VCCA Home Forums TECHNICAL - GENERAL Commercial Vehicles Rare '47 - '48 450 Series GMC COE ?

ebay item 2414670869 , looks like it might be a Rare '47 or '48 GMC 450 Series COE. The seller has it mislabeled as a '53 model. Very few 400 series GMC COE's were built in '47 & '48. What makes them unique is they use the same front axle & fenders as the 350 series COE's used. The '49 - '54 GMC 400 series COE's had wider front axles & wider fenders. This truck seems to have the tall first step as all the 400 series COE trucks had.

I emailed the owner of the COE & found out it is a Rare '47 or '48 GMC 400 series 2 1/2 Ton COE. He also said it's a Tandem axle.

The cab has all of the 1947-48 trade-marks.

1. Fuel tank on frame rail and no cab mounted
tank.

2. The dash photo is a little fuzzy, but it doesn't look like it is notched for the 3- speed gearshift rod like the 1948-53 dashes were. So it may be a 1947 model.

(all the cab models used a common dash panel)

Wish he had posted more pics, none of the bed or rear, etc.

A few questions:

1. How high (approx.) is the bed from the ground?

2. How long is the normal bed?

3. With stock running gear, motor etc. at what speed could you travel?

Thanks lil' johnny,

Looks like the bed is maybe 45+ inches off the road, long, long loading ramps to carry a car.

What about the crusing speed?

On "Diesel Dan" my 1951 COE slide back, because of the 6.17 rear end, 40 MPH is top speed. Any faster than that then the 235 engine sounds like it's going to the moon! :eek: :eek: :eek:

Yeah but any faster and your friend "Lassie' on the leash could not keep up! Or does she ride in the cab on your lap?

Nope! Lassie rides in back. Someone else rides in the cab with me. And, I even let her play with the CB radio too. Guess who? :love: :eek:

Are there other ratios available that can replace the 6.17? Or on the newer 2 tons?

Yes Gator there are other ratios available. The first thing you need to know is what kind of rear you have.

The easyest way to go faster might be to look for a 2-speed pumpkin for your rear. I just did this with my '57 10500 Fire Truck. It had a 7.17 single speed that only allowed a top speed of 53 mph. My rear is a 18,000# Eaton, so I was able to find a "bolt in" 2-speed at the local BIG truck junk yard. The rear I found is a 6.14/8.36 which gives me a really low granny and about 65 mph in high range. I am very satisfied. In doing this swap make sure you get the shift button and harnes if electric or shift button and vacuum valve if vacuum type. There is also a speedometer reduction unit on the back of the speedometer that you will need. It keeps the speedometer in calibration between high and low range.

cool, thanks.

What motor does your '57 have?

A 20% "Brownie" box will do wonders too! :cool2:

???????What??????

Thank you, I learned a lot, and I have a long way to go.

Hey Gator, Weren't you looking for a COE. Did you find one yet.

Hey Gator, my Fire Truck has the 322 Buick V8 with a 2 barrel carb. The 2 speed rear I installed did the trick for me. I can now run highway speeds

As a side note, I am not going to run the truck with water in the 500 gallon tank (this would add 4000 pounds).


I will be driving it to the ATHS Show in NY next week, 400 miles one way! Anybody else going?

Another way to go if you have a long enough driveline is to install a two or three speed Brownie overdrive auxillary tranny, They are pretty common in the oilfield, they use them when there is a PTO winch mounted, also don't forget the powerful 292 Chevrolet Six engine. I have seen them on many firetrucks, tankers and farm trucks from the late 60s on from a one ton panel truck up thru the 6500 series trucks.

:confused:

You mentioned earlier about a V-8 carb. sticking up through the floor board by your right foot.........my 1951 COE slideback has a carb. sticking up through the floor board (right in front of the accelerator pedal) in that very same manner, only it's attached to a six cylinder engine instead! Makes it a little difficult to hit the accelerator pedal with my right foot too! :( :( :( :( :(

Spanky, I haven't found one yet, JYD's COE is the style I really want since it is a slide back, but I'm not going to be too choosey.

Seems like all of them are in the mid-west, I guess we don't use them in the orange groves.

Looks like maybe the newer ones (67 and up) might be better for my needs, but I love the old style more.

I found a '56 2 1/2 or better F*rd BOC (bed/body over cab) from a moving company that had a 22' alum. enclosed over the cab body that was in perfect condition (would have made a good storage garage off the frame) and it ran good w/292 (?) and it had 6 brand new tires, but it was a F*RD and I had to pass ($1800).

Mike, there are other liquids that you could carry in the tank.