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I bought a 1949 Chevrolet 3600 and this weekend traced the serial numbers -

Distributor boss serial number: AGEA2845
Block Casting #: 3835309
Manifold Casting #: 3835580

I was hoping someone on this forum might be able to help me decipher what I have in the way of engine date, type and plant.

Thanks. Todd

Distributor boss serial number: AGEA2845
GEA is a 1949 truck engine serial number prefix.
I do not know what the leading "A" refers to?

2845-1000 = 1845th 235 engine out of the Flint MI engine plant that model year

Block Casting #: 3835309
1948-1949 235 (low pressure 235 with two bolt valve cover?)

Is there an Engine Serial Number stamped into the flat-ledge in block to the rear of the distributor?

Find and post the head/block casting codes & date casting codes

Interesting .... and thanks Tim. When I bought the truck it was advertised as a 216 engine. Did Chevrolet put 235's in the 1949 3600 trucks? Or, does this suggest the original engine was swapped-out for a 235?

Before making further speculation, Todd, find and post the date casting codes and the engine serial number.

The 235 was an option in the 4000 series trucks, and it was the standard engine in trucks larger than 4000 series.

The 235 engine was not an option in 3100-3800 trucks in that year.

The serial number AGEA2845 is what I found on the flat plate just to rear of the distributor. I can't get to the date cast number without removing the starter.

A = RPO-225 (Heavy Duty Engine)
GE = year/model (1949 4000 & 6000 Series)
A = Flint engine plant
2845 = unit number starting with 1001

Looks like you have a 235 out of a 1949 4000 series truck.

Mike B

Thank you Mike. Good to know what engine I've got. I Appreciate your help.

I find the "Chevrolet Pickup Red Book" (Motorbooks International) useful although there are gaps.

In spite of that, the 1949 under Engine Suffixes for the 3600/3800 says :

AGCA - 216.5 I-6 1bbl 90 hp- three/four speed manual

It has the same description for AGCM but does not mention AGEA.

The AGCA is not further broken down. I assume the AGCA would have been stamped behind the distributor but as a prefix not a suffix.

Maybe, swapping the "C" for an "E" would be for a 235. Were 235's in Loadmaster trucks, not Thriftmasters?

I checked out EBay and just bought another copy of the Red Book for $6.38 (free ship) that I'll give to my brother-in-law.

By the way, your 3600 would have cost $1372 list back in the day.

That book is only giving you pickup info...

Prefix AGCA

AGC = 1949 3600/3800 Series 216
A = Flint Engine Plant, M = Tonawanda Engine Plant


Prefix AGEA

AGE = 1949 4000 Series with RPO 225 Heavy Duty Engine (235)
A = Flint Engine Plant, M = Tonawanda Engine Plant

Mike B

Mike,

What's RPO mean? Thanks!

RPO stands for Regular Production Option and is General Motors’ standard coding for vehicle configuration options. What do RPO Codes Designate? Each RPO code is a combination of three alphanumeric characters (like Z71) that refers to a specific option or modification to the vehicle as built during production.
Decoding General Motors RPO Codes | NewGMParts.com
www.newgmparts.com/decoding-general-motors-rpo-codes

Thanks, Rust,

I've also seen that in the 1948 Restoration Guide and wondered. Thanks for the link.

RR - I hope you do not mind me adding:

RPOs were options that were ordered when the truck was ordered - they were installed at the factory.

Accessories were/are "options/items" that can/could be ordered by the dealer or by the owner, and, they could be installed by the dealer or by the owner.

One of the more famous RPO codes was for the 1967 Camaro, it was RPO-Z28, which was a high performance package...and the rest is history!

Mike B

Mike-
Out of curiosity, with the AGE designation, how did you determine my engine came from a 4000 vs 6000 series truck?

The GEA & GEM are 6000 Series engines, to get that HD engine in a 4000 Series you had to order RPO-225 which added "A" as a prefix to the 6000 series code making it AGEA or AGEM.

Mike B

Does the RPO designation have any significance/value over other 235 engines? Or, is this simply how the engine was ordered to get a 235 in 4000 series truck?

The engine code was altered by adding the "A" prefix so the maintenance/service guys would know it's a 235 and not the regular 216 when ordering replacement parts. Nothing special about it...

Mike B