I have a 3100 1/2 ton truck. It has been given new identity, so I cannot determine what MY it is. As 1949 received a lot of changes, which my truck does nnot have it is either MY1947 or MY1948. Jim Carter web gives information: "A GM mistake on the 1947 Advance Design cab is the lack of a water trough on the top of the cowl. By 1948 GM corrected this problem by adding a side to side trough in the cowl." Chevrolet 1949 Engineering Features book says that water drain bead was added to cowl. These two are contradicting. My truck does not have this bead. My trucks SM420 gearbox has been casted 1948, rear end 1950, insrument housings have been changed, so these will not give answer to my question. Do I have MY1947 or MY1948 truck? Any other ways to tell them apart?
Last edited by FinnBolt; Wed May 27 2020 05:39 PM.
28 Years of Daily Driving but now on hiatus. With a '61 261, 848 head, Rochester Monojet carb, SM420 4-speed, 4.10 rear, dual reservoir MC, Bendix up front, 235/85R16 tires, 12-volt w/alternator, electric wipers and a modern radio in the glove box.
I lot of things happen in 72-73 years.... My understanding is the rain gutter was added to the cowl for the 48 model year. But it may have been a running change with some 47s having the gutter and some 48s not. There are other examples out there of running changes. Does the truck have a Serial Number tag/plate on the drivers door pillar? If so, what letters/numbers are on it? Is it a USA built truck or from a European GM division?
Unfortunately it does not have the original VIN tag. That would have been too easy. It doesn't have original engine either, it now has 1962 235 with 848 cylinder head from 1960. It's a 4 speed on the floor, so parking brake location does not help either. When I got it, one door handle opened forwards, the other backwards. I believe correct for '47 to '48 is to open forward and that's the way I made it. Spend two years and many hours and now I'm ready to register that. I would like to get correct year on the Title.
How does park brake not help? In 47 all transmissions have the floor brake including the 4-speed? Is the other floor mounted hardware there or not? A 1947 with a 4-speed will have the lever brake next to the shifter and no floor hardware. A 1948 no matter what transmission will have the floor brake on the DS side (this is small trucks only, big trucks will have the lever brake). If any of this is present you have a 48. https://www.flickr.com/photos/advance-design_parts_co/49632576498/in/album-72157631868452754/
Here are a few differences I found that were exclusive with my 1947 AD truck. Beautiful red truck by the way!
1. All trucks (3 & 4 speed) were floor shift & used GM transmission. 2. The emergency brake was long lever mounted center floor near shifter. 3. The dash & firewall has no provision for shifter. (no rise above steering column) 4. The gauge cluster mounting tabs are unique 1947 only 5. The upper cowl does not have the indentation for the water to run off the sides, instead it will overflow into the engine compartment. 6. 1947 is a one-year only for the long torque tube 62 ½ inches (about 2 ½ inches longer) and did not have the Muncie built transmission. 7. Wind lace molding is crimped in track. 8. Inside door handles push forward to open (1947 only). 9. Serial no’s are EP ( .5 ton), ER (.75 ton) ES (1ton).
Thank you very much for your comments and help! This is what the truck has: 1. 4-speed transmission with e-brake mounted on the side. I did not know, that 1948 4-speed had e-brake on drivers side 2. No provisions or holes for drivers side e-brake 3. Dash has no provisions for shifter 4. Gauge cluster tabs do not fit the instruments, speedo is 90 MPH, so it is from later years 5. No water intendation in the upper cowl 6. Haven't checked the torque tube lenght With thes clues it is indeed 1947 truck
Out of curiosity, if the torque tube is 2" longer where is the extra 2" as the wheel base is the same?