XC70 2003 Lost drive to rear wheels

Dennis59 · Post by **Dennis59** » 30 Oct 2009, 19:45

150K and recently changed rear wheel bearings but I was stopped at a light and when I went to take off I hear a snap. Now it appears that the AWD isn't providing power to the rear wheels. I jacked up the front and sure enough the front wheels spin but nothing to the rear wheels. I've check fuses but have not crawled under the car yet but I can see that the drive line is not turning. Any ideas? "Transmission Service Required" message has been on for quite a while as well as the check engine light which came on at exactly the same time. I am also getting a vibration when driving and I think it got a little worse when I heard the snap. It could be wheel balance as I know that need to be done but it could also be front CV. When jacked up with wheels turning the right front wheel bounces but not the left. All ideas are appreciated.

commlend · Post by **commlend** » 30 Oct 2009, 19:56

From what I understand, they are actually limited slip differentials. It is not a true AWD vehicle. The rear wheels would not spin unless the car sensed they needed to.

Dennis59 · Post by **Dennis59** » 30 Oct 2009, 19:59

That might be but with the front wheels suspended and the back wheels on the ground not moving it would sense that the power needed to be supplied to the rear wheels. I've also accelerated on slick ground and had the front wheels spinning and no back wheel power there either. They aren't working.

Dennis59 · Post by **Dennis59** » 01 Nov 2009, 11:08

Does anyone know exactly how the AWD works on these cars? I know its electronic but are there sensors somewhere that activate the electronics to engage the rear wheels. It was always very obvious in any slick situation that the rear wheels were driving. Everything else seems to function fine and know new messages show up. Help!!!

Post by **OEMVolvoParts** » 02 Nov 2009, 09:09

Your angle gear is probably fried. Could have been caused by a few things, low fluid level, lack of fluid change, or wrong sized tires being used. Next time you have it in the air, verify that the angle gear is not spinning at all. Not just the driveline, but the angle gear itself. If it is not moving, it is not a cheap fix.

commlend · Post by **commlend** » 02 Nov 2009, 20:22

Check this out. I think it may be your situation.

https://www.matthewsvolvosite.com/2008/1 ... -engaging/

Dennis59 · Post by **Dennis59** » 07 Nov 2009, 12:39

With the assistance of those on this site I have made the following assessment. Any input is appreciated.

I've pulled the skid plate and checked the angle gear for rotation when it is running in drive. the angle gear does not appear to be turning. Both front axles are turning but the angle gear is not turning and the drive line is not turning. I do not see any solonoid attached to the angle gear box. The only solonoid I see is attached to the rear end. I can turn the drive line with my hand even though both rear tires are on the ground. This makes me think that the control solonoid for the AWD is indeed the one on the rear end and that the drive line should be engaged all the time and turning and that the rear wheels are engaged in the rear end by the solonoid. I would now assume that the angle geer is indeed what is not operating. What do you think?

How difficult is an angle gear or gear box to replace?