Big Diesel swap into a Kodiak
 

No, I'm not a crazy 16 year old kid, I'm a crazy 49 year old shop teacher.

I have a Chevy 5500 with a Cat 3116 and an Allison automatic that is truly gutless. I want to swap in a big rig diesel something on the order of a Detroit Diesel 60 series pre EGR or a Cummins N-14.

Yes I know I'm crazy.

I teach welding and have taught auto shop (and everything else Industrial Tech) and am the local master of "overkill". I got this truck with the intent of building a removable 28' cabover camper but the silly thing is without testicles.

I've decided to forgo the camper and just go with building an unstoppable RV out of it. I have mentored bunches of students through countless engine swaps and it's time for me to go big.

I can fab nearly anything and know this will require an extensive amount of carving, wiring and plumbing.

The frame rails are (from memory) 33" apart. I do not know what the standard big rig frames are set at.

My questions are almost limitless but let's start with these two:

What is the spacing of a big rig's frame rails?

I'm a big fan of manual transmissions - what would be a good start for me to look into for one of the above engines?

Thanks in advance folks!

You would do better putting the Kodiak cab on the class 8 chasis.

NOTHING on the Kodiak would be any good to use on a swap, frame rails, too weak, front end, too weak, not enough room for engine and radiator without extensive firewall reworking.

Rear axle not strong enough, easier and cheaper to mount he Kodiak cab on say a Freitghtliner frame, they are cheap easy to come by and most are Detroit powered.

The frame rails on my KW are 34" wide.......and they are 3/8 thick, I have a 13,200 front axle for the Cat, Detroits are a little lighter, but not much.

Thank you for the reply Maniac. The problem with swapping the chassis is the registration. I had a Freightliner FL70 and DMV would not let me register it as an RV - even after I went through and added the 4 of 7 RV items they told me I needed.

They seem to be OK with the C5500 though. We are on the road now but I had my son measure the frame and it too is 34" wide. I extended the frame when I got it (the guy before me cut it off right behind the rear spring mounts) and if memory is correct I believe it is 5/16" thick so not too far off the 3/8". I'll never be exceeding 26K GVW so I'm not too concerned about twisting the frame. The heaviest load I'm going to tow is a 14K dump trailer that it is already towing around.

When I got the truck it had a single cab and a sleeper on it. We bought a crew cab and sectioned the old firewall and welded it into the crew cab so I've been down the "extensive firewall reworking" road. ;) My big concerns are starting with the correct engine/transmission combination. By putting something so big in the medium duty truck I'll not ever have to worry about overworking the engine. Right now it is taching 2,700 - 2,800 (pretty much balls to the wall) at 65-70 on the freeway. This little cat is not going to last very long at that speed.

As we will eventually build a motor-home on the chassis and would like to drive around the country when we retire (8 years from now) I'd like something that I don't need a CDL to drive and that will cruise up the hills at speed without me worrying about beating the crap out of the drive-train.

So the 34" is a go. Now I need to research the engine/tranny combo. I've read a bunch of posts and most of them are something to the tune of:

This engine is the best - everything else sucks.

I know that any used machinery is going to have problems and as I'm going to have to custom fab just about everything, I'm looking for the best platform to begin with. I don't mind older stuff as it usually has less wiring to contend with. Just as long as parts are easily / cheaply obtainable.

Thanks again!

Mikey

Here is the original truck with the single cab and sleeper - we took it to the dunes and slept in it and swore never to do that again! On the back of the frame is the frame section I bought from American Truck Salvage in Phoenix.

[ATTACH=CONFIG]1350[/ATTACH]

These are shots of tabbing in the frame. Single V welded with 8018.

[ATTACH=CONFIG]1351[/ATTACH]

[ATTACH=CONFIG]1353[/ATTACH]

This is the tail plate I fabbed to accommodate lights and a hitch. The prior guy had lights screwed to a 2 x 4 across the back of the frame. you can just make out the back of the crew cab we swapped.

[ATTACH=CONFIG]1352[/ATTACH]

This is after welding and grinding. teh 4 vertical slots are to acccomodate the "Extendo hitch"

[ATTACH=CONFIG]1354[/ATTACH]

Thanks again for your input!

Mikey

#1 - Here is the original truck with the single cab and sleeper - we took it to the dunes and slept in it and swore never to do that again! On the back of the frame is the frame section I bought from American Truck Salvage in Phoenix.



# 2 & #3 - These are shots of tabbing in the frame. Single V welded with 8018.


#4 & #5 - This is the tail plate I fabbed to accommodate lights and a hitch. The prior guy had lights screwed to a 2 x 4 across the back of the frame

[ATTACH=CONFIG]1364[/ATTACH]
[ATTACH=CONFIG]1363[/ATTACH]

Sorry, I don't seem to be able to upload picts or attachments...

That series 60 physical dimensions, namely weight will destroy your c5500.

Empty, my front axle weighs 11,800. The only thing it really carries is the engine and tranny.

Torque for a factory engine is 1680 lb-ft. HP is 515. I also have the 14L though.

There are class a rv's with this engine. So I don't know what line the state folks are giving you.

Pics won't load,

You will have to replace the front axle and springs for the weight, My Cat powered KW is 11600 on the steering, without a trailer,maybe the steering box also, another thing is cooling, even tho it wont really be working that hard you will need room for a much larger radiator than you have now.

You might end up with very little interior space because of the engine length, and firewall mods.

The Detroit is a great engine for this, and just about any trans will work, a 9 speed overdrive should do just fine.

As far as CDL, in the RV's they don't ever enforce it, seems to be a "gray area"

Interesting build, but I agree with maniac. Just swap the body over onto another complete rolling chassis, what the state DMV doesn't know won't hurt them. Been there done it and still doing it!

i agree with maniac too. i see a lot tractors online that are registered as an RV.