Chevy and GMC Duramax Diesel Forum banner

1 - 10 of 10 Posts

·
Registered
Joined
·
7 Posts
Discussion Starter #1
I've been seeing some ads for this Suncoast Allison A1000 5 speed to 6 speed conversion kit while researching drivetrain mods. Has anyone heard of someone who's done this and can speak to its integrity? I'm really interested to learn more about how this works and if it's a worthwhile investment. Apparently it is virtually plug n play besides TCM and valve body changes.

I'd be interested in this if I could determine it doesn't compromise any of Allison's superior awesomeness. Or anything else for that matter.

https://www.thoroughbreddiesel.com/2004-gmc-sierra-2500/a1-6vb-tcm-lb7/
 

·
Registered
Joined
·
103 Posts
I have no first hand knowledge, but I thought it sounded like a great idea years ago when it came out. It might be nice in some situations, like going 80 mph unloaded. If towing, you're not going to use 6th (and sometimes not even 5th) anyway. I can't remember anything in particular, but I'm under the impression that you don't get much of a boost in mpg.

But if you go 80 a lot and you don't like the high revs, it might be something to consider.
 

·
Registered
Joined
·
1,039 Posts
Duramax tuner has had their conversion kit out for atleast a year or two and I haven’t heard anything negative about it (besides the cost in my opinion). Really want to do it to my truck but just cant justify the almost 2k price tag. Installation looks simple enough


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
760 Posts
I know duramaxtuner does some stuff with the 5 to 6 speed conversion. I'd give them a call. Once you add some power to that Allison it is far from superior awesomeness i can assure ya of that.
 

·
Registered
Joined
·
7 Posts
Discussion Starter #5
The Suncoast one was north of $2k slightly and I agree that's a lot. Haven't read much on the duramaxtuner one. My truck is my daily driver and my commute is all interstate so I think it's reasonable to assume I could benefit from an extra gear. I do have an 8000lb boat so that's something to consider as well.

Definitely know about the Allison's kryptonite of a stronger power plant. A built trans is 2nd on my list of mods behind SAC injectors/studs/EFI Live.
 

·
Registered
Joined
·
1,039 Posts
I do believe that duramax tuner kit was under 2k but i cannot remember for sure off of the top of my head. Maybe i figured it was 2k with tax


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
476 Posts
The 5 and 6 speed tranny's all have the same hard parts. Spending $2k to pick up 0.25 mpg's will take forever to pay for itself.
its not always about the mpg's,,its about the lower noise inside the cabin.I actually sold a gentleman of the conversion while driving in my 02.over the phone he could hear the difference in engine noise.
 

·
Registered
Joined
·
476 Posts
I'd give socal a call,thats who I bought mine from.
 

·
Former GM Tech and parts
Joined
·
2,515 Posts
Ok, I'm going to chime in and you can listen to what I have to say or not. That's

This is not a new thing. Its like they are marketing it as the latest and greatest thing to do to your 5spd Allison, but its been out there for quite a while. I looked into it almost 10yrs ago when I built my trans the first time. The cost of doing the 6spd conversion makes it unreasonable. It will take you YEARS, maybe DECADES to recoup the money in fuel savings. Unless you just have double the money it takes to build the trans and you're just looking to throw that money away, its not worth it. Its not a cost-effective thing to do. There really isn't a benefit to it, because its not a big enough change in RPM to gain that much fuel mileage. Towing wont matter because unless you're running 90 down the interstate with a heavy load, which in itself is dumb and dangerous, you're not going to be in 6th gear anyway. And if you're driving unloaded, you're looking at like 400 rpm which isn't going to change your fuel usage much

Like I said, unless you just have screw off money that you want to throw away, it just doesn't pencil out. And if you do have that kind of money, I can find MUCH better ways to help you spend it... How about sponsoring a stock-appearing pulling truck? I have an opportunity for you if you'd like to do that :smile2:
 
1 - 10 of 10 Posts
Top