gearbox oil short?

[cypher007]

ive just changed my gearbox oil, and well it only took about 1.6L, but the book says it should take 2L. is there another drain plug hidding somewhere? or is there a section inside the gearbox that the oil gets trapped in?

p.s. the old oil had done 70K. it ran out like water, had the colour of treacle/bitter, and stunk something bad.

 

[cypher007]

ok

is it worth moving this to another section?

 

[Muttley]

Drain screw is in the bottom of the diff housing. Lowest part of the gearbox/final drive.

Seat docs say to refill the gearbox, first fill up so that oil is trickling out of the fill hole:

Car Must Be On A Level Surface!

then screw in the fill plug and run the engine with a gear engaged for two minutes. This is obviously designed for a car on a workshop lift. But I guess going for a gentle two-minute run would do just as well.

Then, back on your level surface, unscrew the fill plug and top it up again.

 

[cypher007]

cheers

thank you so much for replying. what i did was drain the gearbox using the big 17mm hex plug, in the bottom of the gearbox, was this correct? i did wonder this morning if i was meant to run it a bit to get the oil into an area where it cant be filled via the fill plug. i have been driving it for the last couple of days with the 1.6l in the gearbox, only on short journeys, i hope ive not worn anything .

 

[Muttley]

cypher007 wrote

what i did was drain the gearbox using the big 17mm hex plug, in the bottom of the gearbox, was this correct?

I haven't drained the gearbox on this car (2001 Toledo TDI, ASV engine EGS gearbox), in fact the last gearbox I did was on a Golf GTI some years ago.

The drain plug location is in the bottom of the diff housing, which is towards the back of the gearbox, between the drive shafts. I don't think there is any other hex plug in the bottom of the gearbox, but I'm not looking at one so can't be sure.

i did wonder this morning if i was meant to run it a bit to get the oil into an area where it cant be filled via the fill plug.

Just by looking at the gearbox diagrams, 5th gear is in a separate casing on the end of the box which doesn't seem to have any large holes between it and the rest of the box. Some oil could be trapped there, only circulating slowly through the bearings. There isn't a separate drain plug for this area.

How long did you leave the gearbox to drain? Not all of the old oil may have come out.

The gearbox capacity for the 02J box is listed as 2 litres.

i have been driving it for the last couple of days with the 1.6l in the gearbox, only on short journeys, i hope ive not worn anything

I doubt that any damage has been done. Everything in the gearbox has roller bearings, heavy tapered bearings for the shafts, needle rollers for the gears and big plain rollers for the differential.

It would be a good idea, though, to get back under the car and try topping up the gearbox through the fill hole again.

Remember, the gearbox must be horizontal for the fill hole to give the correct level. If you have the front end up on axle stands, you are likely to overfill the box, which will then probably leak into the clutch housing.

 

[cypher007]

cheers

i did do it on a lift at my friends house, has his own lift in his garage, how cool . anyway the only drain plug i could find was the big one, though there are some screws and stuff under there as well. i was going to run this oil for a couple of thousand and then drain it again, as im converting from Seat normal hypoid to Millers TRX fully synthetic, Millers said it would run ok, but Seat warn not to mix there standard hypoid with there performance hypoid in a box that takes normal hypoid. so now im wondering whether or not to drain it again or just top it up and run it for a couple of thousand miles, and then change it again? what do you recon?

p.s. mines a ASV with a EGS box also.

 

[Muttley]

Definitely recommend that you put it on the lift (lucky so-and-so), undo the fill plug again and top up, you may find that the whole missing 400ml goes in. In any event, this is the Seat recommended process - refill, run, top up.

If you undid the only plug with a hex socket fitting on the bottom of the gearbox it's safe to say that you chose the drain plug. Don't go undoing any other bolts!

What Seat says about oils is:

* There is a new mineral gear oil API GL4 SAE 75W (Hypoid) in accordance with TL 726 /Y. This type of oil can only be used in gearboxes where it is specified and must never be used in gearboxes that incorporate the previous oil API GL4 SAE 75W90 (Synthetic, high performance)
* Due to the incompatibility between these types of oils, they must never be mixed as they change the properties of the lubricant.

The prohibition is on mixing Synthetic gear oil with mineral gear oil, mixing will degrade the refill oil.

The EGS box is listed as being filled with mineral oil, SAE 75W (Hypoid). You need to find out from the Millers people whether there is any issue in mixing Millers with this oil, similar to the one flagged by Seat. Millers may not have the compatibility issue.

The other gearbox fitted to ASV Toledo's, EBF, is filled with SAE75W90 Synthetic, high performance oil, so it isn't a matter of year but of what the factory filled it with.

Did you, by any chance, measure how much oil came out of the box? If it was close to 2 litres, I'd say all you need to do is top up. If you're not sure, still top up now but consider changing it again soon (although that will be !ouch! expensive, using Millers as a flush).

 

[cypher007]

cheers

yeah ive bought a total of 4 1ltre bottles, as my friend was paranoid that it would take more than 2ltres. anyway im having to use the Toledo for the occasional short trip at the moment, as my friend has his four by four on the lift fitting some new gas tanks to it. when i told him the procedure he didnt think it was a good setup, he said do you have to put it in gear to drain it? also he said what stops you from overfilling it if there is no easy way for the oil to get in and out of the 5th gear section. is it worth topping up and checking it a few times to make sure the oil levels out? the next time i drop the oil is it worth letting it drain for a couple of ours?

millers said, after i contacted them with my concerns, that it would be fine. though im going to change it out after a couple of thousand steady miles anyway. so that hopefully by then most of the mineral oil will have been flushed.

 

[Muttley]

cypher007 wrote

when i told him the procedure he didnt think it was a good setup, he said do you have to put it in gear to drain it?

Of course not, you'd be running the gearbox with no oil in it.

also he said what stops you from overfilling it if there is no easy way for the oil to get in and out of the 5th gear section.

You are filling through a hole which is also the level setting: as soon as oil starts to come out, stop filling You can't overfill provided the gearbox is level. I'm not sure how isolated that 5th gear slot is, but even if oil has to get in via the roller bearing, a short session of running the box will warm up the oil and splash it around enough to level out the oil through the whole box.

is it worth topping up and checking it a few times to make sure the oil levels out?

Seat's procedure is fill, run, top up. I expect that with one top-up cycle the gearbox is close enough to levelled out that it makes no difference. As soon as you start to run it, the oil will be stirred up and splashed all over the inside of the box. My guess is that the oil level is set so that the roller bearings are partially under the oil surface at standstill, providing a slug of oil that gets carried round to lubricate the whole bearing at startup. After that it's all splash lubrication.

the next time i drop the oil is it worth letting it drain for a couple of ours?

Hmm. At a wild guess, I'd say 20-30 minutes, with a warm box (just after a run).

millers said, after i contacted them with my concerns, that it would be fine. though im going to change it out after a couple of thousand steady miles anyway. so that hopefully by then most of the mineral oil will have been flushed.

If Millers reckon it's miscible, then I'd not worry too much.

 

[muddyboots]

Interesting thread...I've been thinking about changing the oil in the box on my Passat.
There doesn't appear to be any scheduled change for gearbox oil, but after 100k miles it surely wouldn't hurt....

Do you know if the oil in the 6-speed boxes of the PD 130s is the same ?

 

[cypher007]

cheers

cypher007 wrote

when i told him the procedure he didnt think it was a good setup, he said do you have to put it in gear to drain it?

Of course not, you'd be running the gearbox with no oil in it.

also he said what stops you from overfilling it if there is no easy way for the oil to get in and out of the 5th gear section.

You are filling through a hole which is also the level setting: as soon as oil starts to come out, stop filling You can't overfill provided the gearbox is level. I'm not sure how isolated that 5th gear slot is, but even if oil has to get in via the roller bearing, a short session of running the box will warm up the oil and splash it around enough to level out the oil through the whole box.

is it worth topping up and checking it a few times to make sure the oil levels out?

Seat's procedure is fill, run, top up. I expect that with one top-up cycle the gearbox is close enough to levelled out that it makes no difference. As soon as you start to run it, the oil will be stirred up and splashed all over the inside of the box. My guess is that the oil level is set so that the roller bearings are partially under the oil surface at standstill, providing a slug of oil that gets carried round to lubricate the whole bearing at startup. After that it's all splash lubrication.

the next time i drop the oil is it worth letting it drain for a couple of ours?

Hmm. At a wild guess, I'd say 20-30 minutes, with a warm box (just after a run).

millers said, after i contacted them with my concerns, that it would be fine. though im going to change it out after a couple of thousand steady miles anyway. so that hopefully by then most of the mineral oil will have been flushed.

If Millers reckon it's miscible, then I'd not worry too much.

how far do you recon i would need drive to get the gearbox oil hot enough to drain it fully.

p.s. i had to look up what miscible meant .

 

[Muttley]

We are getting close to "how long is a piece of string" here. There are so many factors and I've not done this job myself. Best bet would be to feel the bottom of the gearbox and see if it's warm. There's no guarantee that all the oils will come out, though. The box is"filled for life" and oil changes don't figure in the service schedule.

 

[Muttley]

Muddy, I have no info on the 6-speed boxes so can't really help. I can see that the Passat's use completely different boxes from the Seat's, mainly 01 series rather than 02.

 

[cypher007]

update

well we tried to top it up this weekend, and it only took about 50ml if that. so im guessing maybe i didnt get all the oil out when i drained it. i think when i drain it next ill use a container that has markings on it for litres, and i think ill let it drain awful lot longer this time. i might even let the engine spin the gearbox very slowly, just to see if i can get every last drop of oil out of it. has anyone every come accross this weird problem before? is it worth me posting in say the Leon section, as there's probably more people in there who may have done this job before and found the same problem.

 

[Muttley]

I think you'll find that not many people have changed their gearbox oil. Still, it will be worth getting hold of any more experience that is out there.

You should be all right to idle the gearbox provided it's up on the lift. There will be no load to speak of. It will be interesting to see if anything more comes out of the box when you do this.

Keep the oil bottles you have just used and when you come to drain it, pour the oil back into the bottles. That way you will see how close to two litres has actually come out of the box. And it makes it easier to take it down the tip for disposal.