In a previous article Eric M wrote about the square-boxy designs of the ’80s… to my disappointment, he didn’t speak enough in regards to what I consider the best “Square Body”. Those who know me well are aware of my strong affection – maybe it’s an addiction – towards what is known as the GM Square Body Truck. What makes this model so great? – You ask … or maybe You didn’t, but I’m going to tell you anyway. LOL.
How about a 19 YEAR PRODUCTION RUN for starters! – Debuting in 1973, the square body truck had a large selection of options and trim packages including third party factory aftermarket options. These trucks really had their roots grounded in 1960-66 with the first generation of the C/K models of GM trucks. The second generation only lasted from 1967-72 leaving the debut of the third generation in 1973 and continuing through 1988-91 under the R/V labeling. Maybe that’s why they weren’t mentioned much in the previous article... they weren’t really from the ’80s, but were offered throughout the entire decade!
GM marketed their third generation design as the “Rounded-Line Pick-ups” but the owners of these trucks have reestablished them to be more commonly known as the “Square body” – and rightfully so, just look at it! They were trimmed as Custom, Custom Deluxe, Cheyenne, Scottsdale, Sierra, and Silverado to name a few. The square body consists of multiple body lengths: the regular cab truck, crew cab (Also known as the 3+3), the Suburban (the longest running non interrupted vehicle model EVER!!! from 1933-present), and the K5 Blazer (or GMC Jimmy).
Designations & Identifiers
The C/K and R/V designations on the trucks are quick ways to differentiate a few key items:
- The C/K was used for the square body from 1973-87 and changed to R/V in 1988.
- Following one of the four letters would have been 5, 10, 15, 20, 25, 30, or 35 depending if it was a Chevrolet or GMC. The “5” was used the Blazer (or Jimmy) while 10 and 15 were the half-ton trucks.
- 20 and 25 covered the three-quarter-ton trucks, and lastly the 30 and 35 consisted of the one-ton trucks.
- In later years those numbers were converted to 1500, 2500, and 3500 (mainly with the R/V series trucks from 1988-91).
- The C and R generally meant the truck was 2WD while K and V meant they were 4WD.
- There was a variety of power train options as well, a 250 cubic inch inline 6 cylinder with “3 on the tree” all the way to the 454 cubic inch big-block with a 4L80E 4 speed lock up converter automatic. Note: The 4L80E was only offered in 1991 for this body style.
- The combinations seemed endless depending on your desire or need! – A factory option was the Camper Special which had a higher GVW than the standard truck.
How about one of those aftermarket factory options I mentioned earlier? The “extended cab.” My research shows that between 1973-1987 only about 2,500 of these trucks had extended cab conversion making them a fabled “great white buffalo”  that very people few have ever seen in person. Custom Vehicles International of Arlington, TX (which is no longer in business) was the primary company offering these conversations and GM even granted the factory warranty after the work was done. The price tag on the extended cab was a staggering $6,000 on top of the cost of the vehicle. Even interior options were available from companies such as Choo Choo Customs in Chattanooga, TN which included captains chairs instead of the second row bench seat and a lifted roof (in the Suburban), upgraded center consoles, and even televisions! Many of these add-ons were of wood based construction and trim – think “Conversion Van” style.
Western Hauler offered a custom back seat for the crew cab that folded down to a bed as well as steel beds utilized on ranches and farms. There were also “cab and chassis” versions that came without a bed and generally a narrowed rear axle.
Special Editions
In case you feel those weren’t enough options, GM also offered multiple “special editions” which include:
- GMC Beau James
- GMC Gentleman Jim
- Chevy Spirit of ’76
- GMC Impact Edition
- (In Canada) the Chevy and GMC Olympic Edition
- Chevy Blazer Chalet and GMC Casa Grande
- GMC Royal Sierra
- Chevy Sport
- GMC Desert Fox
- GMC Sarge
- GMC Indy 500, that’s right, TRUCKS were at INDY!!!! (maybe not racing – but as pace vehicle counts!)
- GMC Amarillo GT (which achieved an amazing 15.6 second 1/4 mile time)
- GMC Mule
- GMC Foxy Sierra
- GMC Street Coupe
- Chevy Rollin’ Rebel (by Choo Choo Customs);
- Chevy Sno Chaser
- GMC California Sundancer
- BIG 10
- and the Indy Hauler
There may have been more undocumented variations as well, as it seemed to be a bit of a “badge engineering“ marketing plan by GM to move more trucks.
Military Use
These trucks were also widely used by the US military as the CUCV (Commercial Utility Cargo Vehicle). For military use, the trucks were upgraded and rated as “5/4” or 1 & 1/4 ton trucks with the exception of the Blazer version. They had multiple designations depending on their set up, including: M1008, M1009, M1010, M1028, and M1031. The military used them for anything from general cargo hauling, command post, fire fighting and even communications!
This generation of GM trucks has been widely used and appreciated. There are many websites and even car clubs dedicated to the Square Body. They were used in Hollywood movies and TV shows, and even recently seen in films passing by as “extras.”
For me and many folks that I know, these trucks hold a special place in our hearts and memories. As a child I spent lots of time riding around in Square Bodies. After I got out of the military I purchased my first one for $175 and in a matter of two weeks my brother and I had it road worthy. Since then, that specific truck has been modified a few times and I have added *many* more to my collection. One day I hope to complete my collection, owning one Square Body from each year 1980-’91 – as I prefer those years the most.
And stay tuned – as I am thinking of building myself one specifically for the track!Â
