Since this comes up a lot, I thought I'd lay it out in words and pictures. Purists please note I am glossing over some details and trying to give the general idea, so don't get your bowtie boxers in a bunch. Also remember I'm only discussing the 73-87/91 trucks of the "old" here, i.e. no 1988-91 IFS style, and only fullsize trucks -- no baby Blazers (S-10, etc.)
Executive Summary
In short, the "K5" is just a badge on the Blazers. Their actual model number is something else.
Numbers
1/2 ton trucks -- including pickups, Suburbans, and Blazes & Jimmies -- are called "10", "15" or "1500" series, depending on year. [Why the General called the Blazers "5" we'll never know.]
3/4 tons -- pickups and Suburbans only, as Blazers were never offered in 3/4 -- are correspondingly "20", "25" or "2500".
And 1-tons (only pickups) are "30", "35" or "3500."
The 10/20/30 designations were used by Chevy through 1988, after which they used 1500/2500/3500.
Series 15/25/35 were GMC's through 1978, after which they switched to the 1500/2500/3500.
So a '74 Blazer is a 10 series, a '74 Jimmy a 15, and either from 1990 is a 1500. With me so far? Good.
Letters
2WD trucks were prefaced with "C" and 4WD with "K", through 1986. For 1987-1991, the 2WD trucks were prefaced with "R", and 4WD with "V". (The "new" body style trucks got the C/K designations.)
This means that a 1974 2WD Blazer is a C10, "C" for 2WD and "10" for half-ton, and the 1990 Blazer is 4WD, so it's a V1500. [Did I mention that 2WD Blazers stopped in 1982?]
You'll see the old body style trucks for 1987-1991 referred to as "R/V" trucks for this reason. It's nothing to do with recreational vehicles, but delineates them as the old body style as opposed to the new IFS style. (R/V trucks included the Blazer/Jimmy, Suburban, crewcab pickups, and some cab-and-chassis trucks.)
Details
The full GM model for any given truck is even more complicated, as it indicates body style (Blazer, Burb, regular or four door pickup, bed type) and wheelbase. Depending on year, it would be something like C10103 or K10516. For examples, here's some material used for dealer training in 1977. First, the Blazer:
...and here are the various pickup options:
Hopefully that all makes sense, although it's somewhat overwhelming.
If you want more information and/or are interested in the newer trucks, say, check out my Brochures pages. The pages above are from that site, and there's tons and tons more information, straight from the horse's mouth.
In conclusion, note that while us CK5-er's are knowledgeable Chebby nerds, you'll find lots of people -- and the parts houses -- don't know any better. MANY for-sale ads will list a "C20" that turns out to be 4WD (or for that matter, 1/2 ton
) and the like, so take what you read with a grain of salt. Even Helm, the folks that print the factory service manuals, get the letter/series designations wrong sometimes, and the parts houses will ask you about a 1990 "K1500" Blazer or whatever other nonsense.
Now that you know about the various options, you can prolly pick the right option on the computer, so that the pimply-faced idiot at the parts house doesn't have to know anything
-- A
Executive Summary
In short, the "K5" is just a badge on the Blazers. Their actual model number is something else.
Numbers
1/2 ton trucks -- including pickups, Suburbans, and Blazes & Jimmies -- are called "10", "15" or "1500" series, depending on year. [Why the General called the Blazers "5" we'll never know.]
3/4 tons -- pickups and Suburbans only, as Blazers were never offered in 3/4 -- are correspondingly "20", "25" or "2500".
And 1-tons (only pickups) are "30", "35" or "3500."
The 10/20/30 designations were used by Chevy through 1988, after which they used 1500/2500/3500.
Series 15/25/35 were GMC's through 1978, after which they switched to the 1500/2500/3500.
So a '74 Blazer is a 10 series, a '74 Jimmy a 15, and either from 1990 is a 1500. With me so far? Good.
Letters
2WD trucks were prefaced with "C" and 4WD with "K", through 1986. For 1987-1991, the 2WD trucks were prefaced with "R", and 4WD with "V". (The "new" body style trucks got the C/K designations.)
This means that a 1974 2WD Blazer is a C10, "C" for 2WD and "10" for half-ton, and the 1990 Blazer is 4WD, so it's a V1500. [Did I mention that 2WD Blazers stopped in 1982?]
You'll see the old body style trucks for 1987-1991 referred to as "R/V" trucks for this reason. It's nothing to do with recreational vehicles, but delineates them as the old body style as opposed to the new IFS style. (R/V trucks included the Blazer/Jimmy, Suburban, crewcab pickups, and some cab-and-chassis trucks.)
Details
The full GM model for any given truck is even more complicated, as it indicates body style (Blazer, Burb, regular or four door pickup, bed type) and wheelbase. Depending on year, it would be something like C10103 or K10516. For examples, here's some material used for dealer training in 1977. First, the Blazer:
...and here are the various pickup options:
Hopefully that all makes sense, although it's somewhat overwhelming.
If you want more information and/or are interested in the newer trucks, say, check out my Brochures pages. The pages above are from that site, and there's tons and tons more information, straight from the horse's mouth.
In conclusion, note that while us CK5-er's are knowledgeable Chebby nerds, you'll find lots of people -- and the parts houses -- don't know any better. MANY for-sale ads will list a "C20" that turns out to be 4WD (or for that matter, 1/2 ton
) and the like, so take what you read with a grain of salt. Even Helm, the folks that print the factory service manuals, get the letter/series designations wrong sometimes, and the parts houses will ask you about a 1990 "K1500" Blazer or whatever other nonsense.Now that you know about the various options, you can prolly pick the right option on the computer, so that the pimply-faced idiot at the parts house doesn't have to know anything
-- A
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I don't do so much for the older trucks, but there's some paperwork for them on the site.
