06 Trans in an 04.5 LLY

millerman04

< The Man Cave
Jul 14, 2010
1,039
0
0
39
Clearville, Pa
Was wondering what all is required to do an 06 trans into an 04.5 LLY truck? My buddy can get a great deal on an 06 trans, and wanted to know what all needs to be done to make it work in his 04.5? Any help would be great!! Thanks!!
 

A_T_Ver

Member
Jul 31, 2007
416
0
16
I don't think you can do it and keep 6th gear. But then again i don't know much :D
 

THEFERMANATOR

LEGALLY INSANE
Feb 16, 2009
3,890
45
48
45
ZEPHYRHILLS, FL
Im thinkin he wanted the 6th gear kept. Now the fun begins right? :eek:

Tell him to call SUNCOAST then as the ONLY way to get 6th gear in an 01-05 truck is with the SUNCOAST TCM calibration(or somebody out there who has it as I know a few other tuners have it as well). Even then, you still need a modified 04-05 valve body as I don't know of any TCM calibration that will allow a 5 speed TCM to work with the 6 speeds lockup solonoid.
 

THEFERMANATOR

LEGALLY INSANE
Feb 16, 2009
3,890
45
48
45
ZEPHYRHILLS, FL
suncoasts website says it uses a 6 speed valve body mot a modified 5 speed

I don't see this on there site. http://www.suncoastconverters.com/shop/gm-allison-5-6-speed-conversion/#product-details And you can tell by looking at the pictured valve body it is a modified 5 speed 04-05 5 speed unit with the holes and 6th gear tube added. I have set a 04-05 5 speed and a 6 speed on the bench next to each other, and they are VERY simliar, but to make the 5 speed compatible lockup solonoid fuction requires using a modified 5 speed unit as the 6 speeds lockup solonoid bore is quite a bit different from a 5 speeds.