Your Geo is a nicely put together vehicle, and it's convenient and easy to get a good view of what could be going on with your Geo axle assembly. And, if you've been experiencing some of the symptoms that could indicate that it may be time to consider replacing your Geo axle assembly, you may want to take a look under your Geo sooner rather than later. Assuming you've kept up with your tire maintenance - making sure, for example, that they are properly balanced - and keep them inflated to the recommended pressure, uneven tire tread wear can indicate that you may need a new Geo axle assembly. Other symptoms can include a significant vibration while making turns, often accompanied by a distinct clunk or popping noise. This is often more pronounced while moving the vehicle in reverse and is a strong indication that the time has come to install a new Geo axle assembly. At the very least, you should take a look underneath your Geo and check the condition of your constant velocity joints, otherwise known as CV joints. These, with the clean design of your Geo, will be very easy to see. If, upon your inspection, you see that the outer covering of your constant velocity joints has been worn so much as to expose the inner parts to the elements and the debris of the road, it's often a good idea to go ahead an install a new Geo axle assembly, as there's a strong possibility that gritty, damaging dirt has worked its way up through and just changing the CV joints will not resolve the symptoms and sounds that you're experiencing with your Geo.