My project is a 1971 chevy longhorn 2wd. The truck is in mint condition minus the tranny and motor. I am looking to put the duramax into this truck and I am starting to get parts for this swap. My question is which transmission will I go with? The Allison has a flashy name that draws a crowd but will the 485 hold up well.Is the Allison worth a little bit more. I dont plan to add any extra power and this truck wont pull anything all that often. I would like to steer away from cutting the trans tunnel up all that bad and I have been told the 485 comes with a stand alone computer? Any help is appreciated

I spoke to a guy at the allison house here in town about the Allison computer and he said if I could snag the computer that ran it and there wouldnt be any problem with it. would a stand alone computer be able to work with the allison or should I cut on the duramax wiring harness? I dont have any freinds at a chevy house to get the good wiring diagrams but I bet I could find a way. The 4L85e that was in some of the early duramaxes do pretty good, I would think that a person should be able to hook one up on a stand alone controller?

If going with a DURAMAX then yes go with an ALLISON. The 4L80/85 can be fully built and hold up in 1st-3rd, but 4th has yet to prove itself to hold up. If going with the ALLISON just make sure your donor has one and your good. My BURB is running an 01 DURAMAX/ALLISON out of a 3500 pickup and works great. I highly reccomend a donor vehicle though as piecing it together will cost a large fortune.

I spoke to a guy at the allison house here in town about the Allison computer and he said if I could snag the computer that ran it and there wouldnt be any problem with it. would a stand alone computer be able to work with the allison or should I cut on the duramax wiring harness? I dont have any freinds at a chevy house to get the good wiring diagrams but I bet I could find a way. The 4L85e that was in some of the early duramaxes do pretty good, I would think that a person should be able to hook one up on a stand alone controller?

No No No No. I allso put a pullout dmax alli where it didnt belong. Its not as hard as you think. GET A Pullout w ally and harness. making an ally stand allone does not allow the TCM to do its job and defuel during shifts.
As far as needing freinds? Ill give you one. HELMSMANUALS.com for roughly 150 bucks you can get EVERY wiring diagram and EVERY bit of info on the donor truck youd ever need. Better than ANYONES info out ther cause its FACTORY info. PPI makes a stand allone harness for the 6.6 Ally combo if you like giving money away then you can do it that way. cutting the trans tunnle isnt gonna be the hard part. Cutting and remaking the engine cross memeber on a 2WD is. Oh and USE the entire rad core suppourt from the donor truck its a really nice fit actually. did I miss anything?:D
Oh yea btw after you get this done and drive it? your gonna burn those trucks in your sig Heh

I need to call around and see if the salvage yards I am dealing with in Idaho have got the whole truck I can snag up and take what I need. I pressumed that the chevy harness would be a pain it the butt once it is out of the donor, but it sounds like that may not be the case.The fabricating for cross members and such dosent worry me Ive got a welding truck sitting in the drive way that dosent do anything anymore. The wiring is what I kinda worry about. Madspeed did you have any trouble with computer feed back from the truck itself like antitheft or cruise control or something like that? That 72 blazer in your sig sounds pretty sweet.I will have to check it out.

The harness for the engine and trans is one piece and has plugs at the underhood fuse panel where everything unhooks. If you don't have EFILIVE or a PPE then you can swap over the BCM and get theftlock to work. I reccomend buying BIGLEYS conversion guide from the page and read over it. It is how he did his swap and will give you a general idea of how to attack yours. Sit down and try to fully plan out your swap in advance to avoid unexpected snags along the way, but also be prepared to improvise when your plans don't work out. Cruise control is simple as well, and the throttle pedal can be sourced out from an 94+ 6.5 truck if you can't fit an 01+ in there. I did my swap as more of a stand-alone swap as I only transferred what was needed to make it all work. I re-used my 95 cluster and only transferred the engine, trans, transfer case(the 261 was bigger than my 241), ECM, TCM, BCM, and the logic module out of the old cluster for a tow/haul indicator. You can run an 01-02 TCM OS and get overdrive lockout and tow/haul to work with the BCM in there. The BCM will function so long as it has the 2 grounds, battery feed and the 2 ignition feeds along with the 2 data bus wires(one for the main communications, and the other is for the theft system). A simple resistor installed across 2 of the key switch sensors and a theft learn will allow it to run with any column, or you can completely bypass it with EFILIVE or a PPE programmer.

There are many many options to make this all work, it all boils down to how much you want to transfer in the end.

Thanks for the heads up on the bigleys guide Ill run a search for that. What year would be the best for a swap? Ideally I wouldnt want to change all that much on the truck, as far as guages would I be able to keep my dash in the truck?

I know that electronically the 01-2's are by far the simplest of all of the DURAMAX's. And yes you can keep your stock cluster, I did in my BURB for the sleeper appeal. If it wasn't for the DURAMAX ALLISON badges on the doors nobody would know what was lurking in my BURB until the black cloud flies and she's off. Also the LB7's are slightly shorter than the LLY's due to the difference in the intake and turbo arrangement change for the variable turbo on the LLY.

Hey fermanator I did a search for bigley I didnt find his conversion guide but found some real interesting reading. This is the same bigley that put the duramax in the red short bed right? What does he go by on here I would very much like to talk with him, Thanks

Hey fermanator I did a search for bigley I didnt find his conversion guide but found some real interesting reading. This is the same bigley that put the duramax in the red short bed right? What does he go by on here I would very much like to talk with him, Thanks


He is not on here, nor will he ever be. We are not even allowed to post his site here because of a dispute between him and starter of DP way back before my time here. And yes he is the one that built up the red short bed 80's CHEVY with a DURAMAX. His website has a conversion section in it with ALOT of good DURAMAX swap info in it.

How about the zf6 transmission that some of these trucks have? I know they are rare, in 2003 I tried to order a brand new chevy with a stick and manual transfer case and the dealer said it couldnt be done. I have never driven one, I have driven alot of miles on my nv5600 and it can be a pain in the but sometimes. It has held up really well. I looked at some of them on ebay and the zf is a little cheaper than the 5600. What kind of flywheels do they use?

The dealer lied cause they were avaliable till Dec of 06. I have two and love them. You need an aftermarket flywheel and clutch but that is the best option if you're used to running nv5600's. Realy good trannys. I've had to do some work to one of mine but I abuse the hell out of it :rolleyes:.

How about the zf6 transmission that some of these trucks have? I know they are rare, in 2003 I tried to order a brand new chevy with a stick and manual transfer case and the dealer said it couldnt be done. I have never driven one, I have driven alot of miles on my nv5600 and it can be a pain in the but sometimes. It has held up really well. I looked at some of them on ebay and the zf is a little cheaper than the 5600. What kind of flywheels do they use?

01duramax6spd, I wish I had looked around more to find the set up I wanted, How about that 4500 in your swap? Do you like the way it went in there? I have had 2 trucks with 4500's and had really good luck with them and they are a little easier to drive I think. On your zf what did you have done to the one I am not real familiar with them I dont think. I had a 2001 ford that had a six speed in it, I have heard they are the same.

I don't know yet cause it's not together yet. We just pulled a Cummins out of the '67. The nv4500's are good trannys. I used to have a BBC truck with a nv4500 and it was great. I just like having 6th. The ZF6 will hold up to 900-1000hp for a while in stock form. I have managed to brake 6th gear but I think that was from towing for a 100K at way too high of a power level :rolleyes: :D. Both ZF trans.

01duramax6spd, I wish I had looked around more to find the set up I wanted, How about that 4500 in your swap? Do you like the way it went in there? I have had 2 trucks with 4500's and had really good luck with them and they are a little easier to drive I think. On your zf what did you have done to the one I am not real familiar with them I dont think. I had a 2001 ford that had a six speed in it, I have heard they are the same.