Change gearbox oil?

Skipton01

Admin Team
Bear in mind that there's no such thing as a mechanical 'sealed for life' gearbox - anything that spins in a bath of oil will degrade that oil over time with heat cycles and shear forces on the molecules. No oil ever made will perform with the same efficiency after 100,000 miles as it did when new, it's a simple and unquestionable fact.

So, with this in mind, all our A2 gearboxes will need an oil refresh at some point to keep them in good condition is the answer to your initial question. Whether a mechanic deems it necessary is irrelevant, they could simply have been talking themselves out of a job they didn't want to do for whatever reason. Their experience is of paramount importance in their mind, but hardly exhaustive when it comes to the question of A2 gearboxes, which have been stripped and built, modified and tweeked by many members here, myself included.

Rather than him just do it and cross his fingers, I'd urge you not to have the work done by them, because the chances are, in their experience, something will subsequently go wrong. This gives them a get out clause of "I told you so". I'd recommend you have the work done by someone who knows what the procedure is, what type and amount of oil to use and how to ensure that you don't have issues.
 
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Ami

A2OC Donor
Hi,

I can supply the gear oil mentioned in this thread for £20.00 for 2 Litres inc UK postage if any members are interested.

Thanks
Hi:
Is that oil compatible for tdi 75 gearbox, £20 posted sounds good to me.
Thanks,
Ami
 

Crgwal

Member
I changed my gearbox oil at 120k miles. I have been told it should be good for 500k miles.

I noticed zero gain after changing my gearbox oil.

Sorry havnt read all posts but maybe above will help.
 

PlasticMac

Member
I changed the oil in my Mk1 TT at 70,000mls. The old oil looked past it's best, for sure. The changes were much as before. No regrets. As others have said, nothing last for ever, including oil.
£20 every 15 years or so? Hardly a major expense is it!
Mac.
 

Skipton01

Admin Team
Think of it another way:

You know if you're ever lucky enough to buy a brand new car, they always tell you to run it in and then there's a very short service interval to the first oil change, which ensures that any microscopic metal particles are cleared out (the metal will come from the moving engine parts as they bed into each other).

Well, the gearbox works the same way - cogs interlocking with each other, synchros sliding over each other etc. Why doesn't the gearbox oil get changed at the same time as the first oil change? There'll be swarf in there for sure, just as there is in the main sump. There's not even a filter or strainer in the gearbox either, so if anything, I'd say it's more urgent to change the gear oil if it's never been done.

There may not be any 'gain' felt after a change, but there'll not be any detriment either, just the opposite - contaminants are removed and the lubrication of the metal parts is renewed. I just don't see that there's a debate over this, or are people actually buying into the idea of something mechanical being sealed for life? Ever heard of planned obsolescence? I wonder what the definition of 'life' is for an 02J gearbox?
 

Vic

Member
More than a year since the gearbox oil change for my TDI 75 and everything is fine. Used original VAG gearbox oil.

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Ami

A2OC Donor
I am hoping to get mine next week, when you change the oil, pls do a few lines on how you got on changing it & any pit falls etc :)
Cheers,
 

thejohn

Member
Hi Ami, when I changed my gearbox oil the only issue was filling the box. I ended up with a piece of garden hose on the end of a funnel running down the rear of the engine into the fill hole. I have also seen a gearbox filled with a large syringe with the appropriate quantity of oil through the reverse light switch from below at the front of the engine. Other than that I encountered no issues. Unlike headlight connectors :(.
John
 

Ami

A2OC Donor
Morning John:
Perfect, I have a large Syringe, I will have a go when I get the oil. :)

What was the problem with headlight connectors, I normally spray some Wd 40 on the connector & it comes off much easier.
Ami
 

Hans

Member
The gear box in my car gets new oil every second year. After a bit more than 310 000 miles it still shifts fine, I have driven new cars that shifts far worse. I use a fully synthetic 75W-90 transmission oil that does not damage "yellow metal". It is a bit of a hassle to get a long hose into the opening, and one must protect the hose end so it doesn't collect any dirt on the way down and in. Making sure that everything is clean and that no debris enters the gearbox during the oil change is of course very important. Also worth having in mind is that if the car is at unfavorable angle, it might stop you from getting the right volume filled.
I think replacing all oils and fluids at regular intervals is key to high mileage without a lot of repairs.
 
Utter rubbish. If that were the case, why put drain and fill holes in the casing?

I’d say it’s just that they did t know the procedure that’s all.
"why put drain and fill holes in the casing?"

Fill: To fill with oil at manufacture.
To fill with oil at replacement.
To fill with oil after repair.

Drain: To drain oil before repair.
To drain oil before disposal.
 

Skipton01

Admin Team
"why put drain and fill holes in the casing?"

Fill: To fill with oil at manufacture.
To fill with oil at replacement.
To fill with oil after repair.

Drain: To drain oil before repair.
To drain oil before disposal.
Straws being clutched at?

If this were the case, then the filling at manufacture would be via an existing point of entry, such as the shift tower, same goes for replacement or after repair. Draining before repair or disposal? No commercial workshop these days uses drain plugs for engine oil - they all use suction to cut down on service time. Draining at time of disposal would be done either by removing the end cap of the box, or drilling into the casing. Draining before repair would be done via suction through the shift tower.

I maintain, as does the consensus here, that A2 gearboxes all benefit from a change of oil and there's a wealth of first hand evidence to back this up across not just this forum, but many other Audi owners clubs. When pressed, dealers will often have a fall back position of 'life' means 100k miles. Pretty much every A2 ever made will be close to this 'life' limit, many are well past it.
 
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