Videos

Early 90s G350 Turbo Diesel Recovery and OM606 Upgrade by Alliance Auto Care

When a client’s early 90s G350 Turbo Diesel failed miles from home, Alliance Auto Care stepped in. From engine diagnostics to a full OM606 upgrade, turbo improvements, and suspension enhancements, this G-Wagen was rescued and built for long-term reliability.

Rescuing a Broken Classic

What do you do when you pick up your G-Wagen and it fails just miles down the road? That’s exactly what happened to this early 90s Mercedes-Benz G350 Turbo Diesel. The previous shop couldn’t solve the problem, so the owner called Alliance Auto Care. Within hours, the truck was transported safely to our shop, and the full diagnostic revealed a seized camshaft — a catastrophic failure that rendered the motor inoperable.

Turning Disaster into Opportunity

Instead of simply repairing the broken 603 turbocharged motor, we worked with the client to upgrade to a low-mileage OM606. The upgrade included a 6-millimeter mechanical fuel pump and an enhanced turbocharger, balancing increased reliability and drivability without going for extreme power.

The process also involved suspension and chassis updates, ensuring the G350 could stop, steer, and handle perfectly, even with the enhanced engine performance.

Step-by-Step Engine Upgrade

The OM606 crate motor arrived from Canada, complete with accessories such as alternator, water pump, power steering pump, AC compressor, and glow plug relay controller. Every component was inspected, resealed, and tested for optimal performance.

The combination of upgraded turbo internals and a carefully spec’d fuel pump ensures smooth operation, minimal smoke, and daily-drivable reliability — perfect for owners who want dependable performance without compromising comfort.

Suspension and Chassis Improvements

To match the engine upgrade, the truck received Fox 2.0 shocks, factory ride-height springs, and new bushings on control arms and tie rods. This ensures that the G350’s enhanced horsepower translates into precise steering, braking, and handling on the road.

Choosing the Right Shop

Selecting the correct shop is critical when working on classic or rare G-Wagens. Key considerations:

  • Experience with Mercedes-Benz, especially early diesels like the 603 and 606.

  • Familiarity with four-wheel-drive systems; experience with early Land Rovers often helps.

  • Knowledge of German brands including Porsche, Audi, VW, BMW, for electronics and hard-to-source parts.

  • Ability to fabricate or source obsolete components like oil lines or wiring harnesses.

If in doubt, our team collaborates with other shops across the country to ensure your G-Wagen gets correct parts and upgrades.

End-to-End Service

Once your vehicle arrives, we handle:

  1. Transportation logistics nationwide.

  2. Full top-to-bottom inspection.

  3. Clear communication of all options — repair, upgrade, or enhancement.

  4. Execution of engine rebuild or upgrade, turbo tuning, suspension improvements, and chassis work.

Reliability and Longevity First

This G350 project highlights the importance of strategic upgrades over quick fixes. By focusing on reliability, drivability, and proper engineering, we ensure this classic diesel G-Wagen can perform for many years to come.

📞What It Takes

Expect a 4–8 week timeline, depending on parts availability and scope. A full job like this can range from $10,000 for partial work to $30,000+ for full disassembly, rust remediation, paint, and reassembly. But in Joe’s words: “The money you put into it now pays dividends down the road.”

Interested in restoring your G-Wagen?

Contact Joe Gocher at Alliance Auto Care in Loveland, Colorado.

Tag Post :
Alliance Auto Care,Early 90s G-Wagen,Engine Swap,G350 Turbo Diesel,Mercedes Diesel,OM606 Upgrade,Suspension Upgrade