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Flat fender tub on CJ frame

I just picked up a 75 CJ5 frame, axles and steering, no engine, or trans. going to swap in a Buick 225, SM420 and a dana 20 or 300. most likely the 20 as I already have it.
I would like some of the do's and dont's if you do not mind.
Thank you.
 
You probably already know this but, the '75 frame will yield a slightly longer wheelbase than an early frame. It may throw the "look" off a bit more, in that the front axle will be even more forward of where it would be with an early frame. If you align the rear wheels with the rear wheel well opening, when using an early frame, the front axle ends up about an inch or 1 1/2" forward vs. the original flattie frame. Using the same process, with an intermediate frame, the front axle would be several inches forward. The wheel bases escape me at the moment but, I think you'll be maybe 4" forward. May look funny in the front fender area, if it matters to you.
 
'72-'75 CJ-5 wheel base is either 84" or 84 1/2". Early CJ-5 is 81". Flatfender I want to say is 80". The rear of the frame and rear springs will hang past the rear of the tub and front axle will be pushed way forward. It's do-able but be aware of this. The wheelbase differences are why most people use early CJ frames or DJ frames.


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The 72-on wheelbase is 3" longer (84" v. 81"), but the front clip is 5" longer. So, to have the grille up by the front cross-member where it would be in the CJ-5, you'd have to lengthen the flatty front clip by 5".
 
Forgot about the length in the front as well. Probably go back to using the 56 DJ I have and swapping in the 75 stuff.
Maybe by the time I get to this project I might run across an early CJ5 set up with the 225 already in - for cheap.

Dsylexia is great, you get to relearn stuff you already know!

Anyone ever cut the center out of the 5 frame to shorten it to 80" at a quick glance it looks like it might be doable.


Thanks
 
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The way I do the Flatty on an early 5 frame, you really have to know what to look for to see it. I have the '49 on the '62 frame and drive train now and driving it in the yard.
 
For those of you who have done this, do you normally title the vehicle with the CJ2A title/VIN or the CJ5? I've been mulling over a project like this lately...

-WRM
 
Can I cut the 75 frame and shorten it in the middle to get the 80"
I still have tht 56 DJ frame and maybe a line on a late 60's frame with orig. V6 mounts.

friend says, throw it on the 75 frame, weld a bumper on the rear, throw the body on, weld in the 225 engine mounts, put a winch and a stinger on the front and wheel the hell out of her. enjoy the extra length when it gets tough.
 
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82cj7401 said:
Can I cut the 75 frame and shorten it in the middle to get the 80"
I still have tht 56 DJ frame and maybe a line on a late 60's frame with orig. V6 mounts.

friend says, throw it on the 75 frame, weld a bumper on the rear, throw the body on, weld in the 225 engine mounts, put a winch and a stinger on the front and wheel the hell out of her. enjoy the extra length when it gets tough.
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To me, the appeal of the 55-71 CJ-5 frame under the flatty body is that it looks like a flatty. Per the CJ-3B board article, you can either shorten the rear frame horns, or let the extra length stick out at the back and hide it with a bumper. If you use the '75 frame and flatty body unchanged, it will obviously be a hack job. If that's ok with you, then go to it. But a good flatty body seems like something I would not want to waste on an abomination. JMO.

If you want to cut the frame, I suspect the right place to cut is ahead of the cowl, in the same region where the extra body length is. Could be complicated ... the front of the frame is boxed on these Jeeps, and you'd have to change the spring mount locations. This will likely change the spring/axle geometry - I think the frame has some rise/drop in this area.

What's wrong with the DJ frame? If you can cut the '75 frame, you can build the DJ frame into anything you want.
 
WRMorrison said:
For those of you who have done this, do you normally title the vehicle with the CJ2A title/VIN or the CJ5? I've been mulling over a project like this lately...

-WRM
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I have always titled mine with the flatty VIN. All of the 5 stuff I have used have been from parted vehicles.
 
WRMorrison said:
For those of you who have done this, do you normally title the vehicle with the CJ2A title/VIN or the CJ5? I've been mulling over a project like this lately...

-WRM
Click to expand...

Check your local laws. Some states are very specific that the VIN tag and title go with the frame....
 
Any difference between the 2A frame and a DJ frame? My DJ frame is fine except I would need to weld in saggy steering and v6 mounts. I have a chance at a early v6 cj5 frame for $100. seems that might be the easiest.
 
82cj7401 said:
Any difference between the 2A frame and a DJ frame? My DJ frame is fine except I would need to weld in saggy steering and v6 mounts. I have a chance at a early v6 cj5 frame for $100. seems that might be the easiest.
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What year DJ frame? my 76 postal Jeep the frame was close to an early 5 frame, you could put and early tub on my postal frame.
 
Warloch said:
If you decide to go down this path and need some additional info, let me know. I am finishing my 3rd Flattie body on a 5 frame and running gear right now. I can point you at some do's and don'ts that while may look like they take longer, sure save some work down the line.

I build new mounts on the frame to attach the Flattie body. It allows me to center things better and even out the differences. Now most of my work in with the V6 setup, so take it as you will.
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Additional info on this would be very helpful on my current build. Sorry to dig up an old thread but will also send a private message.
 
Hi Frank -

You can reach the 3B page about the 3B body on an early CJ-5 frame through the Wayback machine:
https://web.archive.org/web/20220129071137/https://cj3b.info/Tech/FrameCJ5.html

What specifically do you need help with?
Suggest you ask technical questions in the forum where we can all participate and benefit from the discussion.
If Chuck put the changes he alluded to on his web site, you could look there.
Chuck has a link to a web site in his profile, but it's a dead link currently.
You can look at the older versions via the Wayback https://web.archive.org/web/20140105004206/http://www.warloch.com/
 
Thanks for the links! I mostly sent a message as I wasn't sure if my post would be seen given the age of the thread. Agreed on sharing of knowledge with the wider group!

I guess I would be most interested in hearing about the best way to go about positioning of a MB/CJ2 body on a CJ5 frame that has factory Dauntless V6 motor mounts. It sounded like the best route to go would be to cut off the old body mounts and weld on new one's but not sure.

I'm assuming I'll have to weld on new grille support brackets: https://www.kaiserwillys.com/products/grille-to-frame-support-bracket-fits-41-49-mb-gpw-2a/

Just trying to get an idea on where to start, like is there one location/dimension that should be used as a datum and work from there.
 
There is this guy on the 2a page that built an mb on a cj5 frame he calls it "bam bam".
I'ld start reading that now. It'll take a day or two to read.
 
FKreider said:
Thanks for the links! I mostly sent a message ...
Click to expand...
NP.
You can look at Warloch's profile to see that he was last here about 2 weeks ago.
Make take a while before he replies.
 
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