Hi

my mechanic put 75w90 oil in haldex,he did that mistake and after few days i changed it again and added Febi haldex oil

but in rear diff he didnt change the oil,4x4 works good thanks good but in my book i havent seen written that have changed rear diff oil lately

what should i do

haldex gen 4 is in my car

You are unlikely to see much about a schedule for the rear diff oil change.

But i would think that use like maybe doing water crossing / wading, launching boats in fresh or salt water or offroading might have owners think about having it done when ever they think.

Certainly within 8 years or 80,000 miles even if just used for road use,

Diff oil is for life or until a numpty like me drains it thinking he was draining the Haldex Fluid.

 

The original 75w90 that I mistakenly drained came out looking and smelling like brand new after 79K miles, that was my first clue that I had made a mistake.

 

The rear diff is freewheeling pretty much all the time, power is mostly transmitted in straight line conditions and the planet gears are not revolving and transmitting zero torque, even if it had spent its life as a drift car the torque transmitted is only 50%.

Not entirely relevant but what about the gearbox. I changed mine @16K and it was like dirty water, refilled with a higher grade( not advise 🥴) 

Rated for the life of the vehicle.

 

No harm in changing it if it floats your boat but at only 16k miles????????????

Edited 24 August, 20241 yr by J.R.

It was thin enough to oil a sewing machine 😖🥴.     Did you see my other post today re your advice ,( can bus)  which I eventually followed ?   Didn’t help but thanks anyway, any other thoughts gratefully received. 🌝

The thinner the oil the better for both engine and transmission as long as it can continue to lubricate under operating conditions, its what all manufacturers are trying to achieve.

 

You say that you don't advise (others) to use a higher viscosity oil as you did, what were the consequences?

Non, the box still operates flawlessly and is still in there, just don’t want someone to get the idea and go mad— 75- 90 EP anyone🥴 any more thoughts on my long running drain problem? 🌝

On 11/08/2024 at 23:44, Argjenddre said:

Hi

my mechanic put 75w90 oil in haldex,he did that mistake and after few days i changed it again and added Febi haldex oil

but in rear diff he didnt change the oil,4x4 works good thanks good but in my book i havent seen written that have changed rear diff oil lately

what should i do

haldex gen 4 is in my car

How did you realise? Did you query the itemised oil in tye receipt? You may want to flush it again by draining a second time after a decent drive so warmed up.

 

The thing is the haldex oil has friction modifiers in it to aid with the clutch pack operation. Your lucky I guess that the haldex clutch is generally decoupled so if it wasn't called for in the day you had the wrong oil in, probably hasn't burnt the clutch packs.

 

But I'd probably do a second drain and refill but that's just me. How much did you drain / refill about 800ml if I remember. If you remove the pump, a good idea to recheck level after starting car as pump will reprime and lower level slightly...