I need to buy the transmission cover from Brothers Trucks but, they ask if the application is for a 3 speed or 4 speed trans. I got the truck without a trans so, my question is did the 1948 3/4 ton 3600 come with both or was it only a 4 speed? I'm thinking 4 speed would make sense but I'm not sure.
A 3-speed was standard equipment on 3100 and 3600 1947 Chevrolet trucks. A 4-speed was a Regular Production Option on 3100 and 3600 1947 Chevrolet trucks. A 4-speed was standard equipment on 3800 and larger 1948 and later Chevrolet trucks.
The 1947 three-speed and all four-speed transmissions had a transmission-top through-the-floor shifter - the floor cover had an opening for a transmission shifter.
1948-1955st three-speed transmissions all had a column-mounted shifter and a "flat" transmission-top floor cover.
My uneducated guess would be if your going to put a 3 speed in it order the low plate. If your going to put a 4 speed in it get the tall plate. If your changing to a later automatic you will need the tall plate.ðŸ›
Martin '62 Chevy C-10 Stepside Shortbed (Restomod in progress) '47 Chevy 3100 5 Window (long term project) ‘65 Chevy Biscayne (Emily) ‘39 Dodge Business Coupe (Clarence) “I fought the law and the law won" now I are a retired one! Support those brave men/women who stand the "Thin Blue Line"! Hug a cop! USAF 1965-1969 Weather Observation Tech (I got paid to look at the clouds)
My truck has the 4 speed installed. The plate we are using has a bump to provide clearance for the transmission. This bump has the hole for the shifter. The other plate is flat like in the pix the OP attached. A previous owner replaced the original 3 speed with the 4 speed so the flat one is surplus to my needs.
Have you decided what transmission you will be installing?
After finding out it could be either one, I called Brothers Trucks and ask how I might tell which trans my truck came with. The 4 speed version has about a 6" high flange toward the fire wall while the 3 speed has about 2". It's obvious to me that my truck came with a three speed. I have a 700R and a SBC mocked up as you can see in the photo's. I need to install the radiator support to see if the space between the radiator and the front of the engine is correct to tell if a stock cover will work or not. I think the engine is sitting to low but, it's hard to tell if it is and, if the front to back is good without the heads, intake and water pump on the block. I better put those items to rest before ordering a trans cover.
I installed a 700R4 in my ‘62 C-10 w/3 on the tree and had to use the tall tunnel to provide enough clearance. Required cutting of the firewall a bit so ended up using a fiberglass tunnel from Speedway.
Martin '62 Chevy C-10 Stepside Shortbed (Restomod in progress) '47 Chevy 3100 5 Window (long term project) ‘65 Chevy Biscayne (Emily) ‘39 Dodge Business Coupe (Clarence) “I fought the law and the law won" now I are a retired one! Support those brave men/women who stand the "Thin Blue Line"! Hug a cop! USAF 1965-1969 Weather Observation Tech (I got paid to look at the clouds)
After finding out it could be either one, I called Brothers Trucks and ask how I might tell which trans my truck came with. The 4 speed version has about a 6" high flange toward the fire wall while the 3 speed has about 2". It's obvious to me that my truck came with a three speed. I have a 700R and a SBC mocked up as you can see in the photo's. I need to install the radiator support to see if the space between the radiator and the front of the engine is correct to tell if a stock cover will work or not. I think the engine is sitting to low but, it's hard to tell if it is and, if the front to back is good without the heads, intake and water pump on the block. I better put those items to rest before ordering a trans cover.
"The 4 speed version has about a 6" high flange toward the fire wall while the 3 speed has about 2"." What are they referring to which "has a flange"?
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
Here is a pic of the trimming needed for a 700R4 behind a small block mounted in an AD factory frame. We make our own covers but the 4sp cover should clear or the flat cover could be easily modified. With a Nova clip or an aftermarket MII ifs the trans will clear the floor with just a bit of BFH work on the firewall to toe board pinch weld. All this info is valid only if the engine is mounted in a normal position which is 1" of fan to radiator clearance with a SHORT water pump.
Just get the flat one (3-speed unit, like in your attachment). The four-speed cover has holes you'll have to fill and bumps you'll have to carpet over. Looks like you have adequate clearance, so it'll clear your trans, no sweat.
