter. Couple of other things replaced also, dont have the full list of what happened there.
-Re-installed tranny. Problem still happening.
- Pulled tranny oil pan and replaced valve body. Put everything together and did adaptation procedure.
Everything good Covered by warranty.
Car shifting like new.
Car is FIXED!
-First thing they tried is swapping K2 and K3 solenoids. Did not fix it.
- Pulled tranny and sent to toronto. Replaced k1 clutch packs, rebuilt the torque converter. Couple of other things replaced also, dont have the full list of what happened there.
-Re-installed tranny. Problem still happening.
- Pulled tranny oil pan and replaced valve body. Put everything together and did adaptation procedure.
Everything good
Covered by warranty.Car shifting like new.
