M880 questions

My friend just drug one of these over to my place for a tune up and to go over it. This truck was donated to our MMMT museum and we would like to use it for that.
I know nothing about this model truck and am wondering what its problem areas are and what should be checked? I just raplaced the fuel line that was leaking and we got it running. It appears to idle a bit high and have a bad exhaust leak. I see new exhaust manifolds for these up for sale often. Are they prone to cracking? I hear a tick tick sound but am not sure if its the manifold yet.
Any info on these trucks would be nice. I am a M37 guy and only owned Chevys that were made in the 70's.
It looks like the 24 volt system is missing. Can you buy new wiring harnesses for these anywhere? Who is a good supplyer for military parts for these trucks?

They are rustbuckets, like most 70's MoPars.

Exhaust manifold shouldn't crack unless it's a slant6, then it will crack without a doubt.

Tailgates are hard to find.

Drivetrain is simple and parts are readily available.

This one is in suprizingly good shape. It was a National guard truck then a airport truck and they never used it. It has the 318 V8. Thanks for the input...

Go to: www.ramchargercentral.com lots of info

Give me a call,
Haven't as yet joined the MMMT, but I do have plenty of info on these trucks.

Thanks Bob. I will get ahold of you when I get back from Findlay. I see your in the UP ahe... If you want some info about the MMMT give Brian Morrison a buzz at bigbeemorrison@juno.com He is our president and we would love to have ya. I see your a Great Lakes member. You ever go to the Clare show? Just wondering if I have met you.
I will have some questions for you as I tare into this truck when I get back.

citizensoldier said:

.....................I see your in the UP ahe... ...........

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Nope, That would the Hiawatha National Forest ( My brother lives there. )

Huron NF is in the N.E. Lower

I knew the Huron forest thing. I actually saw the Escanaba from the guy before you and thought it was part of your post.... Your in our neck of the woods. We could sure use some M880's around the meets and shows..

Did you see this one on epay? Nice truck and price.
http://cgi.ebay.com/ebaymotors/ws/e...d=1,1&item=4639893336&sspagename=STRK:MEWA:IT

My M880 never was 24v and the biggest problem I had to solve was the running / brake lights.

someone who had the truck before me cobbled the wiring to have break lights but no running lights or turn signals in the back.

In my case it was the turn signal switch ( all power to the rear lights goes threw this switch)


parts are easy to find and cheep ( except gas gage sending unit ).

good luck!

I think (memory stinks) only the M882, M882 and M884 had 28V systems. Need to check a manual.

N1265 said:

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parts are easy to find and cheep ( except gas gage sending unit ).

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Saturn Surplus had the sending units very good price too.

I think the last time I asked them for a price for a sending unit it was $80.
(but I could be wrong)

does this seem like the right price to you ?

I tried to get one threw Auto Zone and they told me they could not get them.

someone once told me that you could buy a new one for any mid '70s dodge car for about $20 bucks and re locate the reastate on the pickup tube, and then extend the pickup tube and it would work just as good, ( because the top of them are all the same) However I do not know this to be true (yet)

I like dealing with Saturn... They are very fast and hassel free on their shipping.
I just recently bought a "cargo safty strap" from them and it looks and fits great.
(even though it was listed for a M715)

Wow I thought I paid around $35 for the sending unit

The M881 882 883 884 891 892 Had 24 volt system for the radio equipment.The generator has a 28 volt output.

The electricals are the Achille's heel of the M880. My guages died back in '94; heard there was some gizmo behind the dash that might be at fault, but you know how it is, the hurrier I go the behinder I get. Also had trouble with the charging circuit. Temporary jumper from alternator to battery cable bypassed the problem area and became semi-permanent.
My truck has the gooey black rust-proofing which seems to have worked fairly well.
Change out the fluids and keep things greased and it should be very durable. Antifreeze too, gotta renew the corrosion inhibitors to keep from eating the radiator from the inside out.
Full-time four wheel drive destroyed a set of Kelley made store brand tires in a very short time. Bite the bullet and use good tires.

I am finding the electrical is screwed up. None of the guages work and the military light switch does nothing. No running lights in the cab and the headlights are very dim. It only takes one battery and it starts just fine but because of the dim lights I thought they might be 24 volt bulbs. I am going to pull them and check. All the black out lights are dead too but the brake lights work. Maybe I should just rewire the whole thing? Does anyone have NOS wiring harneses for sale?

power wagon parts has the complete black out light set up for $60. ( I think, but dont quote me on the price) you can do a search on e-bay to get this stuff.

Saturn Surplus has the cab ($175) & front light ($72.50) harnesses.
Grounds are the Mopar failure points, i.e. the taillights ground via the screw that holds the lens/housing to the bed, any corrosion between the diecast & sheet metal = dim or no taillights. 95% of all electrical troubles on these trucks are ground related.
The dash is powered through the amp gauge, if not connected it won't even run.

All lights / operational systems are 12 volt.

Ahhhh. The fog is lifting a bit... I hope to poke around under the dash this weekend. I will let you know what I find. I walked out today and it started right up. So far all I have done is replace some leaking gas lines and charged the battery. The 4 wheel drive seems to work good and there is a small transmission leak.... You think its worth changing the fluid in the tranny? Sometimes it better to just leave her be. Thanks for the info on the wirring harness I will check into it...

When I got mine the tranny leaked from the pan gasket..... I pulled it and replaced the filter and fluid.

It stoped leaking for about 2 months and is leaking again.

good luck