1973–91 K5 Blazer, second generation chassis stiffening
2 kits to stiffen the frame, from frame rails and connectors to braces and roll bars.
- How it's built
- Full ladder frame (open C-channel rails; shares the C/K pickup chassis)
- Weak spots
- The frame cracks at the steering box mount, and the front leafs ride harshly. Stock steering geometry is vague and binds when the truck is lifted or the axle articulates.
Stiffening kits
| Area | Kit | What it is | Price |
|---|---|---|---|
| Frame stiffening | Offroad Design Weld On Frame Repair Kit for '73-91 GM Trucks | Weld-on plates to repair a cracked box-mount area | $79 Listed on OD category page Source |
| Frame stiffening | Offroad Design Bolt-In Steering Box Frame Brace, 1973-1991 4WD GM Full-Size | Cross-frame brace that stops box-mount cracking | $140 Listed on OD category page; 67-72 version also $140 Source |
Prices are from the linked seller pages and change often. Confirm fitment for your exact year and body style before ordering; many weld-in parts need professional installation. Some links earn us a commission.
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