Allison Gearbox?
 

Anybody mate a 5/6 speed Allison to GM6.2??

I'm running a 4l80(no E, its a manual box) in my racer now. I dont need HUGE amounts of more power, I need more power to the ground. Hence, looking for more gears.

Is there an adapter?? Thoughts??

Thanks!

yes they do find you self a 6.2 mail truck or step van or there one motor and tranny for sale on ebay item number 110494869271 you only need the adapter all allison tranny are the same i have a 545 4 speed and this winter i'm switching it out for the 1000 5 speed if you go with the 5 speed your going to need a stand alone ecu for that google stand alone allison 1000 and you will find some companys that sell them dont know if they have the stand alone for the 6 speed yet.

you can do it but its going to be expensive. almost more cost effective just to get a gears vender overdrive. i hear there durable too.

You da man! Thanks, I had no idea...

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I'm a huge fan of GearVendor's stuff. Unfortunately, they don't work with full time 4wd's like mine because the bolt on after the transfer case, not between.:dang:

You are right though, that 5/6 speed Allison box is danged 'spensive!!

yeah i always thought it would be cool to have a allison 1000 behind a 6.2/6.5 but i dont have the cash. let us know how it goes on the conversion. what transfer case you using. bet your going to need to get a new one or at least some adapter plates.

are you running a civilian or military truck???

If I was you (being a HMMWV mechanic) I would suggest using the factory t-case that is hooked to the allison if it comes from a chevy truck...do plan on shortening your already short rear driveshaft...your best bet would be to PPE and talk to them about the duramax/ally swap they did into their HMMWV...

My truck is a '92. Very first civilian year, number198 off the line. That means it is, more or less, a HMMWV with 12 volt electrics. Most of the parts are the same. I ditched the TH400 for a custom manual bodied 4L80 just to get the extra gear. I was just looking to see if doing an Allison gearbox would get me TWO more gears with the same power. Might even be able to do the A-son gearbox and do the Dmax later. Gonna have to wait though; next big money spent will probably be on a complete coil over suspension with triple bypass seconday shocks an full bumpstops.

Oh man, I've seen that PPE truck. I would give ALOT to have mine done up the same. Unfortunately, it would cost about as much as my whole H1 cost me. Serious cash, but serious fast!

Might just have to do that someday.:tu:

hi just so you know the allison tranny is a lot larger then the 4l80 and heavier your going to have to in large the tranny tunnel and make some way to mount it have you looked into the new 6L90 theres one on ebay item # 290349904482for $1500.00 for 4X4 check it out might be the way to go.

Tranny tunnel on a H1 is about 3 foot wide! Plenty of room in there. Thanks for the idea and link. The 6L90 had not even hit my radar. I searched around but I dont see any way to get it to shift though as it its an electronic box. Did not see any aftermarket ECM for it. Will keep an eye on this box though.

Cheers!

did a google on the swapsome have all ready done the 4L80 to a 6L80 swap so you could do it you would need a stand alone ecm on this web site theytalk about it PerformanceTrucks.net Forums - Powered by vBulletin maybeyou can get some info off it the 6L80 is just a 4L80 with some mods done to ive seen some company in my street rod mags selling them with a emc for them

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ok there a company that make a manual valve body 6l80.com

Man, Why waste an allison on a 6.2? If you're ready to upgrade to 21st century technology I'd probably be more inclined to swap the duramax and allison in one go... Sorry but I just think that 6.2 won't do the allison justice.

Oh, I'm with you on this one brother. I would LOVE to put in the whole Dmax/allison gearbox combo. I was looking to do it in stages though, spreading the load on the wallet over time. Its about 30 grand to do a full Dmax/Allison swap on a H1 these days. Even if you do it yourself your looking at 20K+.:argh:

My thinking was to start with the A- gearbox. That would give me at least 1 extra gear, hopefully two. It would be amazing to be loping down the motorway at 80 and only pushing 1500 revs. Or, blasting across desert lakebed at 120+. Later, install a Dmax.

Big wrinkle in the works is if I ever go whole hog with the Dmax, then body will come off again. I mean, really off. For the class of racing I do, I dont need a real body. I would only iinstall the firewall, the hood and the outer panels. I would remove the entire rest of the body and mount the remaining bits to the roll cage. Save at least a tonne on weight. Not really ready to do that yet.

keep us updated:tu: