Bolt, Rear Suspension Crossmember 12x105mm (Genuine) EVO4-9

Bolt – Rear Suspension Crossmember 12x105mm (Genuine) EVO4–9 (MB809344)
Genuine Mitsubishi rear suspension crossmember bolt. Designed for a precise fit and factory-grade strength on EVO4-9 models.
Commonly seized due to rust in the body shell — ideal for replacement during rear subframe or suspension service.

⚙️ Steps & Tips : Removing Seized/Rusted Bolt

1. Pre-soak the bolt

   • Spray penetrating oil generously around the bolt head and threads (if accessible).

   • Let it sit for several hours or overnight. Reapply multiple times.

2. Clean exposed threads

   • Use a wire brush to remove surface rust. This helps the penetrant and tools grip better.

3. Loosen slightly, then tighten

   • Try moving the bolt back and forth gently instead of forcing it all one way — this can help the rust break free gradually.

4. Apply heat

   • Use a torch to heat the metal surrounding the bolt (not the bolt itself).

   • The expansion of the surrounding metal can break the rust bond.

   • Let it cool slightly, then apply more penetrant — it will wick in as the metal contracts.

5. Use impact over brute force

   • A quality impact gun delivers shock that helps break corrosion bonds more effectively than steady pressure.

6. If the bolt spins but won’t come out

   • It may be seized inside a rusted inner sleeve or captive nut inside the chassis.

   • Continue alternating heat, penetrant, and impact.

   • If the captive nut breaks free and spins inside the chassis, access may need to be made (cut or open the floor to grip it — common on Evos).

7. Last resort – cut or drill

   • If the bolt snaps, cut through the bolt between the subframe and body using a reciprocating saw or cut-off wheel.

   • Drill out the remaining bolt and clean the hole before re-tapping or replacing the nut.