6 speed 4WD gearbox and front diff oil change

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pj123

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I'm looking to change the oil in the gearbox of my 1999 s3 on 90k as the gearbox is stiff when cold and it didn't used to be.

I've read a bit about the gearbox and the front diff being connected and the way to change the oil is by removing drain plugs from both the gearbox and the front diff and refilling through the gearbox filler only. After refilling it was suggested to go for a short drive and then top up. Is this correct? I'm worried about draining two sides of a system and only refilling one side - and then driving on it?!?!. Why not just have one drain?

For ref the Audi Maintenance manual states:

Oil should be G50 SAE 75w-90
Audi only mention topping up the fluid and do not describe how to change fluid, but do specify that on the 6 speed A3 (Manual gearbox 02M) the filler plug must be renewed. Does not state this for 5 speed boxes.Tightening torque of filler plug to be 30Nm.

Thanks in advance for any help.
Paul
 
I asked the same question to Audi and got this response

"Filling Qty for the gearbox is 2.6 L so we will need to supply 3L cost £45.36 inc vat. ( I only have part numbers, no spec) There is no separate oil listed for the angle drive on the gearbox, it may be it shares the oil from the box, or it could be a sealed unit. "

Hoping to change the oil this weekend so anyone know the answer?
 
audi upgrades
pj123 said:
I asked the same question to Audi and got this response

"Filling Qty for the gearbox is 2.6 L so we will need to supply 3L cost £45.36 inc vat. ( I only have part numbers, no spec) There is no separate oil listed for the angle drive on the gearbox, it may be it shares the oil from the box, or it could be a sealed unit. "

Hoping to change the oil this weekend so anyone know the answer?
Click to expand...

a how to would be very good on this one pj so get snapping whilst u do the job m8
 
Happy to do a 'how to', but I really want to know the proper way to fill the front diff before i drain it. From the TT forums people 'go for drive to fill the diff from the gearbox'. Does this sound right?
 
dunno m8 your asking the wrong guy but im sure someone could pipe in thats done it b4 , if not you could try doing a help post and link it to this thread !
 
audi upgrades
This is probably what you want....

Audi Workshop Repair Guide said:
Gearbox and bevel box are filled together through the oil filler hole in the gearbox.

– Remove screw plug -arrow-.
– Fill gear oil up to lower edge of filler hole.
– Install screw plug.
– Start engine, engage a gear and allow gearbox to turn for approx. 2 minutes.
– Turn off engine and remove screw plug.
– Fill gear oil up to lower edge of filler hole once again.
– Fit a new screw plug.

a390278.png
Click to expand...
 
Thanks Tom, if the rest of that guide is available could you post?

Can someone tell me how to post attachments to do a 'how to'?
 
upload your pics to photobucket then paste the link into your how to, there are 4 seperate codes cant rem which one is the correct one but a bit of trial and error and you will soon get the jist of it
 
If you want to properly change the oil you will need to drain the bevel box as well as the actual gearbox. Just draining the gearbox without doing the bevel box leaves around 1/4 to 1/2 a litre of old oil.

I used about 2.6l of this, Mobilube 1 SHC 75W-90 fully synthetic, supreme performance commercial gear oil. Also used the same stuff for the rear diff which I think takes about a litre. I never renewed any plugs but did give them a good clean and check.

I used a suction gun to fill them up to the correct quantities then checked the front after a drive by undoing the filler plug whist the car was on level ground, put some more in it and then just let it drip out until it stopped, which means it's at the lower part of the plug. All instructions are in elsawin, not got it loaded at mo though.

I do this every two years and well worth doing in my opinion, just make sure the correct quantities are being used and don't overfill anything.
 
p.s always try and undo the filler plugs first then you can be sure you can fill her up again, the last thing you wanna do is drain it all out then realising you can't get the filler plug out or it's been over tightened and threaded..
 
quinnj2 said:
This might help you along :eek:) Photo: 01 - Transmission Drain Plug Loosened | Transmission Oil Replacement album | mcphill | Fotki.com, photo and video sharing made easy.
Click to expand...

As far as I can see this guy is now driving round with an underfilled gearbox!!

I will do these things differently:
1) Drive the car till its warm before draining the oil
2) After filling for the first time go for a 2 minute drive fo fill the diff from the gearbox then top up the gearbox.
3) Just to be safe will probably re check levels after a longer drive.

oh and use new gearbox plugs.
 
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Yeah doing warmup is a defo must, When I did mine I was anal and also checked the amount that came out in the first place. If you drain the bevel box then yes you need to drive it to then fill it back up and then top up the gearbox until it drips out the filler hole.

As long as the plugs are in good condition and are clean I see no point in changing them. The only one I have ever changed is the haldex drain plug.
 
all good advice anyway guys , what would be the reason to change the plugs if the threads and socket hole was ok it should be fine reckon they might be known as stubborn to remove which might lead to damage !
 
I can only presume the plugs and/ or the gearbox are made from a different material to the other A3's and that is why the manual only specifies the plug to be replaced on the 6 speed box. Maybe the plug crushes slightly to form a seal similar to a sump plug washer. Just guessing, it may become clear when I take the plug out.
 
So I changed the gearbox oil this weekend and there is a significant difference. When driven from cold there is now less/ almost no crunch from first and second which i was having a problem with, gear changes generally feel smoother and when backing off the throttle there is less vibration back through the gear lever so glad I changed it. The oil that came out was partly discoloured (11 years, 90k) but still had a hint of the same colour as the new oil. I used OEM oil.

Carried it all out using the tips highlighted above except for
- Didn't use new filler or drain plugs, the ones on the car were fine. (although looking at the plugs on the rear diff i will definitely replace those when i get around to it as they are seriously corroded)
- I bought a Draper Suction Gun, but would not use one again. Not sure if i had old stock but the rubber seal on the plunger seemed too hard and did not seal. As soon as it was upside down it leaked oil out of the breather hole at the back of it. If I was to do it again i would use a simple length of clear hose and a funnel. I will use this method for the rear diff as it guarantees getting all of the oil in and saves the mess of refilling a 500ml gun with 3 litres of oil. Basically it was messy!

The question about how the diff gets filled from the gearbox has been answered by Tuffty. Pic below from Tuffty shows diff and gearbox and the small holes with green seals allow oil to pass between the gearbox and the diff...

Gearboxanddiff.jpg


and this was the amount of metal stuck to the metallic sump plug on the diff

FrontDiffsumpplug.jpg
 
Bringing back a blast from the past as I'm planning on doing a fluid change of box, rear diff and haldex in one hit...

How do you drain the transfer box then? Same drain plug as the box?
 
Any oone used Fuchs Titan Race SYN 5 75w90 oil in gearbox ? Any feedback im thinking about change oil next month .
Thanks in advance
 
Gearbox oil should be 75w90 semi or fully synth but needs to be GL-4 spec not GL-5 spec as GL-5 spec can damage the syncros


<tuffty/>
 
Hi guys,

I purchased some fuchs tintan sintofluid sae 75w 80 gearbox oil for a different car, then sold it, will this be ok for bam225 6speed box

Opie oils said it was fine but thought id ask here too
 
Sorry to jump in on an old thread, but is there a separate drain plug for the transfer box in addition to the drain for the main gearbox?

Cheers.
 
Drysdaro said:
Sorry to jump in on an old thread, but is there a separate drain plug for the transfer box in addition to the drain for the main gearbox?

Cheers.
Click to expand...

Yes... bottom left of the end of the transfer box as you are looking at the inner CV

<tuffty/>
 
Mrt4x4 said:
Hi guys,

I purchased some fuchs tintan sintofluid sae 75w 80 gearbox oil for a different car, then sold it, will this be ok for bam225 6speed box

Opie oils said it was fine but thought id ask here too
Click to expand...


I've got this in my 6 speed FRK gearbox, it is a GL5 but modern ones don't attack the yellow metals. Some GL5 are too slippery and are more suited to diffs.

It seems VAG 5 speeds prefer 75W 90 and 6 speed 75W 80 .

With the B8 chassis A4 2.0 TDI oem is 75W 90 but due to the amount that are experiencing poor cold shifts have produced a oem 75W 80 .

It should of had this from new.
 
My Bevel Box Plug- 142k
No idea when it was the last change.
 

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It's probably never been changed. Gearbox oil is fill for life according to the manufacturer but as we all know after 100K miles and 10 years it's not as fresh as it could be. For the cost it's worth doing.
This was the Bevel box plug in my 2001 BAM TT gearbox with 88K on the clock.
IMG 1526

The oil that came out didn't look that good.

IMG 1529

The gearbox was a lot better after changing the oil. I went with 75w-80 Titan Sintofluid.
 
Can we find the actual photo's of the fill hole (on the top) of the 02A 6 speed gearbox please? Easy to get to?

Also, fill holes for the rear diff? Would this be on the side?

Is a turn of the wheels / 1 minute drive on the road, acceptable (to re-fill the bevel/ front transfer box) once the first 2.2 / 2.3 ltr of fluid is put back into the gearbox after swapping? Anything else to add on this?


Anything else to consider, whilst I plan to do fluids below shortly? To confirm...

  • "GL4" OEM for the front @ 3 litres?
  • "GL5" fully synth @ 1 litre for the rear diff OK?
  • Haldex oil out of the plaster gun/tube as normal @ 275ml?

Thanks guys.
Joe
 
02M , not A ?

Trouble is handbooks get out of date and better recommendations / superceded specs can be missed .

Like G50 , it's old...

What year and engine code ?
 
desertstorm said:
There's a picture of the fill hole on the front of the gearbox here
http://www.audi-sport.net/xf/threads/mk1-tt-225-track-day-car.319422/#post-3006144
Rear diff oil change
http://www.audi-sport.net/xf/threads/mk1-tt-225-track-day-car.319422/page-3#post-3125856
You should change the haldex filter as well. Although my 90K mile 15 year old car had the original metal item still fitted.
Click to expand...

Well, I've got the filter on the way +plus the funny looking multipoint L-shaped wrench thingy.

New nut & washer for the Haldex unit.
250ml haldex oil.

Semi synth GL4 (spec) for the front diff/ bevel @ x3 litres.
Semi synth GL5 (spec) for the rear diff @ x1 litre.

All review the earth straps & make sure it's all tidy / not leaking.

  • Shall report my findings soon, as the rear wheels are playing silly beggars juddering when turning low speed / on full lock etc.

Thank you everybody :)
 
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