[dmac]

I had a 8.1 liter 2006 Chevy truck with a 6 speed Allison transmission. I know I could cut up the tunnel to make it fit, and it would last forever. I can pick one up pretty cheap- less than $1000. Read about eliminating the need for computer control on some other transmissions. Is this a really stupid idea to get a six-speed tranny in the car?

[lust4speed]

Besides size, aren't they really heavy?

[Will]

Are you sure you'd be able to eliminate the computer control? It's just that easy?

[Sirrotica]

Seems to me if you wanted a 6 speed, a 6L80E would fit better, but they are ECM controlled and usually expensive too.

One other question, why is it imperative to eliminate the ECM?

Upon some quick searching online I see no way you'd be able to eliminate the ECM. The case is huge on those transmissions, seems a little impracticle to install one in a car when a 4L80E or a 6L80E would fit much easier.

[HWYSTR455]

I have yet to see any shifter conversions for the 6 speeds, so you would have to figure that out. And most I believe only have D and L.

Can't really see a reason to go 6 speed, the 4 speeds work great, especially with big TQ numbers.

Yeah, Allison 1000s are 330lbs dry.

.

[Sirrotica]

Although the 1000 Allison can use a standalone ECM, they work much better with a electronically controlled engine ECM. I see no mention of making one manually controlled on the net. I would consider swapping an Allison into a car probably highly impractical.

The applications for using one with a standalone ECM are diesel truck drag racing, and sled pulling. Without communication with an engine ECM the transmission longevity is compromised because the engine gets defueled during shifts to prolong clutch life. So trying to use one in a street application is going to remove the durability factor anyway.

If you would swap an 8.1 engine and transmission with all the attendant electronics it could happen. Mating it to a non electronic Stratostreak V8 would be a nightmare, IMO.

[rascal455ho]

You should look at the Allison 545 . I used to build Allison transmissions

[ponjohn]

How much power to spin an Alison?

Need to look at the gear ratios, might be stupid separation for towing etc.

[Scott Stoneburg]

Why not just add a gear vendors to your existing transmission?

[dmac]

Originally Posted by Scott Stoneburg

Why not just add a gear vendors to your existing transmission?

Since I'm putting in a new transmission anyway, just figured I'd ask. Gear vendors is definitely an option. But I did love the automatic with the OD. Price-wise, getting a used truck transmission that would last forever sounds good on the surface. But the electronics likely make it an unlikely choice. Glad to get more info from those who replied..

[Scott Stoneburg]

A friend of mine went with a 4L80E, ( 65'GTO with a 505 ) he bought an aftermarket electronic controller and had it wired in. He did finally get it to all work together but it took some time. It developed some issues shifting into 2nd under power. Turned out to be a cracked case. But he also switched to a manual valve body and eliminated the electronic controller. He likes it better this way as the woring and controller were an eye sore to him.

[Sirrotica]

There is currently a thread on PY where forum member Half-Inch Stud, installed a full manual 4L80E in his 68 GTO. Well illustrated from start to finish and he just got it done and is doing road tests with it currently.

http://forums.maxperformanceinc.com/...d.php?t=823023

Or Bauman Electronics/US Shift, has the controller and plug and play wiring harness that is fairly painless to install:

https://www.usshift.com/usq4.shtml

[77 TRASHCAN]

Originally Posted by rascal455ho

You should look at the Allison 545 . I used to build Allison transmissions

I have replaced AT545's, they weigh a lot also!!!! A trans builder we used for a while installed one in a pickup, he said it was NOT a good thing. He could not get it to shift soft enough. AT545 is not an overdrive trans. Has something close to a 3.5:1 low gear, and 4th gear is 1:1