FJ40 Frame Swap Questions - 79 frame, 77 tub, 69 body mounts (1 Viewer)

[geohaskett]

I recently came across a nice 1979 FJ40 frame. The VIN stated it was made in 5/1979, however the vehicle was registered as an 1980 rig.

My current 1977 FJ40 has a lot of rust in the frame and some ugly welds, etc.

I want to swap out the frames and wanted to make sure that this could be done by simply replacing the body mounts on the 1979 with mounts from an earlier rig.

I have a donor 1969 frame. Can I use the body mounts on the donor 69 to replace the body mounts on the 79, so that my 77 body can bolt on to the newer frame?

Thanks,

 

[shawnfj40]

No the 79 frame is not a direct swap to the 77 body. You will be far ahead to just find a 78 and down frame or a 79 up tub. I am pretty sure your 69 body mounts are fine for the 77 tub.

 

[geohaskett]

So there are differences in the main frame alignment other than the body mounts?
This frame is super clean and appears to have been restored at one point.
I was hoping that removing the 79 body mounts and installing the 69 mounts would be a possible solution.
Finding a really clean frame is getting harder now days.

 

[shawnfj40]

Yes there are differences however people put 40 tubs on 80 frames so I am sure it can be done. It all comes down to how much work you want to do to make it happen.

 

[geohaskett]

If the main channels have the same angles and the only differences are the mounts, then I am hoping to swap things over.
I already bought the frame, primarily for the axles, so I the frame is already purchased and super clean.

Are you saying that the main side frames are angled different?

Thanks again for you assistance on the topic.

 

[Mace]

The differences are the mounts (but not all of them) and not the actual frame dimensions. You can take the Frame mounts off the 68 for most of the mounts. The main issue is the rear xmember/bumper. On the 68 it uses round taillights. On your 77 the taillights are the ~8" long rectangular style. The 79 has the same taillights, however the rear body mounts on the 79 are completely different than the 77. If you can reuse the rear cross member from the 77 and the other body mounts off the 68 you can make it work.

Not easy, but not terribly hard either.

I have a 74 tub on a 79 frame.

 

[geohaskett]

Okay, so I'm looking at replacing the rear crossmember and the body mounts.
IF that is the case, then I'd like to go that route as the frame is the cleanest frame I have seen in a long time and I already paid for it when I bought the axles, etc.
Having someone swap out the mounts here in Idaho shouldn't be too expensive.
Thanks.

 

[bikersmurf]

I'd go for it. Worst case you'll need to track down a new reproduction rear crossmember. I'm sure the 80 one could be modified though. The swap isn't to bad once prepped. It could be done in a weekend... or 3. I did a frame swap years ago solo (with big cherry pickers help).