5 Ton

Please help us build up our 5 ton article!

Here's a start:

[h=2]Identification[/h]
There were 3 main series of 5 ton trucks used by the United States Military.
Here they are broken down by identifying characteristics and production years.

M39/G744 Series (1951-?)

• Air filter mounted externally on pass. side fender (Mack & Multifuel) or under hood (gas engine only)
• Flat grille
• Continental Gas Engine, Mack Diesel, or LDS-465 Multifuel

M809/G908 Series (1971-1983)

• Air filter mounted externally on driver's side fender
• Center of grille extended forward (similar to Deuce)
• Some have grille of steel tube
• All have Cummins NHC-250 Naturally aspirated 6cyl. Diesel

M939 Series (1983-?)

• Wider hood, flat and different styled grille
• No external air filter
• Allison automatic transmission
• Air brakes
• M939 and A1 series powered by same NHC 250 as the 809 series
• M939A2 powered by Cummins 6CTA 8.3 Litre diesel

[h=2]M39/G744 Series[/h]
Engines
Continental R6602 Gasoline Engine- M39 series
Mack ENDT-673 Diesel- M39A1
LDS-465-1A Turbocharged Mutifuel Engine- M39A2

Transmissions
M39 and A2 series with Gasoline engine or Multifuel engines- Spicer 6352 5 speed/manual (direct drive parent of the 3053A in the 2 1/2 ton trucks)
M39A1 with Mack - Spicer 6453 5 speed/manual (OD)

Most Common Variants
M51- Truck, Dump
M52- Truck, Tractor
M54- Truck, Cargo
M139- Truck, Bridge/Chassis
M543- Truck, Wrecker, Medium

Other Variants
M246- Truck, Tractor, Wrecker
M41- Truck, Cargo, with 14.00 "Super Single" tires


[h=2]M809/G908 Series[/h]
Engine
All M809 series trucks were powered by the naturally aspirated 6 cylinder Cummins NHC-250

Transmission
The Cummins was mated to the Spicer 6453 5 speed manual (OD).
As per the Spicer catalog, final drive ratio for the overdrive 6453 transmission is .78.
Variants of that transmission:
6453A .83 Overdrive
6453


Most Common Variants
M811- Truck, SEORLT, Gull Wing (Mobile Machine Shop)
M812- Truck, Rocket Launcher (?)
M813- Truck, Cargo, LWB (Long Wheelbase)
M814- Truck, Cargo XLWB
M815- Truck, Bolster
M816- Truck, Wrecker
M817- Truck, Dump
M818- Truck, Tractor SWB
M819- Truck, Tractor, 6x6 Wrecker
M821- Truck, Bridge Transporter (LWB)
"X" Prefix denotes pre-production run, as in XM813A1

Marine Corps Modifications/Variations
Marine trucks were outfitted with Detroit locking rear differentials. (To aid operation in sandy conditions, i.e. beach landings) Their air filters were equipped with extended breather stacks, and they were equipped with fording kits.
Some Marine M813s were outfitted with ISO beds, with stowable sides and accomodations to stow troop seats and canvas bows. They were designed to carry standard ISO containers.

[h=2]M939 Series[/h]
Engine
Cummins NHC-250 Diesel- M939 and M939A1 series
Cummins 6CTA 8.3 Litre Turbocharged Diesel- M939A2 series trucks
-Interesting note- the 6CTA8.3 is smaller than the NHC250, rated at a slightly lower HP. It is identifiable by A) its single-cast head, B) it's turbocharger, and C) its smaller size

Transmission
All M939 series trucks were equipped with an Allison automatic transmission

Transfer Case
High Range: .732, Rated Input Torque- 7350 Foot Pounds
Low Range: 1.79, Rated input Torque- 650 Foot Pounds
Oil Capacity: 13.5 Pints
Weight: 460 Pounds

Most Common Variants
M923- Truck, Cargo
M925- Truck, Cargo, with winch (hydraulically powered)
M931- Truck, Tractor
M936- Truck, Wrecker
M945- Truck, Chassis (Bridge Truck)

Some Marine M923s were outfitted with ISO beds same as their M813 trucks

Production Note: The M939 series was originally designed as an upgrade package for the M809 series trucks. They only began to be produced from "scratch" when the M939A2 series began to be manufactured

The M939 series and the M809 series trucks are being replaced by the FMTV (Family of Medium Tactical Vehicles) in the Army, and the Oshkosh MTVR/MTVR-II series (Medium Tactical Vehicle Replacement) in the Navy and Marine Corps.

Great Idea having this sections for the 5tons! When will you start the 5ton "Hot Rodding" section?

We have a M543A2, were dose this fit in?

I just discovered this thread, so if all the inhabitants are deceased or
still in prison or a rest home, I am not worried until I follow those
(previous) inhabitants.

anywhom,
I hate to sound as though I know what I am talking about, but
responding to Shackey985'a question:
the FAQ claims on its word of honor that the M543 is part of the
M39/G744 tribe.
I have now told more than I know.

LightCorporal said:

I just discovered this thread, so if all the inhabitants are deceased or
still in prison or a rest home, I am not worried until I follow those
(previous) inhabitants.

anywhom,
I hate to sound as though I know what I am talking about, but
responding to Shackey985'a question:
the FAQ claims on its word of honor that the M543 is part of the
M39/G744 tribe.
I have now told more than I know.

Click to expand...

Don't worry- we ain't dead yet. Can't say much about prison, and can't remember about the rest home....

how do you add the 815 to the list

73m819 said:

how do you add the 815 to the list

Click to expand...

done

In reading the TM 9-2320-260-10 it says the M812A1 is a "Rocket Launcher" and the M821 is listed as "Bridge Transport". The M820 could also be added as "Expansible Van".
I have always thought the 812 was a bridge truck, but maybe that is because I read it here.

This also says that the M939's are just rebuilt M809's???

In David Doyle's book Standard catalog of U S Military vehicles. It says that the M809 and M939 were produced side by side briefly as the M939 series production began and the M809 production ended.
Now I ask why would they be building M809 just rebuild into M939's

another vehicle to add to the m39 series, the m246 wrecker. not common but there are some around.

http://www.dtic.mil/cgi-bin/GetTRDoc?AD=AD043820&Location=U2&doc=GetTRDoc.pdf a good amount of info on the m246, i dont know where to put it though

wow where did you find that

typed in M246 in google search, was on the 3rd page. really good info giving a comparison test, and actual results from the test such as its ability to tow and weight lifting at the different crane lengths.

Is there any data on trans swaps? for the 800 series, it is the Spicer 6453. I have seen Spicer 6453A's listed from time to time on the internet. I wonder what the difference is. The 800 could really use a boost of more overdrive.. being rather a slow pig. 16.00x20's seem to solve the 60MPH issue but they bring a few small issues of their own like cost and some driveability.

Can anyone tell me how to find the transfer case ratio of a m939 with a Rockwell T 1134?
I have not found it in the tm.

hi i have a m62 wrecker can anyone give me a part no for 2nd axle pinion oil seal and if there is a filter in the injection pump poor starter

Expanding the M820 Van

I'm doing this mostly from memory. I used M820 vans about 30 years ago.

1. Unhook the safety chains that are attached to the sides of the liftgate.

2. Lower the tailgate to the ground and remove ladders. The liftgate is controlled by two levers. One with a red plastic coated handle and controls the tilt of the liftgate. The liftgate is raised and lowered by attaching a handle to the bent levers under the back corners of the box. To lower the liftgate to the ground, engage the PTO. Tilt the liftgate to its horizontal position by pushing the straight lever with the coated handle towards the rear. The tailgate is lowered by attaching a handle to one of the bent levers and lifting up first to disengage the safety locks. Then lower the tailgate by shoving the lever down.

3. The M820 has four leveling jacks. The leveling jacks go under the corners of the box when expanded. The leveling jacks are not required, but they make the box much more stable. Because of what we used them for, our vans required them to be leveled before we could start working. Remove the 4 leveling jacks and base plates from their storage location behind the cover under the center of the back doorway.

4. You have to open the two back doors to access the cranks to extend the sides.

5. First unlatch the safety latches at the lower corners of the box. I believe that there are cotter pins holding them. At each corner of the box, there is a hinged rod (about 4 feet long with a triangle shaped loop on the end) that is used to secure the box sides when expanded. Keep the rods safely out of the way until the box sides have been extended and cranked tight again.

6. The crank for the doors is supposed to be stored in a bracket fastened to the door (if missing, you can use a large wrench with socket and extender). Put the handle on the hex shaft and flip the lever to disengage the pawl so that the sides can be cranked out. Crank the sides completely out. Flip the hinged side panels out from inside at each corner. These need to be out of the way so that the floor and ceiling panels can be opened.

7. Duck under the opened side and reach up to the center of the box and unlatch the Floor/roof panels.

8. Pull the floor out and down until it rests on the rails that are supporting the extended sides (you might need to get inside the box and push the floor/ceiling panels out.) The roof panel is linked to the floor panel by cables and will flip up at the same time as the floor panel lowers.

9. Now flip the end panels hinged at the corners back in to enclose the box corners. Climb into the box. There is a metal guide that can be extended to help keep the end panels aligned when retracting the box sides.

10. There are 3 hooks (attached at the upper edge of the sidewalls) that should be extended (pointing toward the center of the box). Push up on the ceiling and extend the hooks. These will help guide the ceiling panels when the sides are cranked in.

11. Flip the ratchet pawl. Slowly crank the sides all the way in, paying careful attention to the corner panels. The edges of most of the panels have small metal posts that fit into holes on the wall. These help to keep edges aligned and will mate in the last few inches of retraction. Some of them might jam and need to be bumped into their holes to get the box to close up tightly. If not properly aligned, the edges might leak water, and the box might not close completely. You usually hear a bit of groaning or grinding during the last inch or two of closure.

12. Climb inside the box and fasten the roof latches to the hooks at the upper edge of the sidewalls. There are 3 of them on each side.

13. Now the sides have been cranked in and the roof latches fastened, you should lower the hinged rods on the outside corners of the box and use them to tighten the lower corners down with the safety latches that you first unfastened in the beginning.

14. Install the leveling jacks (if desired) by attaching the baseplate and attaching the top of the jack to a mating flange under the box corners and twisting it to lock it in place.

15. As these vans are prone to leaking, it is best to have a tarp that covers the entire top of the van to keep out the rain. Tie down the tarp to keep it from blowing away in the wind.

When closing up the van for moving, reverse these steps. Attach the ladders to the back doors and secure (if not stored inside the box). Ensure they are kept from moving around by using ropes and/or bungees. I think they have some screws and washers that help to fasten them down to the back doors. To stow the liftgate, raise it and tilt it up vertical. Try to lower it again to ensure that the safety locks have engaged. Disengage the PTO. Attach the safety chains to the of the edges of the liftgate. Stow the lift handles.

The liftgate can be used as a raised platform if some kind of bracing is used under it and a safety chain put around the sides. There might be some holes around the sides of the liftgate for posts linked together by chains. The ladders can then be attached to the sides of the liftgate. Alternately, the ladders can be attached to the side doors.

Lets not forget the M944.

BTW How do I find information on setting up the tenting that surrounds the vehicle? Can't find anything in the TM's. I have the canvases but no poles. There are pole placement placards on the bat wing doors but nothing on setting up the canvases. Our "County Emergency Response Team" want to use the M944 as a command post and setting up the tents for that purpose would be great.

Since the thread is 5-tons, seems it should be broken down into 923, 925, 929 etc. and list the Allison transmissions used T545, T654 etc. I'm no authority to know the variants and haven't searched TM's. Does anyone know how it came to be known as the 939 series instead of the 923 series...which is the basic platform?