Chevrolet Light Trucks — C/K Pickups, Blazer, Suburban (1960–1982)

Covers Chevrolet C/K conventional-cab light trucks (C10/C20/C30 2WD, K10/K20/K30 4WD), the K5 Blazer (1969–82), and the Suburban (Carryall) built on the same chassis. GMC badge-mates (C/K 15–35, Jimmy, Suburban) share almost every code here — see ../gmc/README.md for the GMC-specific trim RPOs. El Camino is covered in the Chevelle doc; step-vans and medium-duty (50/60/80-series) are out of scope.

Code systems:

• 1960–1962 — options were ordered under Chevrolet's older numeric option-number system (3-digit RPO numbers, e.g. RPO 431); the alphanumeric RPO codes below do not apply. These numeric codes are documented in the GM Heritage factory truck data books (see the 1960–62 table below, sourced from the T1 kits).
• 1963 onward — Chevrolet adopted the corporate three-character RPO system (letter + two digits, later letter-letter-digit); codes appear on build sheets and window stickers (348-409.com).
• 1973 onward — the RPO content of each truck is listed on the glovebox-lid / fender-mounted option label (predecessor of the SPID sticker), which is the usual way owners read these codes today.

Confidence labels follow the repo convention: confirmed = 2+ independent sources agree on the code meaning, single-source, disputed = sources disagree (disagreement noted). Several GM RPO codes were reused with different meanings in later decades; where a modern list disagrees only because of code reuse, that is noted rather than marked disputed.

Years 1960–1962 {#year-1960}

First years of the C/K ("new-look" independent-front-suspension) generation; the Apache 10/20/30 series names were used through 1961. These trucks predate the alphanumeric RPO system: factory options were ordered under a 3-digit numeric option-code system. Enthusiast sites had not transcribed these, but the GM Heritage factory data books (T1 kits) list them inline. The confirmed numeric codes below are drawn from the 1960 kit (which references each code by number in its engineering notes); the same numeric system continued through 1961–62. Front suspension for 1960–62 used torsion bars (RPO 329/332), coil springs arriving for 1963.

Note: the 1960 kit's numeric codes are chassis/heavy-duty–heavy (springs, axles, frame, brakes) because those are the codes cross- referenced in its engineering tables; the appearance/comfort numeric codes (Custom Cab, De Luxe heater, radio, Powerglide, 4-speed) also existed but appear only in per-model option tables whose OCR column alignment is unreliable, so they are not asserted here. The 1962 kit confirms the numeric system continued (e.g. Positraction, Custom Chrome, Powerglide and 4-speed all carry 3-digit numbers on its per-model pages).

Years 1963–1966 {#year-1963}

Chevrolet's alphanumeric RPO system was in use from 1963. The codes below are division RPOs documented as in use 1963+ whose truck application is corroborated by their continued presence in the 1967–72 truck list. For 1963 the front torsion bars (1960–62) were replaced by coil springs; coil rear suspension remained standard on 2WD 1/2-tons (leaf rear optional — see G70 in the 1967–72 section). The 230 I6 replaced the 235 for 1963; the 292 I6 arrived the same year.

The tables below were substantially rebuilt from the GM Heritage factory truck data books (T1 kits). The 1965 kit carries a clean single-line "OPTIONAL EQUIPMENT INDEX" (pp.19–20) and is the authoritative source for these years; the 1964 kit's "REGULAR PRODUCTION OPTIONS" index (pp.15–16), the 1966 kit's optional-equipment tables (p.24), the 1963 kit (p.6) and the 1967 kit (p.21) corroborate. Rows carrying an <span class="doc-cite">⛭ GM Heritage — …</span> citation are factory-confirmed.

Two disputes the kits resolve:

• N33 was the Sports-Styled steering wheel, not Comfortilt, in 1963–66; Comfortilt was N34. (N33 was reused for Comfortilt from 1967 on — the source of the confusion.)
• Tinted glass in 1963–66 used A09 (Soft-Ray, windshield only) and A11 (Soft-Ray, all windows), not A01/A02. A01/A02 are later-era (1967+/1973+) codes carried back in error.

Trim, appearance & body

Engines & drivetrain

Axles, suspension, brakes

Chassis, electrical, cooling, interior

Remaining gap: the kit Z-series on 1965 p.20 is dominated by GVW rating plates (Z56 = 15,000 lb, Z59 = 21,000 lb, Z70 = 7,800 lb, etc.) and 348/409 big-block engine codes (L39/L40) that are medium-duty and out of light-truck scope. Wood/steel bed-floor and Custom Cab trim numbers for the earliest 1963 order guide remain thin.

Years 1967–1972 {#year-1967}

"Action Line" generation. Year milestones affecting option availability: 1967 new body, small rear window standard; 1968 federal side-marker lamps added, 50th-anniversary paint promotions; 1969 K5 Blazer introduced, 350 V8 replaces 327; 1970 GMC Jimmy arrives; 1971 front disc brakes become standard (J62 optional before), Cheyenne trim introduced, AM/FM available; 1972 last year, Cheyenne Super (YE9) full year. Trim ladder: base Custom, Z61 Custom Appearance + Z62 Custom Comfort & Convenience ("Custom Deluxe" when combined), Z84 CST (Custom Sport Truck) 1967–70 → Cheyenne 1971–72, YE9 Cheyenne Super 1971–72.

Medium-duty-only codes (2-speed axles above 11,000 lb, air brakes, Clark/Spicer 5-speeds, step-van bodies, 17.5–22 in wheels) are omitted as out of scope.

Trim & option packages

Blazer / Suburban body

Engines

Transmissions & clutch

Axles, suspension, brakes

Chassis, electrical, cooling

Body, interior, appearance

Years 1973–1982 {#year-1973}

"Rounded Line" (square-body) generation, introduced 1973 and built past this document's 1982 cutoff (through 1987/91). Year milestones: 1973 new body, Suburban gains 4 doors, Crew Cab introduced; 1975 trim renames (Custom Deluxe base / Scottsdale / Cheyenne / Silverado; YE9 = Silverado); 1976 Blazer switches to steel half-cab convertible top; 1977 power windows/locks available, TH400 relisted as M40; 1978 LF9 350 Olds diesel offered (C10/C20, Blazer, Suburban); 1980 V22 chrome grille standard on Silverado; 1981 facelift, 305s (LE9/LF3) replace some 350 applications, G80 becomes Eaton automatic locker; 1982 6.2L Detroit diesel (LH6/LL4) introduced, 700R4 4-speed automatic (MD8/MX0) and 4-speed OD manual (MM7) arrive, Z84 trim discontinued after 1981.

Trim ladder (Chevrolet): base Custom (1973–74) / Custom Deluxe (1975+); Z62 Custom Deluxe (1973–74) → Scottsdale (1975+); Z84 Cheyenne (1973–81); YE9 Cheyenne Super (1973–74) → Silverado (1975+). See gmc/README.md for the GMC names on the same codes.

Trim & option packages

Engines (light-truck, within 1973–82)

Transmissions

Axles, suspension, brakes, chassis

Body, interior, appearance

Blazer 1973–82: the K5 (and 2WD C5 Blazer, 1970–75 only as C10 Blazer chassis) uses the same option book; the removable fiberglass full top continued to 1975, replaced by a removable half-top over a steel half-cab for 1976+. Blazer-specific codes beyond the shared list (e.g., soft-top variants) were not separately verifiable online — minor gap. Suburban 1973–82: gains AS3-related rear seating, C69-style rear air, E55-lineage rear panel-door/tailgate choice; codes shared with pickups.

Sources

Factory kits (T1)

GM Heritage Center vehicle-information kits, OCR'd (Tier-1, factory primary). These are the source for every <span class="doc-cite">⛭ GM Heritage — …</span> citation above and were the basis for rebuilding the 1960–62 and 1963–66 sections. The 1965 kit's clean single-line OPTIONAL EQUIPMENT INDEX (pp.19–20) is the most reliable; the 1964 REGULAR PRODUCTION OPTIONS index (pp.15–16) and 1966 optional-equipment tables (p.24, plus the A/C table p.20) split their code/description into interleaved columns, so only cleanly-aligned rows were extracted. Kits used this pass:

• heritage-ocr/chevrolet-trucks/1960-Chevrolet-Truck.txt — 1960 numeric option codes (inline engineering references)
• heritage-ocr/chevrolet-trucks/1963-Chevrolet-Truck.txt — 1963 per-model optional-equipment tables (p.6)
• heritage-ocr/chevrolet-trucks/1964-Chevrolet-Truck.txt — 1964 Regular Production Options index (pp.15–16)
• heritage-ocr/chevrolet-trucks/1965-Chevrolet-Truck.txt — 1965 Optional Equipment Index (pp.19–20), per-model tables (p.8)
• heritage-ocr/chevrolet-trucks/1966-Chevrolet-Truck.txt — 1966 optional-equipment tables (pp.8, 20, 24)
• heritage-ocr/chevrolet-trucks/1967-Chevrolet-Truck.txt — 1967 trim/option tables (p.21), corroborating 1966 carryover

Primary (fetched and transcribed):

• 73-87chevytrucks.com RPO lists (A–L, M–8): http://www.73-87.com/7387info/7387rpo1.htm and http://www.73-87.com/7387info/7387rpo2.htm
• 73-87chevytrucks.com trim level guide (Ken Lewis): http://www.73-87.com/7387info/7387trimlev.htm
• Out In The Shop — 67-72 Chevy/GMC truck RPO codes: http://outintheshop.com/options.html
• 348-409.com — Chevrolet R.P.O. codes 1963–1970s: https://www.348-409.com/rpo1.html
• Halderman GM RPO code list (PDF): https://jameshalderman.com/wp-content/uploads/2019/04/RPO_Codes.pdf
• GM RPO codes & descriptions master list (PDF): https://rparts-sites.s3.amazonaws.com/dec399b0838336997484042ed2af1004/design/rpoCodes.pdf

Secondary (context, via search excerpts):

• GM Authority — GMC Sierra Grande / High Sierra / Sierra Classic history: https://gmauthority.com/blog/2025/10/gmc-sierra-grande-high-sierra-and-sierra-classic-history-alley/
• Wikipedia — Chevrolet C/K (second generation), Chevrolet K5 Blazer: https://en.wikipedia.org/wiki/Chevrolet_C/K_(second_generation) , https://en.wikipedia.org/wiki/Chevrolet_K5_Blazer
• GM Heritage Center vehicle info kits online (image-scan PDFs): https://www.gmheritagecenter.com/docs/gm-heritage-archive/vehicle-information-kits/Chevrolet-Trucks/1966-Chevrolet-Truck.pdf — now available OCR'd; see the Factory kits (T1) list above.

Known gaps: 1960–62 numeric option codes are now partially filled from the 1960 factory kit (chassis/HD codes); the appearance/comfort numeric codes and the earliest 1963 order-guide bed-floor/Custom Cab trim numbers remain thin. Blazer soft-top RPOs 1973+; some paint/interior trim number codes (e.g., 12L, 77V) omitted as year-specific color codes. Bot-blocked during compilation (leads for future passes): 67-72chevytrucks.com forum master list (thread t=387040), ck5.com resources, gmsquarebody.com threads, CJ Pony Parts 1967–86 RPO page.