Symptoms
Coolant odour with no visible leak, slow coolant loss, a gravelly rattle from the supercharger at idle.
The fix, step by step
- On the SC V6 the front 'Y' crossover sits under the supercharger.
- Drain the coolant, remove the charge-air cooler and supercharger (it sits on two dowel pins; rock it from the snout and pry gently, minding the knock sensors underneath), then replace the front crossover (redesigned LR090630 and LR092992), the rear heater manifold, the water pump and the thermostat.
- One owner found his front pipe eaten away above the O-rings at 50,100 miles.
- Replace the supercharger coupler isolator while the blower is off.
- Refill and bleed the system.
Tools & part numbers
- Metric sockets and Torx, pry bar, new gaskets and O-rings
- LR090630, LR092992 front crossover, LR109401 rear manifold, LR097165 pump, LR095895 thermostat kit (one owner's DIY list)
Where to buy the parts
Hunting a used or discontinued part? Search eBay Motors for Land Rover LR4 / Discovery 4 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.