A 2004 lb7 GMC 2500 crew cab short box has just come into my possession, before I got it the front differential didn't disengage and blew the u-joint in between the front driveshaft and the t-case. That sent the driveshaft flying around and it smashed the trans at 120 kph breaking the shift linkage off and putting a hole in the transmission case behind where the shift linkage is. I want to know if it is possible to put a 6 speed Allison from a newer Duramax and what any problems I would have because I've been searching for a while and haven't found anything on putting a 6 speed into an lb7 truck or any other truck that had a 5 speed for that matter. anything would be helpful, thanks
From what I have read, your 2004 Alison is already a 6 speed. you just have to buy the conversion valve body along with getting the Transmission control module remapped. i'd say it's a 2500 to 3000 upgrade but the trans itself already has the gears!
Yes but the trans or atleast the case is Broken and I’m looking for a new transmission for it and can’t seem to find one for the specific truck I have so I was wondering about putting a newer trans because there easier to find
From what i have read, they are the same transmission. However, you would most certainly have to get the TCM reflashed. Just search 5 to 6 speed conversion and you'll find all the info you need. it will be my next upgrade after i sort out the fuel in my oil!
I'm quite positive that if he was able to rebuild his LB7 trans and then install the upgraded valve body and then have his LB7 TCM reflashed, he would have his 6 speed Allison. just sayin, no expert here...
67msarg3... I was answering the OP's specific question (see above)...
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Related Threads
?
?
?
?
?
Chevy and GMC Duramax Diesel Forum
3.8M posts
206.6K members
Since 2005
A forum community dedicated to Chevy and GMC Duramax diesel owners and enthusiasts. Come join the discussion about modifications, towing, classifieds, troubleshooting, maintenance, and more!