Common problems · 1969–72
1st Gen K5 Blazer & Jimmy problems: 8 things to check
The problems owners and specialists flag most on the Chevrolet K5 Blazer (1st generation), the repairs they end up doing and what those cost, plus the years and recalls to watch. Sourced, not scraped.
1st Gen K5 Blazer & Jimmy problems to check before you buy
- Rust first, drivetrain secondVelocity Restorations lists the floorboards, wheel wells, inner fenders and door bottoms as the usual rust spots. The Drive adds the top of the windshield frame. Fresh paint can hide all of it, so bring a magnet and look underneath.
- Inspect the frame at the steering boxOffroad Design says straight-axle GM trucks are notorious for frame cracks where the steering box mounts, especially with lifts, big tires and off-road use. Look for cracks and old weld repairs on the driver's-side rail ahead of the front axle.
- Is the top there, and does it fit?Many first-gen trucks have lost their hardtop or soft top. The Drive notes that the fiberglass top's textured finish is hard to match in repairs. Check the top's mounting edge, the liftgate and the seals, because a leaky or missing top is expensive to sort out.
- Work out what has been swappedRecent BaT results include LS, Vortec, 383, 454 and 6.2 L swaps alongside original trucks. Velocity advises caution unless swap work is documented and done by a qualified builder. Decide whether you're paying for originality or for the build.
- Read the SPID decalFactory equipment and paint are listed on the Service Parts Identification decal inside the glovebox, per a 1969 BaT listing. Use it to check a claimed CST, Positraction or V8 truck.
- Expect a loose chassisThe Drive warns that the chassis is flexible and the steering has play, and that a big power upgrade can make the handling worse. Budget for steering-box, tie-rod and bushing work, and drive it before you agree a price.
- Check which transfer case and hubs it hasManual trucks may have the Dana 20 or the NP205. Automatic trucks have the NP205. Offroad Design notes the NP205's tag sits above the front output and that the case is one piece of cast iron. Make sure the hubs lock and unlock.
- Mind the brakes on 1969–70 trucksFront discs became standard for 1971. Earlier trucks have four-wheel drums unless they've been converted, so ask what has been changed and how well it was done.
The repairs 1st Gen K5 Blazer & Jimmy owners end up doing
| REPAIR | SYMPTOMS | DIFFICULTY | TIME | COST |
|---|---|---|---|---|
| Brace the steering box mount before the frame cracks | Steering that wanders or clunks, the steering box moving on the frame when someone saws at the wheel, or visible cracks around the box mounting bolts on a lifted or big-tire truck. | 2 / 5 | ≈ 2–3 hours | Parts plus a drill and basic hand tools |
| Reseal the hardtop, liftgate and doors | Water on the floors after rain or a car wash, wind noise at speed, or rust starting under old seals. | 2 / 5 | ≈ A weekend | Seals plus adhesive |
| Cut out and replace rotten floors, rockers and wheelhouses | Soft or perforated floor pans, bubbling rockers and door bottoms, or rotten rear inner wheelhouses. These are the areas Velocity Restorations and The Drive flag. | 4 / 5 | ≈ Several weekends | Panels are cheap; welding time isn't |
| Repack front wheel bearings and replace spindle seals | Play at the top and bottom of the tire, a growl that changes as you turn, or grease and water inside the hub after deep water. | 3 / 5 | ≈ Half a day | Bearing kits plus grease |
| Replace worn locking hubs | Hubs that won't engage, pop out in four-wheel drive, or let the front driveshaft spin in two-wheel drive. | 2 / 5 | ≈ 1–2 hours | A pair of hubs |
| Rebush the leaf springs and shackles | Clunks over bumps, vague steering, a truck that leans or sits low on one side, or cracked rubber at the spring eyes and shackles. | 3 / 5 | ≈ A day | Bushing kit plus new hardware |
| Service the brakes (drums to 1970, front discs from 1971) | A pull to one side, a low or spongy pedal, or seeping wheel cylinders. Also any truck that has sat for years. | 2 / 5 | ≈ Half a day | Parts plus brake fluid |
Each repair links to a step-by-step guide with tools, part numbers and where to buy the parts.
Take the printable 1st Gen K5 Blazer & Jimmy inspection checklist: every check on this page plus the model-specific ones, on one sheet. Get the checklist →
Sourced from owners, specialists and factory documents; full sources are on the 1st Gen K5 Blazer & Jimmy guide. Verify torque figures and procedures against the factory service manual (disclaimer).