Replacing diff oil & gearbox/transmission oil tomorrow

The Doctor

The Doctor

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Well I've at last found the time to get this done. My wife's taking the kids out all morning so I should get some peace & quiet for a change, which I will spend hiding under the car. Hopefully all will go OK... No problems with the car as such, just want to refresh the oil afer 8 years and 85k miles. Will report back on progress tomorrow.
 
Look forward to hearing this, i'm doing mine and also the Haldex at the weekend.

Where did you get your oils from as a matter of interest?
 
Oil was from Opie oils. I'll post up what I used tomorrow. Re pics, I'm working from these previous threads so not planning to take any more:

http://www.audi-sport.net/vb/a3-s3-...-speed-4wd-gearbox-front-diff-oil-change.html

http://www.audi-sport.net/vb/a3-s3-forum-8l-chassis/107092-help-rear-diff-oil-quantity.html

Haldex is easy so long as you have the filter removal tool. Did mine & filter last year. Re-filling is a PITA because you basically have to fill through the drain hole so it's tricky to get the plug back in without losing too much fluid.
 
Glad my threads are coming in handy ;) Noticeable difference in cold weather after changing the gearbox oil.

I find filling the haldex using the fill level hole is much easier, tube of oil fits nicely along next to the exhaust.
 
Yeah -thanks pj123, great thread!

Well, rear diff oil was changed this morning. Only challenge was getting the 17mm hex socket into position to get the fill hole plug out. It's really cramped in there, but after a bit of gentle "persuasion" and swearing it went in OK. As expected, the magnetic drain plug had captured some metal filings over the years but I cleaned these off before re-filling the diff. The oil that came out was blackened but OK. Re-filled with 1L of Fuchs Titan Sintopoid 75W85 gear oil bought from Opie oils, using a Clarke oil suction pump. Took about an hour to do all-in.

The problem came with the front gearbox - both the 14mm drain and fill hole plugs are security-hexes on my 2003 model (ie a 14mm hex bit with a protrusion in the centre) which means I couldn't get them out with my standard 14mm hex socket. Does anyone know where I can get a 14mm hex-socket with a dimple/hole in the centre? It's really annoying because the transmission drain plug and the rear diff plugs are just standard hexes, so why they've used security-hexes on the gearbox I don't know! Thankfully I was only replacing the oil as a service, not to correct any problem with gear-changing, so at least the car is still useable.

Anyway, I decided to do the N249 bypass instead, which I've been meaning to do for some time.
 
I'm going to be doing this (front and rear oils) when I fit my peloquin rear diff. Hopefully the guy's garage I'll be using (ex VW Racing) has all the bits to do it!
 
OK, well I replaced the gearbox & transmission oil this morning. Again, easy once you have one of these:

Draper 63476 1/2-Inch Drive Volkswagon or Audi Drain Plug Key: Amazon.co.uk: DIY & Tools

The photos in the link in my earlier post refer to a 14mm hex for the gearbox drain & fill plugs, but mine has a 14mm spline fitting.

Anyway, drained old oil out from gearbox and transmission (10mm hex plug) and collected about 2.5L in total. Lots of metal filings clinging to the transmission plug as expected, so cleaned these off. Re-filled with Motyl 75w90 Gear Oil using an oil suction pump until level with the fill hole, then drove round the block gently to fill the transmission and topped up again. Took about 2.9L all together. Took me about 90mins all in.

Satisfied that it's got fresh oil in the whole drivetrain now (did Haldex about 6k miles ago).
 
I have a question boys !
I recently had my oil changed in my gear box, but my mechanic (a friend of mine) only drained the oil from the gear box & not from the transmission box & filled it back up to the level plug.... with out taking for a spin & topping it back up again.

does that mean there aint enough oil in my gear/transmission box

as im a bit worried after read this thread:readit:
 
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So long as he topped it up until it just started to dribble out of the fill-hole then it has the right quantity of oil in it. However you will have about 2.5l of new oil mixed in with about 0.4l of old oil that would have been left in the transmission. Depends on your view on that. For someone with OCD like me, I wouldn't be happy because you've still got a fair amount of old oil in there and the magnetic plug on the transmission drain will still have all of the metal filings attached to it that accumulate in the gearbox/transmission over time.

If you only drain the gearbox, there is some oil left in the transmission (0.4l), If you don't drain the transmission you don't need to drive it to re-fill the transmission from the gearbox. Problem is you don't remove that old oil either.

Make sense?
 
Did you notice any difference at all after you changed both sets of oil?
Does anyone know if the gearbox oil and diff oil be the same for a 4WD diesel model?

Thanks
 
Have a look at the Opie Oils website - they have a search facility to determine the right oil by car.

I didn't have any problems with the car before changing the oil and it's still fine now so I have not noticed any difference. I did it as a routine service/preventive measure rather than to correct a problem.
 
Just jumping on an old thread here. I changed my front and rear diff oils as well as draining the front transfer box oil. Topped it up to the fill plug level, drove it then re-topped up as required.

I've now seen the procedure in a VAG A3 Manual and it doesn't stipulate to drain the transfer box oil only the transmission/gearbox oil.

I have a high pitched whine so my fear is that the transfer box doesn't fill form the trainsmission/gearbox oil and that it is running dry. Can anyone shed any light on this please as I'm very concerned.
 
audi upgrades
Very true. I'm just happy that its correct. I've found your old post pn here showing your removed gearbox with the transfer box pictured showing how it transfers oil as well.

Is there anything you haven't carried out on your car? I appreciate the help as always Tuffty.
 
Good thing i've noticed a thread like this as i may need some help, saves me making a new thread lol.

Planning on doing a gearbox/transferbox oil change along with the rear haldex but my question is wether anyone know the part numbers or know any specific diagrams for the transferbox seals? I want to remove my transfer box from the gearbox anyway for the other job i'm doing and it'd be nice to have it all done right, also i think my output shaft seal (where the front of the prop bolts to) is weeping oil out too so that'd probably be a bonus to do...

I've never ever done one so i have no clue about all the seals for the transferbox :/
 
last night after reading this i thought i would change the rear diff oil and haldex oil as the car was up in the air anyway as i am repairing the exhaust.

haldex oil was easy enough with the correct tool for the filter. Managed to drain the diff oil before realising i couldn't find my oil suction gun. So ordered a new one to pick up today with some GL-4 75w 90.
 
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