Automatic Gearbox Easy Change Kit with Metal Sump, Filter, Liqui Moly ATF and Wiring Sleeve for Discovery 4

The ZF 6HP26 6-speed automatic gearbox fitted to early Land Rover Discovery 4 models was originally described as “sealed for life”. In real-world use however, transmission fluid gradually degrades due to heat cycles and mileage.

As the fluid deteriorates it can lead to reduced lubrication and declining gearbox performance. Common symptoms include torque converter judder, slipping between gears, delayed engagement and harsh gear changes. Regular servicing helps maintain smooth gearbox operation and prolong the life of the transmission.

This comprehensive gearbox service kit includes a metal easy-change sump conversion, high quality Liqui Moly Top Tec 1800 automatic transmission fluid and a replacement gearbox wiring sleeve. The wiring sleeve is a known leak point on ZF 6HP26 gearboxes, so replacing it during servicing helps prevent fluid leaks and electrical connection problems.

The factory transmission sump incorporates the filter, meaning replacement normally requires lifting the engine and removing surrounding components. This easy-change conversion replaces the original plastic sump with a durable metal pan and a separate replaceable filter, making future gearbox servicing significantly easier.

Common symptoms of degraded gearbox fluid

• Torque converter shudder during light acceleration
• Harsh or delayed gear changes
• Gear slipping or hesitation
• Noisy transmission operation
• Poor shift quality when hot or cold

If your Discovery 4 is experiencing any of these symptoms, servicing the gearbox fluid and filter can often restore smoother gearbox operation.

Kit contents

• Easy-change metal transmission sump pan
• Separate replaceable gearbox filter
• Gearbox sump gasket
• Complete set of replacement sump bolts
• 7 litres Liqui Moly Top Tec 1800 automatic transmission fluid
• ZF gearbox wiring sleeve

The 7 litres of ATF included allows a double drain and refill process, helping replace a greater percentage of the old fluid during servicing.

Easy-change sump conversion process

1. Drain the transmission fluid and remove the sump bolts.
2. Carefully cut the plastic filter neck on the original sump.
3. Remove the original plastic sump pan.
4. Install the new separate filter.
5. Replace the gearbox wiring sleeve.
6. Fit the metal sump pan using the supplied gasket and bolts.
7. Refill the transmission following the correct ZF gearbox filling procedure.

Vehicle compatibility

Discovery 4 (L319) 2009-2012
Models fitted with the ZF 6HP26 6-speed automatic gearbox

This kit is not suitable for Discovery 4 models fitted with the later 8-speed automatic transmission.