I have a 2003 400 FIS.

I changed the rear axel and front differential oil a couple of days ago. I noticed that the differential oil look kind of milky chocolate colour. Looks like I had water (and mud) in there. My right INNER CV boot is torn and the grease has been leaking out a bit.

Will a torn CV boot cause water to enter into the differential? I checked the bladder above the differential and it looks ok.

Dennis

 

Spoke to the dealer about the water in differential issue: Water could get into the diff via the seals, drain plugs and the breather, or even condensation - especially if used during the winter. Since I bought this AC used and have no idea when the diff oil was last changed, I will just have to make sure my drain/check plugs are snugged and maybe also change my differential breather (breather doesn't cost much). Then I will monitor my diff oil and see what happens the next while.

Dennis

 

Better get that boot changed. From AC a kit is around $40 but you can get one (Wild Boar) from Pat's Small Engine for 1/2 of that.
http://www.psep.biz/store/arct...atv_cv_joint_boot.htm

The inner ones are not hard to change, the outer ones you still need to take the inner one off, unless you have a slide hammer to pop the outer CV joint off. But anyway the inner one is the easiest.