Changing W58 gearbox oil

[stevie_b]

I'd like to change the gearbox oil in my car for the first time. I've had it done by other people before. Never having changed any gearbox oil in my life, is the procedure to change the W58 oil similar to changing the V160/161 oil described here? -> http://www.mkivsupra.net/vbb/showthread.php?35935-FAQ-The-manual-gearbox

 

e.g. does the car need to be level when doing it? Does the engine need to be on when draining the oil, or only when refilling it?

 

I've searched for a guide on changing the W58 oil but couldn't find one.

[Chris Wilson]

Engine off at all times. ALWAYS check you can remove the filler / level plug BEFORE removing the drain plug. You will need some means of injecting the new oil into the box.

 

Car needs to be pretty level.

[zaheer0027]

I did mine myself. It's very simple. I made a write up but it's on my work computer. Briefly you do the ffg:

 

1. Car off. Preferably have car on axle stands on all 4 wheels. Makes life a little easier as you have to get under at a certain point.

 

2. Get under the car and you will see drain plug for gearbox at the bottom. Remove and let oil drain out

 

3.on the lhs almost middle of the box you will see a plug. Open. This is the fill plug.

 

4.now go inside the car remove the gear shift plastic console. Remove the 4 screws holding the gear surround. You should be able to see below your car through the gap now. Feed a pipe or hose down through the gap. Now go back under the car and feed the pipe into the fill plug hole.

 

5.now go back into the car and fill your oil through the pipe. The oil is full when it starts to over flow through the fill hole.

 

And that's it. Like I said I have a write up with pics and stuff if you still need it let me know.

[stevie_b]

Thanks for the tips. Zaheer, could I see the guide you've written please? Pictures etc make learning the job much easier.

[zaheer0027]

Ok will upload tomorrow at work

[zaheer0027]

Here you go

 

https://www.dropbox.com/s/moigdzqbqqrh0i3/W58%20FLUID%20CHANGE.docx?dl=0

[stevie_b]

Thank you very much. This could be useful as the basis for a sticky how-to thread about it.

[stevie_b]

I've got a question about the procedure: am I correct in thinking that the oil level should be checked when it's at normal operating temperature? (I presume normal=hot, but I'm not sure because there's no combustion going on around there.)

 

If it needs to be hot when checking the oil level, how do you do this? The new oil going in will be at room temperature. If you fill it with oil up to the filler hole then close the filler nut, surely it'll be overfilled when the oil gets hot and expands. So do you need to fill it with room-temp oil until it's full, then start the car and let any excess dribble out as it expands, then when the dribbling stops, that's the correct level?

[zaheer0027]

I am not technically minded on these matters but as far as I know even with engine oil you have to fill or check the oil before running the engine to get the correct level measurement.

[Chris Wilson]

Stone cold is fine, so is hot, they hold sod all oil, temperature makes little difference to the level, don't worry about that. Temp applies to auto boxes with circa a gallon + of oil in them.

[stevie_b]

Do either the fill plug or drain plug have washers which should be replaced?

[Chris Wilson]

No, they are taper threads, you can wind a bit of PTFE tape around them if they are weeping, but DO NOT overtighten them! As they are a taper thread tightening them imparts a HUGE expanding force on the gearbox casting. I have seen many gearboxes scrapped due to overtightening and splitting the gearbox casing. They don't need to be mega tight, just nip them up. Not sure if there's a torque figure for them, i just do them by feel. A normal 17mm combination spanner, or whatever size they are, is plenty long enough to get them more than tight enough. I see loads where you need a breaker bar to undo them! That's *FAR* too tight!!