AYC and Diff fluid Drained - Incorrect fluid levels found

[pretzil]

Okay so, to recap from the stupid questions thread:

Okay, so, I was under the car today and I think that my rear diff is slowly leaking ayc fluid, probably been doing it a while as the diff is fairly caked up.
I'm going to have a go at cleaning it up to see if I can see where its coming from, are there any likely leak sources?

Mine has been leaking in the same way, since forever. There is a breather on top (tricky to access even just for inspection). If your diff was overfilled it could be coming out there. One other possibility (unverified) is that there is a hairline crack inside the diff - there are two chambers, one for gear oil and one for AYC - and pressure from one side is bleeding through to the other, causing overflow. This was suggested to me by an EVO specialist workshop; however they have since been proven to be careless in under- and over-filling diffs and gearboxes so I'm sceptical of their diagnosis.

Anyway aside from a small and very slowly spreading oil stain on the garage floor, there have been no ill effects from my diff leak.

If you pull your AYC fuses you'll be fine to drive it, nothing will get damaged.

if 2 different fluids mix together, that'll cause chaos with your pocket..

Upon inspection and cleaning, it seems the leak is coming from on top of the diff where the breather is.
Now, today I finally got around to draining the diff fluids... with 'interesting' results...

The car was approximately level on 4 x Axel stands,
When I removed the DIFF OIL FILL, about 400ml of fluid came out.
Then I removed the DIFF OIL DRAIN, and about 550ml came out

Then I removed the AYC DRAIN, and approximately 450ml came out

I don't like these numbers... They seem a bit different to the official figures
According to the How-To:

Supplies,
1. 0.39 ~ 0.43L of 75w90 GL5 Transmission oil (I used Castrol Syntrax 75w90) for the diff
2. 0.65 ~ 0.7L of SPIII Automatic transmission fluid (I used the Mitsubishi stuff) for the AYC Speed Gear.

So, these are a some of the scenarios going through my mind:

1. The previous owner had too much oil in the diff and not enough in the ayc, I havent noticed any diff symptoms and if I add the correct amounts all will be good (Wishful thinking)
2. There is a crack, the 2 fluids are mixing and its a miracle the diff hasn't completely self destructed yet. I need a new diff.
3. In the meantime I should fill them with the correct levels, try it out, and drain it again in a week or 2 to see the results.

So, does anyone have any advice, ideas, tips, ominous foreshadowing?

Thanks

 

[Guest]

Put the correct levels in and measure it again next time. It wouldn't be the first time someone has incorrectly filled them. Just take it slow refilling and measure how much you are putting in, don't just go by the backflow out the filler. I use a hand pump and fill the bottle with the correct amount first so that I know exactly what's going on. The transfer case in particular needs special attention.

 

[pretzil]

Okay, thanks for the advice.

Well, I would have followed those instructions except that these things Orcon-Siphon-Pump-1-8m from supercrap auto are bloody useless and don't actually let you hand pump with the bulb, its just a pathetic imitation of a jiggle siphon for people with no arm strength.

And these things: SCA-Suction-Gun-Plastic-400ml are almost useable except that they are too hard to get into place for the AYC fill, dont hold enough and they leak out of the plunger end...

Does anyone know where I can get one like the first one that actually pumps, like a primer bulb on a boat fuel tank? With a one way valve etc?
Either that or I will buy a tom thumb pump bottle like I should have in the first place.

Argh, what a bloody day, there's a lot to be said for having the right equipment... I even thought I was prepared this time :angry:

 

[Guest]

I use the Tom Thumb pump. Still a little fiddly for the AYC filler due to limited access, I trimmed a bit off the hook. But the other fillers are fine to hook into. It pumps very slow, but that's actually a good thing for getting the levels correct.

http://www.supercheapauto.com.au/on...mb-Pump-Utility-1-Litre.aspx?pid=284708#Cross

And this is a DIY solution I found on another Evo forum (maybe EvolutionOz?). It's made from a garden sprayer, never tried it though... I imagine it would still be difficult to fill the AYC side of the diff.

 

[naughtika]

never thought that those type of pumps would work.. thought that the oil's too thick for it..

anyway.. Rick, about your dilemma.. what I used to do when filling up, I'd fill it up for about 200-300ml cause I know that's about the right amount without spilling it. then I would let it rest for about 3-5 minutes then i'd add 50-100ml then rest again for 3-5 minutes.. bit slow but enough for you to have a micro sleep while under the car.. lol

 

[pretzil]

anyway.. Rick, about your dilemma.. what I used to do when filling up, I'd fill it up for about 200-300ml cause I know that's about the right amount without spilling it. then I would let it rest for about 3-5 minutes then i'd add 50-100ml then rest again for 3-5 minutes..

Which oil is that tip for? I got one of those tom thumb bottles, measured each of them out to the max specified levels and pumped each in fairly steadily, neither showed any sign of leaking back out... It was 700ml of SP3 for ayc (the hard to get at plug) and 430ml of syntrax for the diff (the easier one)

The car is fairly level on the 4 stands, but I'd imagine if I was filling till it drained out I would have put a fair bit more in.

 

[naughtika]

Which oil is that tip for?

any.. rear diff (non ayc and ayc) transfer case, manul box or auto..

 

[pretzil]

Okay, so, one year later (holy crap its been a year?), today I change my fluid again... Should have done it sooner but been lazy doing other mods...
The car is not up on 4 stands this time, just blocks at the rear, since I feel that if I measure it with the tom thumb, it should be correct since I am not relying on back flow out the filler.

To recap, a year ago I changed my diff oils, and filled with explicitly measured amounts of fluid.

Just drained the Diff Oil, since the fill plug had been weeping a tad. 600ml came out, very dark in color, reddish tinge (uh oh), not much metal on the magnet plug, the usual gunk and one 5mm hair size metal slither.

Wasn't planning to change the ayc clutch pack fluid, think I will now though, just to see how much comes out, if I still have enough SPIII in reserve from last time.

Time to start chasing an evo S-Ayc diff?
Or no symptoms = no problem?...

Opinions?
Thanks

 

[naughtika]

I think its up to you if you would like to play it safe and start looking for a replacement diff. I would think this way if I drive my car more spirited everyday or just once in a while..

Also you need to consider the age of the car, mileage done cause sooner of later something will let go... unfortunately

 

[pretzil]

I have a policy against replacing without upgrading, so if anyone hears of a super-ayc diff around qld, or an evo 8/9 being wrecked, let me know.
Been watching evoooz for sale section for a while.

Can anyone tell me what's involved in the swap? It's a full case swap isn't it, with new bushings or something?

(BTW, don't recommend an open or LSD diff thanks, I love ayc too much)