FJ55 body on an FJ80 frame. Am I Crazy!!

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andrew.fletcher

andrew.fletcher

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I'm finally (hopefully) picking up a gutted '76 FJ55 from a friend in Tucson over the Holidays and dragging it back to California. I searched for some old threads on this topic but didn't have much luck so I'm wondering if this is too crazy to try. Like I said, it's basically just a pretty solid shell, 4 worn tires and a steering wheel. The major obstacle I see is length and width. I need to find the specs for both but I did find one thread that said the 80 frame needed to be cut 7" but nothing was said about width. The big questions like where the steering wheel would end up and the tranny are my biggest concerns. If anyone out there has done this or at least tried or know of someone who has, let me know.
Thanks
Drew
 
There are three big issues that I see. I'm sure Andre has run into some others.

Length - You need to cut about 5 inches from the frame. It's gonna be strange because the frame narrows. See Andre's thread for a nice solution. You can also add 5 inches to the body. That's the direction I think I'm headed.

Width - about 4 inches per side. Mine sticks out on my 80 axled wheeler and looks OK, but I don't know how my dd project is going to solve this. I think the windshield is going to be the most costly part of widening, but there are a lot of issues. You'd need two rear doors to make one. Rear window weatherstripping is already really costly, etc.

Motor relation to the axle - this one is big and mostly overlooked. If you plan on keeping the stock drivetrain, you will need to move the axle (upper buckets are not easy to move) the engine, or the cooling system. The 80 engine is about 5 inches forward of the axle compared to a 55.
 
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Thanks guys! This gives me some serious reading to do over the holidays. I thought putting a Chevy engine in my MG was a challenge but it's nothing compared to this. All I had to do was cut out motor mounts and drill a couple of holes into the tranny cross-member. That and some re-wiring and I was done!
If not an 80 series frame, has anyone looked at other options, ie. a Tundra or 4 Runner? Just a thought.
 
I'm looking hard at a Tundra, Sequoia or a 100 series.

I'd like a dd that can tow the War Pig. That means V8 and wheelbase.

There's a wrecked Tundra being auctioned in Appleton with 3700 miles on it, but I'm nowhere near ready for it.

Here are some numbers, best that I can find them. Some don't look right to me

FJ-55 106 inch WB/ 57 inch width/ 55 inch track
FJ-80 112 inch WB/ 65.3 inch width/ 63 inch track
100 112 inch WB/ 69.6 inch width/ 64 inch track
3rd gen 4rnr 105.3 WB/ 66.5 inch width/ 59 inch track
4th gen 4rnr 109.8 WB/ 73.8 inch width/ 62 inch track
Taco 109.4 WB
FJC 105.9 WB/ 63.2 inch track
Tundra 128.3 WB
Tundra 4 door 140 WB
Sequoia 118.1 WB/ 78.9 inch width/ 66 inch track
T100 121.8 WB/ 75.2 width

The Tundra and Sequoia might be tough to do the track without widening the 55 body.

Any option is going to have engine to axle placement issues. The Pig has the axle way forward compared to most new vehicles.
 
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IMO the 80 series frame really isn't too bad to do, just takes a lot of work with that frame shortening, not too much work to add the body mounts. Other than that not too hard IMO. The rear frame movement I did because I trimmed out the rear...
 
The 4runner numbers look a little bit big, that's for sure. I'm visiting relatives and there's a 4th gen next door, I need to break out the tape measure. I didn't think Sequioa's were that big either.
I want to be able to tow also, only about 3500 lbs though (MGB and trailer with gear). I even thought about going the Highlander Hybrid route until I realized they're unibody. A bummer too since it's close on length but still has the track issue. Am I right in thinking track is the width of the tires?
Highlander 106.9 WB 62.0 track
Tacoma is looking pretty close on the numbers but I wonder how close the frame would be. I really don't want to try and widen the Pig, that's beyond my skill set and price range to have someone else do that.

Good research project for the weekend.
 
andrew.fletcher said:
I'm finally (hopefully) picking up a gutted '76 FJ55 from a friend in Tucson over the Holidays and dragging it back to California. I searched for some old threads on this topic but didn't have much luck so I'm wondering if this is too crazy to try. Like I said, it's basically just a pretty solid shell, 4 worn tires and a steering wheel. The major obstacle I see is length and width. I need to find the specs for both but I did find one thread that said the 80 frame needed to be cut 7" but nothing was said about width. The big questions like where the steering wheel would end up and the tranny are my biggest concerns. If anyone out there has done this or at least tried or know of someone who has, let me know.
Thanks
Drew
Click to expand...
So whatever came of your build?
 
I’ll avoid this path. 😏
 
For those who are pulling this up on a search and are unaware of the builds involving 80 series chassis’s since this thread died, here’s a list I’ve compiled -

FJ55 With FJ80 Frame Swap



Builds - “It’s only an axle swap and a motor swap” aka AK2AL aka Dream Build - https://forum.ih8mud.com/threads/its-only-an-axle-swap-and-a-motor-swap-aka-ak2al-aka-dream-build.1191428/page-9





rear body mounts - https://forum.ih8mud.com/threads/rear-body-mounts.596973/page-70





Builds - FJ55V : This little piggy came home. - https://forum.ih8mud.com/threads/fj55v-this-little-piggy-came-home.1091605/page-39





Builds - 79 Aussie BJ55 build - https://forum.ih8mud.com/threads/79-aussie-bj55-build.891702/page-27



Biodiesel Piggie #2 Buildup (was Sad Sad day...) - https://forum.ih8mud.com/threads/biodiesel-piggie-2-buildup-was-sad-sad-day.92355/page-13



Biodiesel Piggie #2 Buildup (was Sad Sad day...) - https://forum.ih8mud.com/threads/biodiesel-piggie-2-buildup-was-sad-sad-day.92355/page-13



The 1974 Surf Wagon... - https://forum.ih8mud.com/threads/the-1974-surf-wagon.601793/page-7
 
Here are also some pics of the frame shortening procedures done in a couple of the above mentioned threads

IMG_2431.webp


IMG_2429.webp


IMG_2430.webp


IMG_2428.webp


IMG_2427.webp


IMG_2426.webp


IMG_2425.webp


IMG_2424.webp
 
RUSH55 said:
For those who are pulling this up on a search and are unaware of the builds involving 80 series chassis’s since this thread died, here’s a list I’ve compiled -

FJ55 With FJ80 Frame Swap



Builds - “It’s only an axle swap and a motor swap” aka AK2AL aka Dream Build - https://forum.ih8mud.com/threads/its-only-an-axle-swap-and-a-motor-swap-aka-ak2al-aka-dream-build.1191428/page-9





rear body mounts - https://forum.ih8mud.com/threads/rear-body-mounts.596973/page-70





Builds - FJ55V : This little piggy came home. - https://forum.ih8mud.com/threads/fj55v-this-little-piggy-came-home.1091605/page-39





Builds - 79 Aussie BJ55 build - https://forum.ih8mud.com/threads/79-aussie-bj55-build.891702/page-27



Biodiesel Piggie #2 Buildup (was Sad Sad day...) - https://forum.ih8mud.com/threads/biodiesel-piggie-2-buildup-was-sad-sad-day.92355/page-13



Biodiesel Piggie #2 Buildup (was Sad Sad day...) - https://forum.ih8mud.com/threads/biodiesel-piggie-2-buildup-was-sad-sad-day.92355/page-13



The 1974 Surf Wagon... - https://forum.ih8mud.com/threads/the-1974-surf-wagon.601793/page-7
Click to expand...
Nice work Rush!
 
RUSH55 said:
By far the most popular method is to remove the link bar mount on the outside and cut the frame at the factory joint. There are other ways to do it, as some have shown, but there seem to be a few benefits doing it at the factory joint.
Click to expand...


I have done about ten now. All but one have been extensions though. Doing one right now actually, my 80 Ute, which is an extension too. I always cut off the rear lower control arm mounts and cut the frame there because the frame is straight there. Only the first one did I plate the outside of the frame rails.

D80BFC79-9F09-4EC2-BEE3-132084D08390.jpeg
5485E3C9-99AB-4EA2-AD36-B58B8B292D20.jpeg
57774640-AD43-4FC9-8EA0-D9CE122F994A.jpeg


Cheers
 
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