Evo 4 AYC oil change

Hi guys,

I am new to the evo scene but have recently bought an evo 4 rs, anyway i have a noise in the back 'suspension' when conering, I have read numerous threads and read that this can be due to the ayc. I have checked and topped up the ayc filler tank using dexron II ATF but still get the same. I was wondering how to bleed or do an oil change of the AYC to see if this helps.
Any other solutions would be appreciated as well.

Regards

If you have ayc then you have bought a normal gsr not an RS

What you need to do to cure the donkey noises is change the ayc bath fluid which is in the rear diff. Yes there are 2 lots of oils in the diff. One is your normal 75/90 gear oil or if you fancy silcolene Syntran and the other is the ayc fluid which is dextron III.

There are 2 fill bungs one for each oil the ayc one is on the rear of the diff just above the 2 bleed nipples and a bugger to get at so you should as a rule of thumb always remove the fill bungs before removing the drain bungs.

Thanks for the reply.
Well this car is a mystery, my log book says evo rs, if you do a hpi check it says evo rs, i dont have an airbag in steering wheel and the speedo only shows a top speed of 180 k/ph (about 115ph) yet i have ayc (or at least I think I do) as there is a filler tank in the boot and a dash light! Weird.

Yes the sound I get is like a 'donkey', I get it worse when turning right and only when the car is warm. Sometimes the noise sounds like wheels screaching as well, and thats not because i'm driving like a nutter, thats at normal cornering speeds.

Thanks for advice on emptying the AYC, when thats done do I just refill it using the filler tank in the boot? And do I have to bleed the system? How much oil does it take to fill and what is the difference between dextron II and dextron III? Sorry for all the questions but AYC is a total new thing to me.

cowen1000 said:

Thanks for the reply.
Well this car is a mystery, my log book says evo rs, if you do a hpi check it says evo rs, i dont have an airbag in steering wheel and the speedo only shows a top speed of 180 k/ph (about 115ph) yet i have ayc (or at least I think I do) as there is a filler tank in the boot and a dash light! Weird.

Yes the sound I get is like a 'donkey', I get it worse when turning right and only when the car is warm. Sometimes the noise sounds like wheels screaching as well, and thats not because i'm driving like a nutter, thats at normal cornering speeds.

Thanks for advice on emptying the AYC, when thats done do I just refill it using the filler tank in the boot? And do I have to bleed the system? How much oil does it take to fill and what is the difference between dextron II and dextron III? Sorry for all the questions but AYC is a total new thing to me.

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The bottle in the boot feeds the pump which run the clutches inside your rear diff. These clutches are sat in a bath of the same ayc fluid which gets quite dirty and debris from the clutches and old oil can commonly cause these noises. Remove the fill bung located at rear of diff, remove drain bung till all fluid is out then replace the bung. Put say 1/2 litre in the fill hole then rotate the rear wheels a few times then let the fluid out replace bung then fill with oil till it runs out the hole. This is quite fiddly due to poor access to the hole. Then re-fit the fill bung.

Rs models came without ayc, aircon, air bags, electric windows, short ratio gearbox also. Rs II had the toys like airbags, electric windows, but still no ayc.
You have a gsr for sure. My old VII was down as an rs II on log book but was just a normal gsr. The 180 kph should be converted to run in mph and will prob sit at around 3500rpm in fifth gear at 80mph ish.

Thanks for the advice mate. I will do the AYC oil change on weekend.

What is the difference between Dextron II and Dextron III? I have been topping up the ayc filler bottle with Dextron II, is this ok?

cowen1000 said:

Thanks for the advice mate. I will do the AYC oil change on weekend.

What is the difference between Dextron II and Dextron III? I have been topping up the ayc filler bottle with Dextron II, is this ok?

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Let us know how you get on, as said undo the fill bungs before you undo the drain bung ans youll need a thin tube to squirt the fluid into the diff.

All will become apparent when you get under and see. The ayc bungs are written on the diff with arrows

No idea but I was told by a Mitsi service manager to use dextron III

You shouldn't need to top the bottle up in the boot as it's a sealed system unless you have a leak

I will let you know how I get on, on the weekend. thanks for the info.

I will get dextron III

I hope this is the cure and there isnt anything more 'sinister' cos I know these cars can cost a lot of cash to get fixed.

cowen1000 said:

I will let you know how I get on, on the weekend. thanks for the info.

I will get dextron III

I hope this is the cure and there isnt anything more 'sinister' cos I know these cars can cost a lot of cash to get fixed.

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Same happened on my mates Evo V and I've heard of lots of other people having same problems and it cured the noises.

As I said once you drained it put the drain bung back in and put half a litre or so in then rotate the rear wheels a few times then drain and re-fill.

2 litres will be plenty

Thanks mate

Hi, I changed the ayc bath (very fidly job due to access) and that indeed cured the donkey noises when cornering etc. I still have a whirring noise when driving which gets louder with speed, it isn't extremely loud but is loud enough to here. The sound is coming from the reaar diff area. Any idea's on this??

ah good, glad it done the job

wheel bearing possibly ??

wheel bearing possibly ??[/QUOTE]

+1 on that, was thinking the same. Worse case could be the diff.! Hope not though. Wheel bearing cheaper fix

Now all he gotta do is work out which side which is hard on a Evo cos the wheels don't exactly spin very freely when trying to rotate them to listen for a rumble.

B6lee said:

Now all he gotta do is work out which side which is hard on a Evo cos the wheels don't exactly spin very freely when trying to rotate them to listen for a rumble.

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I know what you mean Lee. I managed to find mine cos it was LOUD, think I still have it somewhere (kept it for the abs sensor and handbrake cable)

m7gsr said:

I know what you mean Lee. I managed to find mine cos it was LOUD, think I still have it somewhere (kept it for the abs sensor and handbrake cable)

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Bought the whole hub did you ??

yep, I think I got it cheap. Some guys wanted £130 with the abs sensor and £80 without. I got the complete hub with abs sensor and handbrake cable for £50

Easier to change the lot as sensors can be a right pain in the ass as you found

That was a bargain cos the sensors ain't cheap and people know it. :meh:

B6lee said:

That was a bargain cos the sensors ain't cheap and people know it. :meh:

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I have a sensor there if anyone needs it. Might not be good because the light was on at the time (or was it),can't remember. Think was the ayc light on only.

It was the ayc light stayed on and kept saying sensor as a fault (car drove perfect though, no ayc issues) weird

I had my rear bearing go and I thought it eas the diff. You can't here the noise by rotating. I had my car up on a 4 post ramp and drove it in gear and still no noise. Because thete is no pressure on the drivetrain it is hard to find.