I spoke with Rudy on this issue after having problems with my TCU. The TCU from another SRT-6 will work in your SRT-6 "After" it has recieved a physical chip reset. This was only after trying 4 different SRT-6 TCU's in all three of my SRT-6 cars. All went limp without their own TCU installed.

32 Crazy - Your SLK appears to be somewhat different than the SRT's in my garage. I have also been working with Jerry resolving TCU issue over the past three months. He initially swapped my son and my TCU's while they were out of thier cases. When the incorrect TCU's were installed after the TCU mod, both cars went into limp mode. I am still working with Jerry to correct the TCU not holding gear and bouncing off the rev limiter issues. Jerry has explained that several TCU variations were available over the years causing inconsistancy in TCUs and TCU mod results.

Also, my cars will not upshift until they reach the correct RPM for the gear. If I am at 10MPH and select 5th the car will not upshift to 5th until the ECU/TCU agree that the car is at a safe speed. It will upshift through the gears as I achieve the next safe speed point.

 

not sure why there would be any differences. the entire driveline computers and suspension come right out of the discontinued slk32 amg's. i can swap parts with the srt and the part # are identical. the issue with yours could be the modded tcu's. perhaps theres a file that was messed with that caused the limp mode. i had latemodel21 (chris) ship me his oem tcu from his spare slk32 and it worked without any issues at all. reinstall my modded tcu and all my datalogg issues returned. i can easily swap the tcu with jhm2k new srt-6 and confirm the swapability or not when rob sends my thermalcoated intake parts back.

 

All that I can tell you is that I have tried 4 TCU's. 2 Modded and 2 stock in 3 different SRT-6's. The only configurations that worked were the original TCU from that car, and that the information that I recieved from Rudy and Jerry indicate that the Crossfire TCU is car/vin specific until physically chipped. Also, there is a difference between the original coding version of the EGS controller, one car is 2 versions changed from the other. This is appearently part of the problem with one of the SRT-6's not accepting the full TCU mod.

 

rob texted me today that my parts should be done monday. hopefully i will get them before the holiday weekend and have my v2 tcu back in for datalogg. over the weekend ill swap jhm2k's tcu into my car and see what happens. ill let you know

 

I bought mine a little over a year ago for about $18,000 with 16k miles. I think you could do better. Although the trend these days with Crossfire sellers is to jack up the price due to the rising rarity of the car.