Swap Cabs or Fix Rust

[MSGGrunt]

I recently bought a 2005 Fuso FG140 that has a good amount of rust in each wheel well. And when I say good amount, I mean rotted straight through. I just picked up a very rust free FE120 cab. Looks pretty simple to swap cabs, yes?
The guy who removed the red cab unhooked all the wires going from the cab to the frame, so nothing was cut. I am thinking swapping the whole cab would be easier than cutting out good metal and patching my rust. Thoughts?

Rusted Cab
2005
FG140
Manual Transmission
4M50

Rust Free Cab
2005
FE120
Automatic Transmission
Originally a 4M50 truck


Observations and Questions

• Any issues with the cabs being different where the donor cab is an FE120 replacing my FG140? One being 2-wheel drive and the other 4-wheel drive.
• I already read the only difference between the 140 and 120 is the 120 has a lighter load capacity.
• Will the wiring from the cab to the frame be compatible? The only difference I can see would be any extra wires for the automatic transmission.
• Will my ECU be compatible? Just wondering if there is anything in the FE120's ECU that controls the automatic transmission.
• Manual cable shifter looks easy enough to remove.
• Clutch pedal will need to be swapped over.
• Steering column looks straight forward.
• Assume there are some brake lines with the reservoir being in the dash.

An added bonus on the red one is the interior is in very nice condition. This vehicle was clearly taken care of.

Rusted Cab




Rust Free Cab

 

[SkiFreak]

As I said in your other thread, it should be a much simpler task swapping out the cabs, opposed to repairing the rust in the FG140.
Why wouldn't you just swap all of the electrics from the FG140 into the non rusted cab? Playing "mix and match" between the two is more likely to give you issues.
Given that one is a manual and the other an auto, I fully expect that there will be some minor cab modifications that you will need to make. As soon as you strip everything out, what needs modifying should be fairly obvious.
If the harnesses in the donor cab are in good condition, I'd just keep them as spares.

PS... The red one will probably go faster too.

 

[MSGGrunt]

I was hoping you would chime in SkiFreak.

It would be the small things that I am looking to identify beforehand. For instance, is the vehicles mileage stored in the ECU. With the donor cab being the same year and with the same motor I am wondering if the ECU from the FG will be plug and play?. Is there communication that goes on between the main ECU and the automatic transmission ECU? Do I just leave the transmission ECU unhooked? All things I will discover along the way, but not having to swap out the main cab wiring harness would be nice. Not overly difficult if I do have to.

I am fully prepared that some drilling may need to happen for the clutch and shifter cable but maybe the manual cables share the same opening in the cab as the automatic shift cable?

I have been looking through the factory service manual on how to remove the cab, the clutch, steering column, etc and it seems pretty straight forward.

I don't pick up the cab for a week and then the snow needs to melt so I have a flat and level area to remove the cab. Also, looks like I now have a reason to buy a gantry crane. Any idea on the weight of one of these cabs?

I like the red better than the white, and in this case the saying, "it will just buff right out" is probably true.

 

[glennm01]

How does the frame look?

 

[MSGGrunt]

I was worried about the frame too after discovering the rust on the body but surprisingly the frame looks good. A bit of surface rust with the most being up front, but nothing that can't be fixed with a good wire wheeling and then treated with a rust convertor, I like 3M's Mar-Hyde.

 

[MSGGrunt]

With the dash pulled out of my FG140 I have great access to the wiring harness and found these two plugs that are capped off. Clearly one harness is used in differently configured trucks. I haven't looked, but these could be for the automatic transmission's ECU? Maybe AC related for the trucks that came with AC?

 

[SkiFreak]

I would suggest that you do not make too many assumptions at this point in time.
Wait until you have the new cab, then do a side by side physical comparison to determine what is different and what is the same.

 

[SkiFreak]

I have been looking through the factory service manual on how to remove the cab, the clutch, steering column, etc and it seems pretty straight forward.

The clutch slave cylinder for this engine is inside the bell housing and can only be accessed by removing the gearbox.
Personally, I would be inspecting the slave cylinder very closely when you have everything apart and I would likely put a service kit in it or replace it with a new one.
Maybe that's just me...

 

[MSGGrunt]

Sounds like good preventive maintenance. The previous owner did put a new clutch in the truck, but that doesn't mean he also replaced or rebuilt the slave cylinder. No better time to pull the gear box than when there isn't a bed in the way.

 

[SkiFreak]

No better time to pull the gear box than when there isn't a bed in the way.

Absolutely.