Symptoms
Power drops after heat soak, especially in traffic or at crawling speed; intake temperatures climb.
The fix, step by step
- Replace the electric intercooler circulation pump with the updated Bosch unit, then bleed the low-temperature circuit.
- Victory Road Performance recommends replacing it as routine maintenance because the original pump failed often.
- GwagenParts sells a higher-flow bolt-in pump for 2006–2010 G 55s.
Tools & part numbers
- Updated Bosch intercooler pump or upgrade pump
- coolant
- hose clamps
- bleeding funnel
Where to buy the parts
Bosch intercooler pump kit with coolant (G 55 2005–11)FCP Euro ↗Amazon ↗
Intercooler pump upgrade (Johnson CM-30)GwagenParts.com ↗Amazon ↗
VRP M113K split cooling kitFCP Euro ↗Amazon ↗
Hunting a used or discontinued part? Search eBay Motors for Mercedes-Benz G 55 AMG parts →
Rated for a competent home mechanic with a decent tool kit. Confirm torque figures, fluids and procedures against the factory service manual for your VIN, support the truck on stands rather than a jack, and work at your own risk (disclaimer). Some parts links are affiliate links, which pay us a small commission at no cost to you.