M1079 van body on M1078

[SteelPeak]

I have a m1078 and am brainstorming ideas for a basic box on the back. I like that the m1079 van bodies are stout, well insulated and (in theory) would be a fairly simple swap with the flatbed. Is there anyone out there who can take a quick look at their 1079 subframe and give me an idea as to how hard it would be to remove... specifically the front/cab end (pics would be awesome!). My main question is, would it be easier to make the swap from the subframe up or to keep subframes in place on both trucks and just transfer the box??? Option two would require me to modify my 1078 subframe with the springs taken from the 1079 for a stock like mount. Without having a 1079 to look at I was assuming it would be straightforward, but I could be wrong. Any insight would be a huge help. Thanks guys!

PS- selling my truck and buying a 1079 is also an option, however, I've bonded with my truck and would rather not start over with something new. Plus it's an A1 (love) and I just haven't seen very many A1 m1079's around.

 

[porkysplace]

I don't have them downloaded , but most of what your looking for can probably be found in the TM's . In the body section.
TM-9-2320-365-20-4
Somewhere around page 136 (from a google search).

 

[Oxyacetylene]

It's funny you should ask. I am actually sort of working on this, and I am part of the way there. My truck is not an A1, but it is a winch truck. I think that would make a nice combination! I have the van enclosure, frame rail, and wiring. There are more differences than there seems at first glance. The conversion will be a lot of work and I just haven't had the time or motivation to get it done. Here's what I can tell you:
- The top frame rail section extends into the area where the spare tire and air cleaner cross member go. It tapers on that end though.
- M1079 section of frame has a different attachment for the slide out lift bars, and the bars themselves are different.
- M1079 uses a different mud flap holder.
- M1079 has an extra plate sandwiched between the light brackets and the frame rail, which connects the upper and lower sections together. The M1078 does not have this.
- M1079 has wiring to run the marker lights, air circulation fan, and emergency lights inside the enclosure. This connects at the front of the box.
- M1079 van enclosure mounts to the frame rail with 4 bolts, including two springs. The mount pads where it mates up are welded to that upper frame rail. The design lets it move a little.

Because of the frame differences I would like to just swap everything to make it like OEM. Cutting the huck bolts inside that crossmember mentioned above is kind of tricky as well as the ones behind the toolbox. At least the toolbox can be somewhat easily removed. This makes for about 40 of those huck bolts to cut off the M1079 and a few less on the M1078. Getting the frame and other parts off the M1079 was the easy part for me since it was a parts truck that was being broken down.

I'm sure it will be worth it if I ever get it done

 

[coachgeo]

It's funny you should ask. I am actually sort of working on this, and I am part of the way there. My truck is not an A1, but it is a winch truck. I think that would make a nice combination! I have the van enclosure, frame rail, and wiring. There are more differences than there seems at first glance. The conversion will be a lot of work and I just haven't had the time or motivation to get it done. Here's what I can tell you:
- The top frame rail section extends into the area where the spare tire and air cleaner cross member go. It tapers on that end though.
- M1079 section of frame has a different attachment for the slide out lift bars, and the bars themselves are different.
- M1079 uses a different mud flap holder.
- M1079 has an extra plate sandwiched between the light brackets and the frame rail, which connects the upper and lower sections together. The M1078 does not have this.
- M1079 has wiring to run the marker lights, air circulation fan, and emergency lights inside the enclosure. This connects at the front of the box.
- M1079 van enclosure mounts to the frame rail with 4 bolts, including two springs. The mount pads where it mates up are welded to that upper frame rail. The design lets it move a little.

Because of the frame differences I would like to just swap everything to make it like OEM. Cutting the huck bolts inside that crossmember mentioned above is kind of tricky as well as the ones behind the toolbox. At least the toolbox can be somewhat easily removed. This makes for about 40 of those huck bolts to cut off the M1079 and a few less on the M1078. Getting the frame and other parts off the M1079 was the easy part for me since it was a parts truck that was being broken down.

I'm sure it will be worth it if I ever get it done

Would you be kind enough to photograph the bolded items in your list I quoted above. Am doing a similar project but using different body than the van enclosure. Much thanks in advance

 

[Oxyacetylene]

Would you be kind enough to photograph the bolded items in your list I quoted above. Am doing a similar project but using different body than the van enclosure. Much thanks in advance

Yeah I'll try to get some pictures, but it might be a while. The components are already off the M1079 so I can't show how they are installed yet.

 

[FMTV Truck Sales]

Keep in mind that the M1079 leaf springs are rated at 14,946 lbs.

M1078 is only rated at 8,722 lbs.

BIG difference!

 

[Oxyacetylene]

Keep in mind that the M1079 leaf springs are rated at 14,946 lbs.

M1078 is only rated at 8,722 lbs.

BIG difference!

Is there a different NSN for the two truck springs? To my poorly calibrated eyeballs they look the same on both trucks. That difference seems like it would be the difference between a 2.5 ton and 5 ton rear.

 

[FMTV Truck Sales]

Yes - all info is in TM's

 

[SteelPeak]

Thanks for replying and all the info guys! Oxyacetylene, in your opinion, would it be easier to mount the van body on the original 1078 subframe...taking the with springs, etc from the 1079? Or would swapping subframes be the way to go? Thanks for the info on the leaf springs fmtv...very good to know!

 

[Oxyacetylene]

Yes - all info is in TM's

In the one TM, 9-2320-365-34-2, in Appendix F, there is a singular NSN for a flat spring (5360-01-360-2023). What is the NSN for the heavier spring?

 

[FMTV Truck Sales]

In the one TM, 9-2320-365-34-2, in Appendix F, there is a singular NSN for a flat spring (5360-01-360-2023). What is the NSN for the heavier spring?

See -24P

 

[Oxyacetylene]

See -24P

That one lists two part numbers:
- 12422509 UOC: LAD, LWD
- 12422510 UOC: LAA, LAB, LAC, LWB, LWC

Edit: found the above codes in the -10 manual. The LAD and LWD are M1079 and M1079 w/winch.
2nd Edit: I would be curious what the difference between them is. I wonder if the heavier rating one has an extra leaf or two. *sigh* I guess I need to look for those now...

 

[FMTV Truck Sales]

Both spring packs have four springs...12422510 springs are 18mm and 12422509 are 21mm.

 

[coachgeo]

With cost of NOS and Previously Used by some vendors..... Im guessing you could have custom springs made to order for less cost, but that is only a guess. Having fresh springs for such a project might be wise anyway if one plans to go camper route with the box and outfit it with grey, black, and water storage tanks... cabinets etc.

 

[Oxyacetylene]

Both spring packs have four springs...12422510 springs are 18mm and 12422509 are 21mm.

OK that explains why I couldn't tell a difference. Happen to know a good source for a pair? If I pull the bed, then I think the difference with the box wouldn't be that much. As long as I don't load the box up with heavy stuff then maybe it would still be OK.

 

[wheelspinner]

Happen to know a good source for a pair?

Are they still on the truck the box came from?

 

[g4g63tgvr4]

I put an m1079 box on my m1078 chassis with custom captured spring mounts I made. I was also able to remove over 1000lbs in useless items from the box.

 

[coachgeo]

I put an m1079 box on my m1078 chassis with custom captured spring mounts I made. I was also able to remove over 1000lbs in useless items from the box.

Am interested in your captured spring setup. Can you offer up some pics? Resources? How you determined what spec. springs to use etc?

 

[g4g63tgvr4]

https://www.steelsoldiers.com/showthread.php?165285-First-LMTV/page3

 

[Oxyacetylene]

Are they still on the truck the box came from?

No, I wish they were. I could have gotten them actually before that section was scrapped, but like I said I never imagined they were different. I didn't spot the 2mm difference LOL. Kicking myself now, but hey, it happens. I can probably save enough weight that it won't matter, but I would like to at least be able to install them if needed.

https://www.steelsoldiers.com/showthread.php?165285-First-LMTV/page3

Can you give us a quick rundown of the items you removed to save weight? It looks like you eliminated the side spreader bars and the channel that held them? I was thinking I would at least take up those metal strips that are bolted in the floor. That would probably save a couple hundred pounds.