Jeep cj or Hummer. which would be easier to convert

I have a 1977 jeep cj, 258 cubic inch, carbureted or a 2007 Hummer 6 liter fuel injected. I understand I have to deal with the carburetor in the jeep, and it is a small engine. it is a very light vehicle and has very low gearing.
I would have to cut the rear body off the Hummer. that does not bother me. me and one passenger is all I need.
both of these vehicles are used around the farm and travel only 7 miles to town most of the time.
maybe i should just sell both and use the horses.
any comments would be greatly appreciated.


If I owned those two I would choose the Jeep. I’ve never really liked how slow Hummers are to begin with.

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The 258 is the AMC Straight Six right? Great engine if that’s the case.


Hello Mike and welcome to the DOW.

You may get a little info from the below to help make a decision.

Corn and hay may be going up in price soon LOL


I would build a gasifer unit that would fit on the back of the jeep. To make it simpler a charcoal unit vs. A wood gasifer because of the weight factor involved. No one has done a conversion on a Hummer as yet.
Do the easier one first which is in my opinion is the jeep. Then tackle the other once you have learn the other 75 % of gasification that is after you build and learn how to run a gasifer unit on a vehicle. The charcoal units are much easier to build and less monies to build one. Like they say get your feet wet before take the big dive. Order the book Have Wood Will Travel and start reading.


another vote for the jeep, and depending if its a cj5 or cj7. I would say a five would get a charcoal gasifier, smaller space taken up and not as much cooling is needed from the builds I have seen. I think you could build a wood gasifier for a cj7, but would need to be a bumper or receiver mount to get the system low enough to have room for adequate hopper capacity and still have room for some cooling tubes. could integrate the cooling tubes into the roll cage as jan and I talked about before to save space. The straight six makes good bottom end torque and is reasonably low rpm which would act like a truck on woodgas. not a speed demon but doable, and it can be made compact. look at @don_mannes geo tracker build, even smaller and tighter then the jeep


I vote for the Hummer if it is the HummerEV. then you can pull the engine from the jeep and turn it into a generator. :stuck_out_tongue:

With either, you might be able to get a charcoal gasifier in like the steel 5 gallon army gas cans and attach it to the back. along with maybe something covered with one of those spare tire covers.

I vote for the hummer because I haven’t seen anyone else do one. Jeep would be way easier though. Welcome to the site. Do votes count? I have bad memories.


I would not do a hummer. Especially if the point is to save on fuel and be useful. It has no bed so it cant haul anything back there and takes alot more time to convert. Its heavy and sucks down fuel for no reason unless you have a trailer hooked up.

Also unless you can find somethat has converted that same engine and computer system you dont know how it is going to run.

Not trying to be negative a cj would be really cool.