What is needed to make a 5-speed a 6-speed????

jboss

DIESEL JUNKIE
Mar 26, 2007
59
0
0
SoCal
is it just a stock tcm and valve body? I thought i read on tdp that is wasn't.
or was that just to push some product?
 

duratothemax

<--- slippery roads
Aug 28, 2006
7,139
10
0
Wyoming
Its a super custom secret TCM and suncoast's modified valve body that has a 6-speed pipe and g solenoid block off plate...

I dont see why an off the shelf 6-speed allison valve body wouldnt work tho....solenoids are wired a little differently, but then you can always run a 4th gen TCM ;)
 

Mike L.

Got Sheep?
Staff member
Vendor/Sponsor
Aug 12, 2006
15,686
232
63
Fullerton CA
Its a super custom secret TCM and suncoast's modified valve body that has a 6-speed pipe and g solenoid block off plate...

I dont see why an off the shelf 6-speed allison valve body wouldnt work tho....solenoids are wired a little differently, but then you can always run a 4th gen TCM ;)

There is an extra hole drilled in the G solenoid block off plate and 2 extra holes on the valve body plate.
 

jboss

DIESEL JUNKIE
Mar 26, 2007
59
0
0
SoCal
mike, the stock components can be modified to make a 6 speed?
i can get one cheap and would like to try it if it can be done.
 

turbo_bu

Member
Mar 27, 2007
193
6
18
Central IL
Is that why some people are trying to swap in the new TCM's? I believe that the new GMLAN is different than what was used on the older TCM's. But I believe that some people have also figured out another way to get them to talk.... Maybe something like the '96 Impala SS's ... [GM left in the OBD I stuff and they also talk OBD II, through another set of pins].