Help me on engine code

[3x2GTO]

The 454 in my k30 has the prefix CFS followed by the vin that matches the truck. I can't find CFS anywhere on the internet. Can someone help? The reason I ask is because I have the truck for sale locally and a buyer thinks the truck was originally an automatic instead of the 4 speed that's in it now. I'm not sure and I need to know what I'm selling. Thanks!

[geezer#99]

Post a pic of the pad.

[Palf70Step]

What year truck? Also do you mean vehicle VIN or engine VIN?

[3x2GTO]

Originally Posted by Palf70Step

What year truck? Also do you mean vehicle VIN or engine VIN?

1985 chevy k30

[3x2GTO]

Here's a picture of the pad and the vin plate on the dash. I know it's the original engine to the truck, but I'm wanting to know if it was originally an automatic or manual. The suffix CFS would tell that info, but I can't find that code anywhere?

[hatzie]

Originally Posted by 3x2GTO

Here's a picture of the pad and the vin plate on the dash. I know it's the original engine to the truck, but I'm wanting to know if it was originally an automatic or manual. The suffix CFS would tell that info, but I can't find that code anywhere?

That's a partial VIN not the engine code. The last 8 digits of your VIN are FS117369

The engine code letters will be a suffix (the last digits) not a prefix (the first digits).

The SM465 transmission ID is stamped on the rear face of the transmission case, below the rear retainer.

[3x2GTO]

Originally Posted by hatzie

That's a partial VIN not the engine code. The last 8 digits of your VIN are FS117369

The engine code letters will be a suffix (the last digits) not a prefix (the first digits).

The SM465 transmission ID is stamped on the rear face of the transmission case, below the rear retainer.

Thanks, I'll check that out and post results.

[SKR]

Maybe I'm dumb and missed something obvious, but why are we looking at the motor to figure out whether it was a manual or automatic instead of RPO codes in the glovebox?

[MJN]

Is it hydraulic clutch or mechanical? If its mechanical the z-bar bracket on the frame under the driver's side floorboard should be rivited to the frame. Post some pictures of the truck and setup- that will help immensely with determining if it was swapped or not.

[geezer#99]

Originally Posted by SKR

Maybe I'm dumb and missed something obvious, but why are we looking at the motor to figure out whether it was a manual or automatic instead of RPO codes in the glovebox?

Because the suffix code will tell you which trans it came with.

[geezer#99]

Do you have a quadrajet carb?
The carb number and drivers side linkage can indicate trans type.
That CFS isn’t a suffix code.
Where is that pad located?

[3x2GTO]

Yes Q jet on a performer intake, but the carb is from a 1980 454, not original to the truck. The pad is a machined part of the block, where the pass side head and block meet, right behind the alternator. The stamped VIN on the pad looks a little hokey to me, I'm guessing the CFS code may be a warranty block? I owned BBC chevelle with a warranty block and it was stamped CE. Is there a VIN on a manual truck transmission? If so where would I look?

[geezer#99]

Looking closer I see it’s the right pad. A suffix would be further left on the pad.
I too had a bbc with the CE code. It was a warranty LS6 block. Original had 3 bad pistons.
What trans?

[3x2GTO]

the truck has the sm465, the CE chevelle had a muncie

[3x2GTO]

Oh well, if it was converted to a manual someone did a very nice job! I'll poke around on the truck this weekend and see if I can come up with anything. Thanks all for the help.

[geezer#99]

There might be a pad on the trans somewhere with a partial vin.
I know m21 and m22’s had one.
Exactly where I can’t remember.

What makes this buyer think it was an automatic?
There’s a lot of stuff needed to change trans. Steering column, wiring, brackets etc.

[3x2GTO]

Originally Posted by geezer#99

There might be a pad on the trans somewhere with a partial vin.
I know m21 and m22’s had one.
Exactly where I can’t remember.

What makes this buyer think it was an automatic?
There’s a lot of stuff needed to change trans. Steering column, wiring, brackets etc.

That IS a lot to change out and this truck even has a tilt wheel. I've owned a bunch of square bodies and this is the only tilt / 4 speed combo I've come across. I have no idea where the buyer got the idea it was originally an automatic, probably trying to buy it for less.

[geezer#99]

Spid in glovebox isn’t always the one that came with the truck. You can buy repro ones. And glove box doors can easily be swapped.
Suffix codes and vin stamps on the motor are much more accurate. Harder to fake. And not normally re-stamped.
I don’t think the op is concerned with the buyer bs, he just wants to know for himself.

Are you enjoying the snow SKR?

[Palf70Step]

Every engine code that starts with CF, that I can find, are small block codes. No CFS as you mentioned. Can you get the block casting numbers off the side of the engine, which could help narrow it down some.

[Keith Seymore]

Originally Posted by Palf70Step

Every engine code that starts with CF, that I can find, are small block codes. No CFS as you mentioned. Can you get the block casting numbers off the side of the engine, which could help narrow it down some.

Originally Posted by hatzie

Decode is from the 1985-1987 GM Light Truck parts books.

Engine VIN:CFS117369
C= Chevrolet
FS117369 Matches last 8 of vehicle VIN.

C = Chevrolet
F= 1985 Model year
S = St Louis assembly plant
117369 = sequential portion of VIN

Hatzie is absolutely correct.

K

[hatzie]

Email the VIN to GM customer service.
They'll send you a PDF in a couple days with a detailed list of factory installed options.

---------------form email---------------

Email to: socialmedia@gm.com
Subject: Build sheet request

Hello,
I read that I could request a build sheet on the 67-72 Chevy Truck Forums.
I'm hoping you can provide me with a build sheet for My GM Light Truck.
1985, Chevrolet, K30, VIN: 1GCHK34W3FS117369

Thank you,


---------------------------------------------------

[3x2GTO]

Thanks for the link, I'll try the GM email thing or you can if you want? Had a few minutes tonight and took these pictures. I'm sure I didn't find the right place on the trans for the VIN, but here's the characters I saw. The spid and my buyer are both gone, just wanna know for sure what I'm selling so I can answer the next buyer's questions.

[hatzie]

Decode is from the 1985-1987 GM Light Truck parts books.

Truck VIN:1GCHK34W3FS117369
1= USA build
G= GM
C=Chevrolet
H=9,001-10,000lb brakes & suspension
K=Reg cab 4WD
3=30 series (1-ton)
4=2 door cab
W=LE8 7.4L 4bbl V8
3=checksum digit
F=1985
S=St Louis
117369 is the production sequence number

Engine VIN:CFS117369
C= Chevrolet
FS117369 Matches last 8 of vehicle VIN.

The three letter 1985 7.4L engine suffix codes will not tell you any more than the VIN. I looked up the ones listed in the parts books. All you can find out is they were the LE8 RPO in a 3/4 or 1-ton chassis trucks... VIN W... The alphanumeric prefix to the three letter engine code would be the build date... again not terribly informative.

Transmission ID code:N5P24
N=4 Speed Muncie CH465
5=1985
P=September
24=24th day of month

Some observations. Take them for what they're worth.
It looks like the numbers match your truck with some oddities.

1. The stamped numbers on the engine don't look like GM factory stamps. The 1s have feet, the top loop of the 3 is not rounded, the upright on the 7 has a jog at the bottom, and the rounds on the 9 & 6 are oddly formed straight lines not circles. They also look like shorter and narrower characters than the stamps on the transmission. The GM stamps I've seen are usually block characters with rounded numbers like the ones on your transmission. The casting number would possibly clear this up or it might muddy the waters.
2. The transmission is a 1985 4 speed truck transmission but the build date is September 24th. September 24th would normally be into the next production year... My 2005 K2500 was built in September of 2004. I'm not sure where the cutoff was in 1985. A build sheet from GM would tell the production month and year. If the truck was built prior to the transmission stamp date then the transmission was changed at some time in its' life. Not shocking on a full ton 4wd work truck.

The 1985-1991 hydraulic clutch setup isn't the easiest thing in the world to retrofit.

Look on the LH frame rail next to the bellhousing. If this was originally an automatic truck it'll probably still have the sheet metal retainer for the shift linkage pivot ball riveted on the frame.

Not sure any of this matters that much on a 1985 K30. I'm also not sure why someone would go to the trouble of re-stamping the engine pad in a 1 ton truck unless it was possibly done as a dealership re-power at some time or it was a hot engine or a machine shop that decked the block actually re-stamped it...?

Get the build sheet. I'm interested in what the story might be.

[3x2GTO]

Originally Posted by hatzie

Decode is from the 1985-1987 GM Light Truck parts books.

Truck VIN:1GCHK34W3FS117369
1= USA build
G= GM
C=Chevrolet
H=9,001-10,000lb brakes & suspension
K=Reg cab 4WD
3=30 series (1-ton)
4=2 door cab
W=LE8 7.4L 4bbl V8
3=checksum digit
F=1985
S=St Louis
117369 is the production sequence number

Engine VIN:CFS117369
C= Chevrolet
FS117369 Matches last 8 of vehicle VIN.

The three letter 1985 7.4L engine suffix codes will not tell you any more than the VIN. I looked up the ones listed in the parts books. All you can find out is they were the LE8 RPO in a 3/4 or 1-ton chassis trucks... VIN W... The alphanumeric prefix to the three letter engine code would be the build date... again not terribly informative.

Transmission ID code:N5P24
N=4 Speed Muncie CH465
5=1985
P=September
24=24th day of month

Some observations. Take them for what they're worth.
It looks like the numbers match your truck with some oddities.

1. The stamped numbers on the engine don't look like GM factory stamps. The 1s have feet, the top loop of the 3 is not rounded, the upright on the 7 has a jog at the bottom, and the rounds on the 9 & 6 are oddly formed straight lines not circles. They also look like shorter and narrower characters than the stamps on the transmission. The GM stamps I've seen are usually block characters with rounded numbers like the ones on your transmission. The casting number would possibly clear this up or it might muddy the waters.
2. The transmission is a 1985 4 speed truck transmission but the build date is September 24th. September 24th would normally be into the next production year... My 2005 K2500 was built in September of 2004. I'm not sure where the cutoff was in 1985. A build sheet from GM would tell the production month and year. If the truck was built prior to the transmission stamp date then the transmission was changed at some time in its' life. Not shocking on a full ton 4wd work truck.

The 1985-1991 hydraulic clutch setup isn't the easiest thing in the world to retrofit.

Look on the LH frame rail next to the bellhousing. If this was originally an automatic truck it'll probably still have the sheet metal retainer for the shift linkage pivot ball riveted on the frame.

Not sure any of this matters that much on a 1985 K30. I'm also not sure why someone would go to the trouble of re-stamping the engine pad in a 1 ton truck unless it was possibly done as a dealership re-power at some time or it was a hot engine or a machine shop that decked the block actually re-stamped it...?

Get the build sheet. I'm interested in what the story might be.

I'll check the frame rail for the automatic retainer, not sure on a sm465 trans, but muncie 4 speeds with date codes from Sept thru Dec were actually built the prior year. Maybe the same on this one? I'll get the sheet and post results. Thanks!

[hatzie]

I just saw your comment about the manual transmission tilt column...
Tilt or not the column is an 85-91 part.
Tilt with a manual transmission means it was special ordered. That's a rare piece. I doubt someone went to the trouble of finding a manual tilt column on an auto to manual swap of a K30.