Diff oil change

[Simon 3.2M]

Not due but looks like it was worth doing!

IMG_2053.JPG (197.95 KiB) Viewed 790 times

IMG_2054.JPG (221.13 KiB) Viewed 790 times

[GuidoK]

imho that looks due.
You can see quite a bit metal content in the oil.

[Simon 3.2M]

That's contaminants in the bowl mate, UD didn't clean it out beforehand

[GuidoK]

How do you know?
If you want to say something about the state of your oil, then why did you use a dirty bowl? And how do you get that contaminant so mixed up with the drained oil?
The z4m has a clutch lsd, so you want to be alert to these things. This is one of the aspects (probably the only one) to analyze the state of your clutchpack without opening up your diff (and that is a serious and difficult job).

[Simon 3.2M]

How do you know?
If you want to say something about the state of your oil, then why did you use a dirty bowl? And how do you get that contaminant so mixed up with the drained oil?
The z4m has a clutch lsd, so you want to be alert to these things. This is one of the aspects (probably the only one) to analyze the state of your clutchpack without opening up your diff (and that is a serious and difficult job).

Sorry boss!! I've decided to change my oil as I wanted to, even though it's not due for another 10k+, this is my decision and gives me an interim service. I will be doing the same with the gearbox oil as this is something I do with all my cars - too many years as an RAF aircraft technician over servicing jets! I was making a general comment about the colour of the oil and just sharing with fellow members / enthusiasts. I take your comment about the fact that I cannot see if the clutch pack is failing however, if they are, what am I supposed to do? If they are going to fail they will fail regardless of wether new oil is added. If there was evidence of them failing I wouldn't drive the car any differently. A diff rebuild will be done in 12 months time and factored into the list of maintenance for the car - at 100k it is something to be aware of. I watched the oil drain and I was happy with what came out and don't have any reason to suspect the diff is fatigued or on the point of failure.

[GuidoK]

If you dont want members' opinions, then dont post the pictures on a forum.
All I see is a tub with quite dark oil with a thick haze of conterminants resembeling wear particles.
You do with that what you want.

[Simon 3.2M]

Guido, please don't get upset and defensive - you comments were appreciated and welcome and I thank you for them. I must point out that the original post wasn't actually requesting opinions from people, it was more an informative post stating that I had changed the diff oil and the stuff that came out, whilst not due a change by the inspection date, was probably worth changing and a wise precaution. Others after looking at the post may or may not want to change their oils, it's their preference.