Hi Everyone. New to the forums.

Has anyone documented their process of actually rebuilding the SST transmission? (i.e. as a solution for several of the TC-SST problems raised in this sub-forum)

With the transmission approaching its warranty expiration, I just wanted to know what others had done. Particularly, things to consider when performing such a rebuild. Pics taken during the process would be a ton of help.

Thanks in advance.

 

The only things I have seen people replace are the clutches. The tranny is pretty durable, even when running 500+ hp.

 

Depends on the issue but the seals, torque dampner springs, and shims can all be upgraded and replaced based on the issue at hand along with the clutchpacks of course. We recently sent out a Dr. Seto's SST trans to SSP Texas and Jeremy did the clutchpack upgrade along with the new seals and re-shimmed it all properly. Said it was setup wrong from the factory which would explain the slightly sloppier shifting feel it had compared to my brand new 2011.

In a drag racing setting you might see more abuse but for road racing or daily driving the transmission is quite durable if you keep the temps in check and avoid causing the clutchpacks to slip excessively.

 

Thank you for the responses.

My intention was only for rebuilding for DD/occasional track purposes and not for drag racing.

I'm surprised that the SST was setup wrong from the factory for some units. How can someone tell that the setup was wrong? (other than the shifting feel when driving)

Can we not get back at / Getrag for such errors?

Thanks again.

 

By measuring during dis-assembly.

 

Are there any other common failure items in the SST? I would like to keep the car after the warranty expires, but can't see spending a $9k on a new tranny if it fails.

 

The consensus is keep it cool, change the fluids often and upgrade the clutches if you need more torque. There's not that much that can be done.

 

One of the mechanics on the australia evo forum said Mitsubishi is now adding part numbers for SST parts/sensors into their parts catalog so it looks like the SST will become a serviceable/fixable item. So no more dumping 10k on a full unit if something goes wrong.

Thats as much info as I know though.

 

We can get new mechatronic assemblies from Mitsu. The temp sensor that fails, and the TCU are part of this assembly.

As for rebuilding them..

I put an Evo gear set into an SST case and had it work when I was done. None of the internal rotating parts are currently available from Mitsu/Getrag, so I save them all from used/wrecked transmissions.

 

Update: I got the transmission rebuilt and the shifting through gears seems much better now. New clutch (stock) packs were installed.

However now I am experiencing a different kind of problem. I notice that, when on the highway driving at Normal, upon boost, the revs would spike and then suddenly the transmission stops engaging (i.e. no response when I step on the gas, as if the clutch was open on a manual.) The gears seem to go out of whack as well. I think the ECU is trying to rev match for the proper gear, but fails...

I tried using the paddle shifters, but still no response. I literally had to stop on the side of the road, turn off the car and restart it, then the tranny started shifting normally again. This can get pretty scary if on a highway at night with cars speeding and you are slowing down...

Could anyone possibly provide their inputs as to what may still be going on? Would there be a failsafe / trigger where the ECU triggers the engine not to engage the tranny upon boost?

Thanks in advance.

 

who did you get it rebuilt from?

 

Maybe get a dealer to (re)run the SST "learn-in" operations...

Rich

 

This. It's been 8 days.