PowerShift Transmission: Needs Replacing < 25,000km

[indiej]

A huge step to better understand the Powershift/SST

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The dual clutch Getrag TC-SST (Sportronic Shift Transmission) 6-speed, found in the EVO X, is a very compact and complex unit. We service them- please click HERE

To find a unit like this in a car that is not a $100K+ (P4,200K) exotic is very cool and us tech geeks love these things! For Mitsubishi to include the option to have them in the X shows how performance oriented the car really is.

Unfortunately, the SST unit is so complicated that very few people know how to repair them. Your average Mitsu tech, who is trained to work on an econo-box, won't have a clue and will just blindly replace the unit without ever cracking it open. On top of that, Getrag is notorious for pushing full replacement of the unit when it has a problem, and will not sell parts. This is becoming a serious problem for X owners now that their warranties are expiring. I can see why Getrag would do this. Due to the complexity of the unit, as a manufacturer, you don't want your average tech digging into them and try to fix them. In most cases, the unit may not function properly after the inexperienced tech performs repairs and quality is compromised. This is my guess as to how a company can keep quality up and control the repairs to their product to insure proper operation.

Luckily, we can repair these units and also upgrade them! We have access to all parts for repairs (sorry, we can't sell them yet. We can only use them for repairs here) and have a very solid experience with complex units like these due to our willingness to learn how they work and our engineering mentality.

The dealer usually wants to replace the unit for $12K (P508K), but we were able to repair the units pictured below for a small fraction of that price! These were the perfect units to take pictures of so we can show how it works, the weak links, and what can be done to increase reliability.

The clutch system is actually very simple in how it works. The system has 4 oil lines from the valve body which control pressure to the disks for clamping load and cooling.
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If you have a trans which is slipping, it could be a seal failure. We can replace these seals with new high temp units to prevent the failure from happening again if you wish to upgrade them.

Under these seals are the clutch packs. There are 4 friction disks for each clutch assembly. There can be up to 5 of them depending on the performance package you want.

We can install replacement clutch disks depending on your goals. There are types which have a more friction surface area and a way to fit 5 total disks into the assembly. Contact us if you need help in this area also.

The springs you see in the center of the hub are there to hold the clutch pack apart, when hydraulic pressure is taken away, to assure a full release from that clutch assembly. If the disks drag while the trans is trying to select a gear, it could ruin the synchros.
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Heat created by the clutch disks is also a known problem for the SST. One major complaint you hear about with dual clutch transmissions is how harsh they shift in city driving. A show called 'Gop Tear' has its hosts always complaining about how harsh they shift in slow city traffic. I personally don't understand this. If you buy a race car, how can you expect it to shift perfectly in hot city traffic? Due to this, it's my guess that the engineers for this SST trans tried to design this unit to shift very smoothly, so as to not have owners complain about the harshness of the shifting in the city. They did a great job! I was shocked when I felt the EVO SST for the first time. It felt like a total slush-box and didn't have the same quick engagement you feel through other vehicles with dual clutch systems. When in 'normal' mode, this trans could be mistaken for a real automatic with a torque converter. It doesn't feel like a dual clutch system at all! This is great for the person that wants an MR to feel like an econo-box, but this also causes many other problems.

The unfortunate side affect to smooth engagement of the clutches is it creates a lot of heat. When the clutches are in the 'friction zone' (the area where they are creating friction) they generate heat, and when you generate heat, you have wear and the unit is more prone to clutch and seal failure. It's like a driver in a manually shifted car riding the clutch everywhere they go. You will quickly burn up the clutch and kill it.

Overheating with the SST is a common annoyance, and a car which is supposed to be designed to run at the track will be forced to stop by an over-heating transmission in short time. The common fix for this is to install a high-end oil cooler, and pump system, so as to keep the fluid cool. This seems to work for most people, but I believe the over-heating issues is not caused by lack of cooling via the factory cooler, but too much friction, and slipping, through the disks. When at the track, the SST will not completely stop the heavy slipping of the disks when you change gears. Doing this repeatedly will eventually create so much heat that the factory cooling system can't keep up and the system shuts down to protect itself.

I believe the solution for the over-heating issue is to make the clutches switch and engage faster. The quicker the engagement, the less friction, which means less heat generated. Unfortunately, the faster the engagement, the harsher the shift around the city.

I can't imagine that the Getrag engineers were so stupid as to design a trans which over-heats so quickly. What I believe happened was they designed a unit which was supposed to engage quicker, which is why the cooling system for the unit is so small. When Mitsubishi noticed the complaints people had with the harsher shifting units in the exotics, the unit was already done and the engineers responsible for the programming of the unit had to make changes for smoother engagement. I believe there may have been a lack of communication between the electrical and the mechanical engineers during the development of this unit. The engineers which programmed the system to shift smoothly didn't take into account the fact that smooth shifting creates friction, which will over-heat the unit. I believe the over-heating issue is a programming problem in the ECU and can easily be repaired without the need for expensive oil cooler fixes.

I am trying to learn all I can about changing the way the trans shifts via reprogramming the system, but I am a bit weak in this area. If anyone out there has found a way to modify the shifting of this trans via the factory ECU, so it shifts from one clutch to the other more quickly, please let me know and I would be willing to possibly ship some units your way to try. I believe if the clutches are in the 'friction zone' for as little as possible that the clutches will live longer, seals will not fail, and the trans will not over-heat.

I do not want to change the quickness of the SST shifts by modifying the valve body. I believe doing that will make it shift harshly all of the time and the car will not be pleasant to drive at slow speeds. If we can modify the program, then we can keep the smooth city driving shifts and modify the high load/high RPM shifts so the customer can have the best of both Worlds.
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The whole article: SST How It Works, Problems, Upgrades &ndash; Jacks Transmissions LLC
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Ford, wake up

[sandakot]

just today our focus TDCi Sport 2011 (21000++km ODO) experienced engine and transmission malfunction. i tried restarting the engine, it work but the problem was still there. parang dumudulas yung clutch bigla tapos mag shoot-up yung rpm ko then i shift to neutral tapos okay nanaman. until a point where
transmission malfunction appeared on the OBD. i stopped and parked it at a gas station. tapos di na magstart ulit. then i had it towed back to Ford Libis. they will diagnose for the problems on wednesday.i am worried. i never experienced this problem with the car before and it was in tip top shape before this happened. i always use the manual mode and sport mode when overtaking. i am aware of the problems of the powershift transmission because i read threads about this car since i really love how it drives. kaya hindi narin ako nagulat nung nakita kong may transmission failure na. pero mas nabahala ako dun sa engine malfucntion but i wont be dwelling on it here since i think it's quite off topic.

anyways. yun lang muna masasabi ko since ngayon palang nangyari. I hope reprogramming would help para wala nang palitan para hindi na magtagal yung unit sa casa. any thoughts mga sir?

[ryanwilder]

Grabe mahal tumaga. Pano kayo yun bago ngaun, may park assist pa, pag nasira siguro module nun, baka 300k din lol kaya mas okey pa conventional eh. Kaya ako up to now, i dont own a car na touchscreen and i dont need intend to do so.

[3ple4]

just today our focus TDCi Sport 2011 (21000++km ODO) experienced engine and transmission.

Is the 2011 model same as the current model, yung bago ang design ng tail light?

[Kwisha]

just today our focus TDCi Sport 2011 (21000++km ODO) experienced engine and transmission malfunction. i tried restarting the engine, it work but the problem was still there. parang dumudulas yung clutch bigla tapos mag shoot-up yung rpm ko then i shift to neutral tapos okay nanaman. until a point where
transmission malfunction appeared on the OBD. i stopped and parked it at a gas station. tapos di na magstart ulit. then i had it towed back to Ford Libis. they will diagnose for the problems on wednesday.i am worried. i never experienced this problem with the car before and it was in tip top shape before this happened. i always use the manual mode and sport mode when overtaking. i am aware of the problems of the powershift transmission because i read threads about this car since i really love how it drives. kaya hindi narin ako nagulat nung nakita kong may transmission failure na. pero mas nabahala ako dun sa engine malfucntion but i wont be dwelling on it here since i think it's quite off topic.

anyways. yun lang muna masasabi ko since ngayon palang nangyari. I hope reprogramming would help para wala nang palitan para hindi na magtagal yung unit sa casa. any thoughts mga sir?

Sir, any update on the what happened to your car?

[basti08]

These are the cases why I strongly advocate "save the manuals"....

[sandakot]

Sir, any update on the what happened to your car?

the car is working fine now. they replaced the corrupted TCM with a new one all under warranty naman. sabi ng SA ko driver's fault daw yun. i tend to shift from M to D then to Sport mode whenever I overtake. in that way, the TCM is having a hard time on deciding which gear to choose and on how much power does the engine need to give whenever i do it. until the TCM suddenly gave up and ayun na-corrupt. then my SA told me to stick to one mode and avoid doing it again.
it took 1 and a half months to get our unit back. tagal ng process. diagnostics took 2weeks. approval of warranty, request for TCM and delivery was a 2weeks since imported from Thailand pa and another approval for installation. pero lesson learned. at least i get to drive it again. :D

[s10pao]

sabi ng SA ko driver's fault daw yun. i tend to shift from M to D then to Sport mode whenever I overtake. in that way, the TCM is having a hard time on deciding which gear to choose and on how much power does the engine need to give whenever i do it. until the TCM suddenly gave up and ayun na-corrupt. then my SA told me to stick to one mode and avoid doing it again.

sir parang BS ung explanation sayo nung SA. ung laman ng TCM/ECU ay source codes. kahit paulit ulit daanan ung lines of code na laman nun, nde dapat ma-corrupt un.

Sent from my GT-N7100 using Tapatalk 4 Beta

[sandakot]

sir parang BS ung explanation sayo nung SA. ung laman ng TCM/ECU ay source codes. kahit paulit ulit daanan ung lines of code na laman nun, nde dapat ma-corrupt un.

Sent from my GT-N7100 using Tapatalk 4 Beta

ganun po ba sir? feeling ko rin ganun eh. kasi my 1st SA told me na okay lang naman yung magshift ako ng mode while running kaya ginagawa ko siya. pero nagulat nga din ako nung yan yung explanation sakin ng SA ko ngayon. factory defect din naman daw ang dahilan kaya nagkaganun. ang labo lang talaga. ayaw pa aminin na may problems talaga with their powershift transmissions. ive seen a lot of threads here (particularly this thread) regarding transmission malfunctions kaya di nako nagulat nung nangyari sakin yun.

anyway, can you please kindly explain sir kung ano ba talaga ang meron sa TCM/ECU and ano yung function niya? TIA

[ghosthunter]

the car is working fine now. they replaced the corrupted TCM with a new one all under warranty naman. sabi ng SA ko driver's fault daw yun. i tend to shift from M to D then to Sport mode whenever I overtake. in that way, the TCM is having a hard time on deciding which gear to choose and on how much power does the engine need to give whenever i do it. until the TCM suddenly gave up and ayun na-corrupt. then my SA told me to stick to one mode and avoid doing it again.
it took 1 and a half months to get our unit back. tagal ng process. diagnostics took 2weeks. approval of warranty, request for TCM and delivery was a 2weeks since imported from Thailand pa and another approval for installation. pero lesson learned. at least i get to drive it again. :D

Sounds like the usual BS excuse to me where they blame the owner/driver for defects in their products.