ZF Autobox Oil & Filter Change

On current Range Rovers and Series II Discoverys, the autobox is sealed for life and needs no servicing. However, on older vehicles with the ZF fourspeed automatic gearbox, the oil and filter must be changed at regular service intervals. The recommended change is every 24,000 miles under normal driving conditions. Usually, then, it’s done as part of the normal 24,000-mile service.

The oil and filter change is one of those jobs that can be done at home lying on your back in the driveway, but the job is much easier with the vehicle on a post lift! The engine type also makes a big difference to how difficult the job is. The 200 Tdi and 300 Tdi are the easiest to work on, but with the V8s you have to remove the gearbox crossmember first. If the V8 has catalytic converters, then the front sections of the exhaust pipe need be removed to allow the gearbox sump to come off. We carried out this work on a 1995 Range Rover Classic 300 Tdi Automatic, so the gearbox crossmember did not have to come off first. However, one of the gearbox mountings did have to be removed to allow access to one of the sump clamp bolts.

The filter being replaced is part number RTC4653. The two O-rings that are also required do not come with the filter and need to be bought separately.

You can save yourself the time and trouble of hunting for all the elusive parts and a high quality fluid by buying a comprehensive and convenient service kit from our online store.

1. First job is to remove the dipstick and drain the gearbox sump. Not all 9 litres will drain out because the torque converter remains full of oil
2. Now remove the oil filler tube (also used for the dipstick) from the sump. This may be very tight, so take care not to bend it	3. The sump is held onto the bottom of the gearbox by six bolts with special retaining clamps, all different. Five can be removed easily .....	4. ..... but one is at the rear of the sump directly under the gearbox mounting bracket and is impossible to get at until the gearbox mounting is removed
5. A support is placed under the gearbox to take the weight once the mounting bracket is removed; with the bracket off, the remaining clamp bolt can be undone	6. With the last bolt removed, the sump can be dropped to expose the bottom of the gearbox, the oil pickup pipe and the filter that is to be replaced	7. Remove the oil pickup pipe, then unscrew three screw bolts (of two different lengths) which hold the filter in place to allow the filter to be removed
8. The replacement filter with new O-ring seals in place is shown before fitting; one O-ring is on the pickup pipe, the other on the gearbox feed side	9. The old filter case has been cut open here to show the fine wire mesh screen inside; this stops contaminants passing from sump into gearbox with the oil	10. Fit the new filter and refit the oil pickup pipe, then bolt the support bracket and spacer back (some models have a different bracket with no spacer)
11. Before refitting the sump to the gearbox, give the inside a thorough clean in order to remove old oil deposits and any swarf which may have accumulated	12. Fit the new gasket over the edge of the sump. It’s advisable to use a spray gasket adhesive, otherwise it won’t stay in place on the lip of the sump	13. Carefully refit the sump to the bottom of the gearbox. Ensure the gasket is correctly seated by running your finger round the edge when it’s on
14. Lay the sump on a flat surface and apply a little weight to ensure the gasket is on square and a good seal is made between gasket and sump
15. Carefully replace the bolt clamps. Tighten them by hand at first as they can easily be cross-threaded, then tighten to the torque setting	16. Once all clamps are refitted, the gearbox mounting can be replaced. This mounting also holds the kickdown cable, which may need to be adjusted as it's been disturbed	17. Don’t forget to refit the dipstick tube to the sump before you refill the gearbox with oil. Make sure you use the correct type DIII ATF
18. Refill the gearbox with the same amount of oil as you drained out. Check level, then run engine and recheck. Never over-fill, as this will damage the gearbox!	One thing to note is that you will only be able to drain around 4 - 5 Litres when changing the Filter screen (4-5 Litres remains in the Torque Converter). Hence we recommend you change the filter, refill with fluid and drive the vehicle for 500 miles or so. Following this, drain the sump once again but ONLY using the drain plug, don’t remove the sump. Then refill with another 4-5 Litres of new ATF and you will have renewed 75% of the fluid, which is as much as reasonably possible during servicing. You won’t need to renew the filter and fluid again for another 24,000 miles.