XM-778 2 1/2 ton Cargo Truck, W/W

[AndrewH]

Xm778-2

This project continues to move along at the blistering speed of a glacier. I have found another XM778. The Vin on the tag is one digit off from the first truck. Factory sisters! Ill be getting more pictures uploaded so here are a few to tide you over in the meantime. This one runs, drives, stops. It might be in a little better shape overall.
.

 

[frank8003]

"Vin on the tag is one digit off from the first truck"

WOW factor doubled down!

 

[cattlerepairman]

The rims and tires look like they mean business! Nice!

 

[Monkeyboyarmy]

I was hoping that someone on here got it. Had a truck sold but wasn't fast enough or you would have had another bidder. Nice score. Neat trucks.

 

[73m819]

With those big tires, the rear axles have to be spread, wonder how they did it and did the spread go to the rear, if so how long did it make the truck, ?????

 

[gimpyrobb]

With those big tires, the rear axles have to be spread, wonder how they did it and did the spread go to the rear, if so how long did it make the truck, ?????

You saw post #35 right? NOT the actual 1600r20 your thinking of.

 

[waayfast]

October 31st, 2015.

A truely impressive vehicle in many of it's design aspects! Congratulations to the OP for saving it. Probably the only thing rarer in a deuce would be one of the ConDeco diesel electrics with motors in the wheel hubs. The ConDeco units might have solved a lot of problems we have with the seals and bearings on the deuce axle ends, and they probably would have been adaptable to duel power (hybrid electric truck).

Kinda like this?

 

[waayfast]

Compared notes with Andrew and the tires are indeed the same as on the m656 series (xm757).
While on the subject of rare vehicles, the tires were also tested on the Lockheed Twister:
View attachment 588217View attachment 588218

Found another pic--

 

[porkysplace]

I was hoping that someone on here got it. Had a truck sold but wasn't fast enough or you would have had another bidder. Nice score. Neat trucks.

I was watching that one too. I got property about 25 miles from the auction site . It's mostly hills and trees and I'm running out of clear spots to park stuff.

 

[fuzzytoaster]

This project continues to move along at the blistering speed of a glacier. I have found another XM778. The Vin on the tag is one digit off from the first truck. Factory sisters! Ill be getting more pictures uploaded so here are a few to tide you over in the meantime. This one runs, drives, stops. It might be in a little better shape overall.
View attachment 721676.View attachment 721677

I was fighting you for it. I'm glad it's going to a good home.

 

[rustystud]

Did anyone ever find the TM manuals for this truck ? It would be really interesting to look-up the part numbers of things like that brake system for one.

 

[rustystud]

Kinda like this?

What magazine carried this article ?

 

[frank8003]

Must have been a good fire truck, they put almost 75000 miles on it.
Might want to call the fire company that had it and ask the people who worked
on it for the TM's or whatever they have.

https://gsaauctions.gov/gsaauctions/aucdsclnk?sl=51QSCI18414005

 

[waayfast]

What magazine carried this article ?

This is out of the Jan. 1970 Mechanix Illustrated.

We went to a yard sale a few years back and as the lady was closing up she said if I wanted the whole box of Popular Science, Popular Mechanics, Mechanix Illustrated, etc. to just grab them and go----.

Some are in the 30's, several in the 40's, 50's ,60' and few in the 70's. I have a LOT of fun looking thru these. The adds from military surplus companies in these old magazines, just make your mouth water. New in crate Harley 45 flathead engines $97.50. New in crate Allison v-12 Aircraft engines, generators, Jerry cans for 95 cents etc.

Jim

 

[cranetruck]

Did anyone ever find the TM manuals for this truck ? It would be really interesting to look-up the part numbers of things like that brake system for one.

Hey Rusty, the wheels appear to be mounted on standard m656/xm757 axles, which feature 100% air operated brakes (see post #36 in this thread).
Typical illustration of one axle:

 

[rustystud]

Hey Rusty, the wheels appear to be mounted on standard m656/xm757 axles, which feature 100% air operated brakes (see post #36 in this thread).
Typical illustration of one axle:

View attachment 722179

So this truck uses 5 ton axles ? It's not a Deuce ?

 

[cranetruck]

So this truck uses 5 ton axles ? It's not a Deuce ?

Don't know, the part number on the m656/xm757 truck axle (front) is FM210RDAX5, 6.40 ratio...not what is shown here in the first pictures in this thread.

 

[AndrewH]

The tag on the front axle reads FC240RDAX1 6.72 ratio. The axle is dimensionally the same as a deuce.

Rear axle C240RDAX1 6.72 ratio

 

[cranetruck]

Wonder if the grooving wasn't done after the tire was worn to extend the life...
not so easily done on a new tire. Never done it, so I could be wrong, any comments?

 

[AndrewH]

Did some comparing, and playing of course.
The two 778's

778 and M35 just to look at the different clearances and sizes.


778 and M932a2 "New" 16.00x20 and "Old" 16.00x20


and lined them all up just because

As for the center cuts, I think the tires were made that way. The goodyears on the red truck all match and don't have as deep a pattern from the side leaving room for the center rib. They do not look "thin" like some cut tires. At least I think that is what you're talking about.
REO test truck

Yellow 778