It's not poo...
 

Can someone give me an idea of what this is and where it possibly came from. It appears to be grease?
https://cimg2.ibsrv.net/gimg/www.nor...bff3a9d49c.jpgFront right corner of an '03 MCS
https://cimg5.ibsrv.net/gimg/www.nor...f9b87fb46a.jpg
https://cimg6.ibsrv.net/gimg/www.nor...22e5d5c3d1.jpg

Water + grease and spin really fast give you milkshake. AKA emulsion.

Looks like the CV boots are dead or dying. They are a normal wear item. Had mine replaced at 104K miles.

Alrighty then. Time to research maintenance tips to find out more stuff to replace or repair. $$$ time.

In my opinion, and for the amount of work that's involved to replace the worn boots with new ones, you're better off replacing the entire axle with a re-built axle that will come with a warranty.

Either way, the axle needs to be removed, so your choices break down as follows:

A) If you replace the boots only (about $25-30 for the kit), you'll need to disassemble the axle, clean-out, then re-pack the axle joint housings with new grease, replace the boots & clamps, reassemble and throw it back into service with the used axle carrier bearing and internal rollers at less than 100%. This approach is much more work than just replacing the axle.

or...

B) You can purchase a rebuilt axle (I'd suggest by Cardone Industries), where all components have been replaced, and you'll have a warranty. A rebuilt axle will cost you about $50, plus a $35 Core that will be refunded when you return your nasty leaking axle to them.

That's what I did when my passenger-side boot leaked and created the exact same mess that you're seeing now.

PM me if you want the information on where I sourced my axle.

Replace axle
 

Thanks so much. I'll replace the axle as a precautionary measure. Are there any other suggestions while I have everything apart?

There are always additional tasks that can be more easily accessed whenever parts are removed from our MINIs.

With the passenger axle removed, you have great access to the oil filter housing, which is probably in need of a gasket change. If you do remove the housing, make sure to also replace the two oil cooler o-rings while you're there.

Inner ball joints are also more easily replaced with the axles out of the car, as you can get a socket on the front-most bolt and lift it out.

You might also want to think about replacing the axle output shaft seal on the gearbox, as after I recently replaced my passenger axle, it began to leak in the weeks to follow. As soon as the frigid weather lifts here, I'm going to need to pull the axle a second time to replace the seal.

Dang CV boot cracking up and leaking down. You can do just the boot, but some people just go ahead and do the axel since you are in there.

I just spoke of you yesterday to my wife. I ordered a couple parts from ECS Tuning this weekend. I have more on my list in the coming months.

Thanks for the orders and future order! And glad you talked to your wife. ;)

I am here to help.