K5 Blazer

Built to Beat the Bronco

Chevrolet's full-size Blazer was conceived to fight the Ford Bronco, and its answer was to shorten a pickup rather than design a small dedicated 4x4. GMC sold the same truck as the Jimmy. When GM redesigned its full-size truck line for 1973, the Blazer moved with it onto a new chassis with fresh, squared-off styling. The second generation would run nineteen model years, and the question it kept answering was how much pickup a sport utility could share and still feel like a weekend toy.

The Full Convertible Years, 1973-1975

The 1973-1975 trucks kept a fully removable top, cab roof included, and 1975 was the last year a Blazer could be opened all the way. The standard engine was the 250 cu in six at 100 hp net, with a 292 six, a 307 V8 at 115 hp and a 350 at 155 hp on the 1973 option list, and a 400 V8 by 1975. How power reached the ground in these first years is where the sources part company. Wikipedia says every 1973-1980 Blazer used the gear-driven, part-time NP205 transfer case. A ck5.com club table says the 1973 trucks had a full-time system, listing the NP203 with automatics, and an insurance-industry history says full-time four-wheel drive came with the automatic V8 for 1973. The NP205 statement cannot be true of every truck if the full-time cars existed.

The Half-Cab, 1976-1980

For 1976 GM carried over the pickup's steel cab roof and made only the rear section removable, a fiberglass-reinforced plastic shell that bolted down with 16 bolts. None of the sources consulted gives GM's reason for the change. The half-cab sold: tabulated output rose from 74,389 for 1976 to 90,987 for 1979, the peak of the generation, with the TH400 automatic and a 400 V8 at up to 185 hp on the list. Then 1980 shows 31,776 trucks, a drop of roughly 65 percent in one year that every table records and none explains. Two-wheel-drive Blazers were built alongside the 4x4s through 1982 per one source, and owners point out that they were K5s too: K5 was the model name, not a drive-system code.

Restyle, Diesel and the Army, 1981-1986

The 1981 refresh brought stacked quad headlamps and the chain-drive NP208 transfer case. The 305 V8 appears in the 1981 trucks with a 9.2:1 compression ratio that owners describe as prone to detonation; whether it was first offered in 1976 or 1981 is disputed. The 250 six remained standard through 1982, the year the 6.2-liter Detroit Diesel V8 arrived at 135 hp and 240 lb-ft. After a 1981 test bed, the Army took the Blazer as the M1009 CUCV, built from 1983 to 1987 with the 6.2 diesel.

V-Series and the Last Square Body, 1987-1991

For 1987 GM renamed the truck from C/K to R/V and introduced throttle-body injection, making the 350 standard at up to 210 hp and 300 lb-ft. The new GMT400 pickups took the C/K name, but the Blazer, Suburban and crew cabs stayed on the old platform. Small changes marked the final years: an NP241 transfer case after 1988, a fixed mast antenna for 1988, a full-bar grille for 1989, standard rear-wheel anti-lock brakes for 1990, and the 700R4 automatic renamed 4L60 for 1991. Owners note the fender badge still read K5 in 1988 and was gone after. Output fell to 7,332 for 1991 before the Blazer moved to the GMT400 platform, and the full-size two-door Blazer name was later replaced by the Tahoe.

The most specific known fault is the tailgate window: the electric motor on the K5 overheats and fails repeatedly, and the manual crank gears can wear prematurely. The 1981-on 305 V8, built with a 9.2:1 compression ratio and smaller combustion chambers, is described by owners as prone to detonation. Trucks that have sat suffer a cluster of age problems that one owner of a 1988 truck describes in detail: vacuum lines and connections failing, leaking front transmission seals, spongy brakes, a whining rear axle above 35 mph, a slipping transmission and a worn-out engine with a dead cylinder. The same owner reports underside rust from a coastal climate bad enough to require replacing almost the entire running gear, a ride he calls terrible, an original air conditioning system he calls poor, and fuel economy of 7 to 8 mpg. The forum and owner sources consulted do not publish failure rates, so these are reports of what goes wrong, not of how often. No NHTSA recall or complaint data was retrieved for this generation, which is a gap rather than evidence that none exists.

The first question is which of the three trucks it is. A 1973-1975 Blazer has the fully removable top; a 1976-1991 truck has the steel cab roof and a removable rear section held by 16 bolts, and a missing or cracked rear top is a separate expense. On early automatic trucks the transfer case is worth identifying, since the sources disagree on whether they left the factory with the full-time NP203 or the part-time NP205, and swaps over fifty years are common. Classic.com sorts results into original, modified and custom, and those categories carry different money: the same year can sell at $15,000 or at $130,000 depending on which one it is, so the condition and originality claims in a listing matter more than the model year. The badge is not a drive-system tell, because two-wheel-drive Blazers were also K5s; the running gear and paperwork are. For the 6.2 diesel trucks of 1982-1991 and the M1009 military trucks, the record of what has been done to the engine is most of the value. Underneath, owners who have restored these trucks describe frame-down work, with running gear and suspension parts needing replacement on trucks that sat outside, especially near the coast. A truck that has been parked for years tends to come back with vacuum-line leaks, idle problems and failed seals, and in states with emissions testing an idle that is too high can fail a smog check. The power tailgate window motor and the manual crank gears are both known wear items.

As of October 2026, classic.com showed 53 second-generation K5 Blazers for sale, but its market page displayed no average or benchmark figure, so none is quoted here. Individual results logged on classic.com through September 2026 show how wide the spread is. For 1985 trucks, a custom Silverado sold for $73,700 and a modified Silverado for $53,900 at Mecum in September 2026, while an original 1985 truck made $28,050 at Mecum in July 2026 and a project Silverado $11,350 on Hagerty's platform in August 2026. For 1973 trucks, a custom 2WD Blazer sold for $130,000 on Bring a Trailer in September 2026 and a custom K5 for $105,600 at Barrett-Jackson in January 2026, while original Cheyennes sold for $26,500 in November 2025 and $15,007 in October 2026. For 1980, original trucks brought $45,100 at Mecum and $39,600 at Barrett-Jackson in the first half of 2026 and $22,000 on Bring a Trailer in July 2026. Classic.com does not say on these pages whether each figure includes buyer's premium. The pattern, as of September 2026, is that the top of the market belongs to custom and modified builds, and an original truck in ordinary condition still trades in the $15,000 to $45,000 band. An undated Hagerty article describes the second-generation trucks as more affordable than the first, citing a 1987 truck at $28,600 and two others at $19,800.