MC shift box hydraulic fluid

Ryandoc

Member
Messages
1,839
Folks

Is there any ‘special’ hydraulic fluid for the MC shift box or is it just the same standard recommended stuff, whatever that is ?

Reason I ask is that I had the classic won’t go into first last year and changed clutch and was brand new, haven’t driven the car much at all over winter but I seek to remember after one long drive of around 6 hours towards the end I had a tiny glimpse of it again but then never caused any issues like it did with a worn clutch.

So from my M3 days I know that there was an improved rear diff oil with a friction reducing magic potion that everyone sweared by, I’m wondering if even after hours of normal driving that the MC box hydraulic fluid gets just a little too viscous perhaps and again wondered if there was a wonder fluid kicking around?

Caveat, I may be talking total ******** but thought I’d ask.

Ta
 

azapa

Member
Messages
1,300
Tutela selespeed I think its called. Blxxdy fortune it costs too. There is a recommended LiquiMoly alternative if you dig around threads on here. Definitely change it though if more than a couple of years old.

Edit, either I've got the wrong name, or its ways cheaper there. My main dealer charged me 100 quid a litre!
 

Ryandoc

Member
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1,839
I just searched that about a tenner a litre ?? Would you have the name wrong perhaps?

It’s usually the way with these better fluids that are well recommended that dealers don’t recognise them isn’t it simply because they stick with what the manufacturer says and don’t do the after market thing so to speak ?

My fluid was replenished when they changed the clutch but like I say I remember after one 6 hour drive, a little if it spirited, that I saw a few box symptoms
 

D Walker

Member
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9,827
Not at all, but if there is a work around or if you are having same symptoms after clutch change I'm sure he will know why.
 

Zep

Moderator
Messages
9,110
The fluid should become less viscous when warm as should the gearbox oil, easing the shift. It could be the start of an actuator issue. I understand that it is possible to check the actuator leakage rate with an SD3 which is probably as good a place to start as any. It could also be an issue of air in the system, again the SD3 would help to pinpoint.
 

Ryandoc

Member
Messages
1,839
Sorry less viscous wasn’t concentrating, and I deal with viscosity a fair bit doh.

It’s only happened once since the clutch change and wasn’t a huge issue I just remember thinking hold on, but then never really took hold and this was after around 5 hours of driving.

I just wondered if there was a more ‘advanced’ fluid to be honest as would have got it stuck in, as I say like the BMW diff oil with the friction ingredient, it worked and a lot of people gave it nothing but praise
 

Ryandoc

Member
Messages
1,839
Not at all, but if there is a work around or if you are having same symptoms after clutch change I'm sure he will know why.

It’s definitey not the same symptoms, night and day and I only got a whiff off it after some of the spirited driving, which was after several hours of normal driving, sure you can guess what route I was taking Dave or at least my A to B points
 

conaero

Forum Owner
Messages
34,593
If it’s the gearbox oil you talk of, this is the second time tonight I have discussed this. It’s a diff oil modifier your after. Usual symptoms are after a gearbox oil change the diff moans on full lock. You add a small amount of the oil modifier and all is well and quiet.

This is what I used and it’s brilliant and I found it via an M3 Forum recommendation.:

https://www.eurocarparts.com/ecp/p/...MIn8-Oz5W42QIVCrftCh2IqwSOEAQYASABEgJ7_fD_BwE

If it’s the CC fluid I have little knowledge of the stuff but you could have an actuator issue or more so contaminated pots. Codes will be stored best get them read.
 

D Walker

Member
Messages
9,827
It’s definitey not the same symptoms, night and day and I only got a whiff off it after some of the spirited driving, which was after several hours of normal driving, sure you can guess what route I was taking Dave or at least my A to B points

I reckon I can guess, somewhere between stokesley and Helmsley or Guisbrough and Helmsley. Shush. Don't tell everyone.
 

CatmanV2

Member
Messages
48,543
Diff oil and hydraulic fluid for the change system are different. If it's one missed change, I'd not fret about it. I'll make more errors than that on the way to the station :)

C
 

voicey

Member
Messages
660
First of all the distinction needs to be made between the F1 fluid and the transaxle fluid (as Chris points out above).

Secondly please be careful adding friction modifier as it can inhibit the action of the syncros. I only use it when the diff is crying out for it and only then sparingly.

However not being able to select first when warm is highly unlikely to be related to the age or type of the fluids. You should talk to whoever installed the clutch.
 

Ryandoc

Member
Messages
1,839
Aye gents was just curious if there was a magic ‘non manufacture standard’ hydraulic oil for F1 box actuators, a race type fluid if you like, same as DOT for brakes or just used the M3 diff friction stuff as an example.

I’m not saying add friction stuff to hydraulic oil lol