Usaf 1970 wm-80

[SgtSnuffy]

Hello,

My name is John and I am new to the club. I recently picked up a retired military truck, it was a USAF POL fuel truck that a farmer removed the tank from.

It has the 478M with Allison automatic and air brakes on all axles.

<br><font color='red'>To view some links or images in this forum your post count must be 1 or greater. You currently have 0 posts. Maybe you should introduce yourself with a new topic?</font><br>

<br><font color='red'>To view some links or images in this forum your post count must be 1 or greater. You currently have 0 posts. Maybe you should introduce yourself with a new topic?</font><br>

The only problem with the truck I have found so far is a melted piston. I'm not sure where or how I will get a replacement. All of the custom piston makers I called said no as soon as I specified "5.125 inch"

<br><font color='red'>To view some links or images in this forum your post count must be 1 or greater. You currently have 0 posts. Maybe you should introduce yourself with a new topic?</font><br>

I hope to save the engine if at all possible, my long term plan is to build a roll-back for it. Would make a nice hauler for taking my tractors to shows.

Thanks for looking!

[FetchMeAPepsi]

Holy cow that truck is "yoooge!" BBv6 said these companies make the pistons. The thread is here
<br><font color='red'>To view some links or images in this forum your post count must be 1 or greater. You currently have 0 posts. Maybe you should introduce yourself with a new topic?</font><br>
Try searching for "pistons" and just look at the fixes other people have used too. You might get a hit or a clue as to where else might have some.

[SgtSnuffy]

LOL, yeah she is a hoss! Thanks for the info I will check it out!

[Funky61]

Welcome SgtSnuffy to the forum!

Thanks for the photos of your GMC 8000 and that scorched piston!
:welcome::coolphotos:

[GMCv6inND]

Yeah, welcome to the club - and you’re only about 30 miles. I had a cab over a little while back, but not w a 478. And it’s an USAF truck too - pretty cool. I worked in vehicle maintenance for USAF at the base but never saw those fuel trucks, just the old Dodges. We did have the old missile erectors or TE tractors, like sits outside of the base, while I was at the base. Wish I would have gotten all the old manuals or parts they had :(
Now, we’ll have to find you a piston!

[SgtSnuffy]

Thanks! Sometimes wish I had been in back in those days, all our trucks from my time are kind of boring.

Would anyone happen to know what model Allison this is? This is the only tag I can find on it and those numbers return zero results in google. It is a six speed with SAE 2 bellhousing and external parking brake on the output shaft. I will grab an over all shot of it tomorrow.

<br><font color='red'>To view some links or images in this forum your post count must be 1 or greater. You currently have 0 posts. Maybe you should introduce yourself with a new topic?</font><br>

[Funky61]

I tried putting that serial number into this site in various forms and it returned nothing, but it states you can give them a call.

<br><font color='red'>To view some links or images in this forum your post count must be 1 or greater. You currently have 0 posts. Maybe you should introduce yourself with a new topic?</font><br>

[SgtSnuffy]

Thanks again for your help! I will give them a call.

[SgtSnuffy]

The plot thickens... Below is the reply from Allison.

John,

Based on the vintage of this transmission, I believe you will need to speak with All Marine Gears. This product was sold to them, so they should have the information that you*are looking for. I have attached the contact information below. Have a great day!

All Marine Gears Contact: Acadian Marine Transmission Inc
106-G Kol Drive
Broussard, LA 70518
337-837-3636

[Funky61]

and another door opens to...another door. This is exciting. :detective:

[Donny]

I do have a full set of 478 pistons brand new in the box if you’re interested

[James]

I performed a web search on the company name and it look like they had change it again. By tracing the phone number it look like they are at this location
<br><font color='red'>To view some links or images in this forum your post count must be 1 or greater. You currently have 0 posts. Maybe you should introduce yourself with a new topic?</font><br>
Hope this is the one. Good luck.

[SgtSnuffy]

Thanks everyone for the help! I sent you a PM Donny.

[SgtSnuffy]

I contacted All Marine Gears, they could not find anything. Suggested I call Pacific Torque and they found it to be a MT-40.

[Funky61]

They still have manuals for them on eBay

<br><font color='red'>To view some links or images in this forum your post count must be 1 or greater. You currently have 0 posts. Maybe you should introduce yourself with a new topic?</font><br> SPLICE.SIM%26ao%3D1%26asc%3D20200520130048%26meid% 3D6b51f2cecf1f4ddaa3beada843d1bf40%26pid%3D100005% 26rk%3D1%26rkt%3D12%26mehot%3Dpf%26sd%3D1539696421 41%26itm%3D401666603671%26pmt%3D1%26noa%3D0%26pg%3 D2047675%26algv%3DSimplAMLv5PairwiseWebWithDarwoV3 BBEV2b&_trksid=p2047675.c100005.m1851

[BobBray]

Air Force had a lot of those. That transmission is probably an MT-40 or 41. Keep checking Ebay, pistons and even complete 478's do show up from time to time.

[SgtSnuffy]

Keeping an eye on eBay, would not mind a complete engine. I found a truck in Montana with a 478. But I know how that would go, I would not have the heart to pull the motor and would have two trucks still needing a 478. Wish I had some good updates for everyone. Just kind of stuck until I get the fire back in her. Thanks again for everyone's support.