How to change Td6 automatic gearbox oil | |
As I own a Td6 with a GM 5L40-E automatic gearbox and the ATF change procedure isn’t really explained anywhere (it's actually quite controversial), I thought I should write this down. As my car was approaching 125000km and after reading hundreds of posts both on BMW and LR forums, I decided it’s better to change the “filled for life” gearbox oil. I also was concerned with the shudders my car started to have while reversing, or the vibrations that were felt if stationary when in D. The documentation in RAVE does not deal with filter change, and the gearbox filter isn’t even listed in Microcat! The special Texaco oil isn’t even available in my country! So after identifying the GM5L40-E as the BMW A5S360R gearbox and the Texaco ETL 7045E oil as the BMW p/n 83 22 0 026 922, I tried to find them as cheap as possible. The oil is available only at the BMW dealer for 11EUR/liter, but the filter (p/n 24117557070) costs over 90 EUR there, so I found a Bilstein filter kit for 40EUR. I purchased 9 liters, in the end I used less than 7.
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Right, with the help of a mechanic friend (and who owns a ramp), I started the draining of the gearbox oil.
The engine was warm, so we loosened the fill plug that is situated on the left side( facing forward) towards the front of the gearbox, and then we removed the drain plug that is on the bottom in the front (my car is LHD). We got more than 6 liters out, and we started to remove the 20 bolts. The pan was removed easily and we started cleaning it and the magnet too.
The oil was dirty, not totally black though and there were some particles on the magnet but nothing to be worried about.
The surprise came when we noticed that the bottom part of the filter was different from the one I bought!
My mechanic friend decided that LR probably enhanced the design to avoid any chance of it getting loose from very rough off-road handling, but as the filter was very hard to remove from the pump in the first place and it’s supported anyway to the rear by the shape of the pan, we decided that there is no risk in using the new filter.
While removing the old filter we noticed that there are 2 o-rings on the tube pointing upwards and one of them remained stuck in the hole. We got it out with a hook made from thick wire. After cleaning the gasket location thoroughly, we fitted the new filter; then the clean pan with the magnet in place and the gasket were tightened with the new bolts provided in the kit. We refitted the drain plug and started putting back fresh oil. After 4 liters it started pouring from the fill hole, so we tightened the fill plug a little and started the engine. While pressing the brake pedal and with the engine running, I went through all the gears a dozen times.
After stopping the engine we refilled with more oil until it started overflowing. We tightened the plug a little again and started the engine. With the foot on the brake I shifted to N and my friend unscrewed the fill plug and added some more oil. We stopped the engine, tightened the plug and I drove around the block. When back and with the engine off, we opened the fill plug and about 250g of oil poured from it.
[amendment : ............. it is now known and recommended that gearbox oil should only be added with engine running]
Amendments (with thanks to RRPhil):
- If possible, use a genuine Filtran replacement filter
- Replace fluid with fresh fluid until it starts dripping out of the fill hole
Both the ZF & GM transmission fluid levels need to be set with the engine (and therefore the transmission oil pump) running so that the torque converter, oil cooler and its pipes are all full of fluid and not draining back down into the sump.
- Start engine, hold foot brake down and cycle through each gear position holding for 5s (from park to drive & back) to ensure that the valve block galleries are full. Ensure that you finish in Park with the handbrake on.
- WITH THE ENGINE STILL RUNNING wait for the transmission fluid to reach 43C and top up as necessary
- Refit fill plug, tighten and turn ignition off
- Reset the transmission/ gearbox controller (with ignition off, push accelerator pedal to the floor; ignition to position 2; continue holding accelerator pedal to floor for 60s; ignition off; pedal release)
At this point we tightened the plug for good and off I went. The whole deal took 2 hours, it’s not difficult and if done properly it’s not dangerous at all. After 10km I can say that the shudders and hesitations are gone, the shifts are smoother and the noise seems to be lower too... It would be great if I could repeat this procedure after a few hundreds km, this way more of the original oil would be swapped.
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