2005 XC90 AWD: Occasionally, when I am backing up something in the rear end seems to try to lock up. It seems like it is skipping or what you would feel if a chain jumped a sprocket. If I rake the car out of reverse and then shift it back it works OK. Any ideas?

 

Do you set the emergency brake when you park the car? If so next time don't set the brake when you park (if it's a relatively flat area) See if the noise occurs the next time you reverse.

 

No, it has always happened on level ground so far. It is almost like a gear problem in the differential or whatever they call it for AWD. But it drives perfectly in the forward gears and only deas it once in a while. Thanks for responding.

 

Your Haldex probably needs filter and fluid change.