Change gearbox oil?

Following an oil change a few members noted significant amounts of water in the gearbox which found its way into the oil via worn seals in the gearbox tower.
Others have noted very low oil levels which is a risk on s/h cars where the oil slick has been cleaned up without checking the source.
Any oil does degrade over time due to oxidation and moisture caused by internal condensation

All good reasons why changing the oil after a few years is good preventative maintenance

Regarding problems after a gearbox oil change, the only reasons could be
(1) use of the wrong oil ( the genuine Audi oil is significantly 'thinner' than the majority of regular 75w90 oils specified on many other car models and can result in a stiff gearchange particularly in cold weather.
(2) difficulty removing / replacing the fill and drain plugs resulting in damaged threads and possible oil leaks

Cheers Spike
 
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Very good point on water ingress - this is also contributed to by the bonnet drain cup which over time is often displaced, broken or missing entirely - the bonnet drain on that side is located directly above the shift tower.

Another cause of issues following an oil change is damage caused by overfilling - easily done as the car must be level to get the correct fill amount. If, as most home mechanics will do, the car is merely supported on stands under the front axels, there will be far too much oil inside as the box will be tilted backward by a few degrees. Hardly likely to cause hydraulicking, but it'll put pressure on seals and cause leaks in the short term.
 
Following an oil change a few members noted significant amounts of water in the gearbox which found its way into the oil via worn seals in the gearbox tower.
Others have noted very low oil levels which is a risk on s/h cars where the oil slick has been cleaned up without checking the source.
Any oil does degrade over time due to oxidation and moisture caused by internal condensation

All good reasons why changing the oil after a few years is good preventative maintenance

Regarding problems after a gearbox oil change, the only reasons could be
(1) use of the wrong oil ( the genuine Audi oil is significantly 'thinner' than the majority of regular 75w90 oils specified on many other car models and can result in a stiff gearchange particularly in cold weather.
(2) difficulty removing / replacing the fill and drain plugs resulting in damaged threads and possible oil leaks

Cheers Spike
I’ve mentioned it before, but the Redline MT-LV transmission oil is excellent, it’s lower viscosity than the standard Audi oil but according to Opie Oils, it’s wear protection properties are as good, if not better
 
Another cause of issues following an oil change is damage caused by overfilling - easily done as the car must be level to get the correct fill amount. If, as most home mechanics will do, the car is merely supported on stands under the front axels, there will be far too much oil inside as the box will be tilted backward by a few degrees. Hardly likely to cause hydraulicking, but it'll put pressure on seals and cause leaks in the short term.

Is it not the other way round ( at least for petrols)? The fill and drain plugs are at the back, so when the front of the car is raised the gearbox holds less oil, not more. I did this at the weekend as it happens, and after filling it with the car level on the ground I quickly realised my lack of planning as soon as I started to raise the front again. Ended up having to hand-screw the fill plug in with the car on the ground (possible, but needless to say not recommended!). This was at least enough to stop leaks until I'd jacked it up and tightened it properly.
 
Is it not the other way round ( at least for petrols)? The fill and drain plugs are at the back, so when the front of the car is raised the gearbox holds less oil, not more. I did this at the weekend as it happens, and after filling it with the car level on the ground I quickly realised my lack of planning as soon as I started to raise the front again. Ended up having to hand-screw the fill plug in with the car on the ground (possible, but needless to say not recommended!). This was at least enough to stop leaks until I'd jacked it up and tightened it properly.
No, diesels have the filling plug on the front of the box casing, next to the condenser/radiator panel.
 
Does anyone have a photo of the drain and fill plugs on 1.4 AUA engine (FDM transmission code).
And possibly also a part nr. for the plugs.
 
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