M939 series was originally upgrade M809?

"The M939 series was originally designed as an upgrade package for the M809 series trucks." from 5ton faq

So how hard would it be to change the cab and front out from 809 to 939?
And yes I think I would like to try, I have almost new 818 but I am 6'8" and would like to shift without opening the door to make room for my knee!

Csm Davis said:

"The M939 series was originally designed as an upgrade package for the M809 series trucks." from 5ton faq

So how hard would it be to change the cab and front out from 809 to 939?
And yes I think I would like to try, I have almost new 818 but I am 6'8" and would like to shift without opening the door to make room for my knee!

Click to expand...

just buy a 900. the only really common part was the frame and even they were drilled to make the 900 parts fit.

Having driven both trucks. Trust me. There isn't much more room. The drivers seat is still up aginst the door. and the gear shifter for the auto tranny is close to your right leg. Prevew one at a GL auction so you can sit in it and see. It won't make much difference.

Not wanting to change everything just body parts and keep my drivetrain, the 939 cab is 10" wider than 809 so maybe move seat a few inches?

and has anyone heard the new 939 cabs are made of stainless steel?

The M939 series cabs are DEFINITELY not made of stainless steel. I have owned several and can attest to this, and you can look at the thread posted by Chris Stansbury (STEELSOLDIER) showing pictures of this cab floor.

stainless steel?

Csm Davis said:

and has anyone heard the new 939 cabs are made of stainless steel?

Click to expand...

BKubu said:

The M939 series cabs are DEFINITELY not made of stainless steel. I have owned several and can attest to this, and you can look at the thread posted by Chris Stansbury (STEELSOLDIER) showing pictures of this cab floor.

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guess I should have put it "new " or replacement cabs, yes I know that not all M939 cabs are stainless steel but I was told that the "NEW" cabs are.

Dang!! I wish my cab was stainless steel. I haven't heard anything about a stainless replacement cab. That doesn't mean there isn't one, but I like to think that we are "in the know" about 939 stuff around here.

There was a cab with added rollover protection as noted here:

General Accounting Office

The Army decided to
replace M939 cabs when they wore out with ones outfitted with a
rollover crush protection system and also to modify the accelerator
pedal resistance on the A2 variant of the M939. Both TACOM and Army
Safety Center personnel stated that installation of the reinforced
cab rollover crush protection system, while not an industry standard
or required by law, would better protect M939 occupants in the event
of a rollover.

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Does anyone have a drawing of the hardened cabs or at least a way to tell them from the standard cab?

Csm Davis said:

" I have almost new 818 but I am 6'8" and would like to shift without opening the door to make room for my knee!

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I had the same issue, I'm 6'7". The solution was to pull the clutch pedal out and cut a new notch so that we could effectively lower the pedal. You may have to play with it a little to get sufficient free travel and such.

Csm Davis said:

"The M939 series was originally designed as an upgrade package for the M809 series trucks." from 5ton faq

So how hard would it be to change the cab and front out from 809 to 939?
And yes I think I would like to try, I have almost new 818 but I am 6'8" and would like to shift without opening the door to make room for my knee!

Click to expand...

I know some big guys are changing out steering wheels for more room. Also, I would consider altering the shifter a little. Make a cut in the shifter low and see if you can bend it away from you in a direction that gives you more room and is still fully functional, then reweld. I put an overdrive in my jeep and added a shifter in and this worked very well. Looks factory. Also, cut the cushion on the backrest an inch or so to add room. These three simple mods might give you the added room you need.

Thanks for your help at Camp Shelby ! Good luck with your mods !

Ray

I've seen 923's that were overhauled as late as 11-2010, and still had the mild-steel cab. Stainless would be really heavy, and extraordinarily expensive, even for the Govt.

Of all the 900 series 5 tons I saw in the Army (lots), I only saw ONE get a cab replaced because it got rolled. Usually when you had to replace a cab, you could find enough other things wrong the truck to max out the MEL and code it out.

I've seen this guy and he is a good sized ole boy. But I would say go with a 939 series truck. You are right there at the base so you could pick one up pretty easy.

steelsoldiers said:

Dang!! I wish my cab was stainless steel. I haven't heard anything about a stainless replacement cab. That doesn't mean there isn't one, but I like to think that we are "in the know" about 939 stuff around here.

There was a cab with added rollover protection as noted here:

General Accounting Office

Click to expand...

that might explain some of the reinforced cabs that I have seen that didn't have ring mounts or appear to ever had one, but it looked just like the gun truck cabs that I looked at. I have often wondered why they didn't make all the cabs reinforced from the beginning.

Just a thought here but y not just put an auto from a m939 in to your m809?