The last few weeks I've noticed a knocking from the center, front of my roo on acceleration. I thought at first when the sound was faint that is was coming from the driver side wheel, but I now believe it’s more in the centre of the car…under the engine and a bit further back toward the driver. The sound is a hollow knocking that doesn’t speed up a whole lot with acceleration but is loudest when the cars is under load….accelerating from a stop, going up hill at lower rpms. It’s loudest at around 2000-2500 rpms and gets quieter as the car speeds up, but it is still there. It’s not 100% consistent either. The instant I take my foot off the accelerator or even lighten it up a bit the sound decreases or goes away. I don’t hear it in first gear at all, but in 2,3 and a bit at 4th.

 

My roo is a 1998 Legacy, standard with about 160,000km.

 

Any thoughts?

 

Thanks!

Urban Coyote

you need a new cv axle, now to determine which one - passengers side or drivers side. take a look and see if the boot is broken or leaking grease on either side. sounds like drivers side based on your description, but definitely want to make sure before going ahead with the work. and have this fixed as soon as possible, this can get worse rather quickly and all that vibration is not a good thing.

If it is a cv axle, will it be a big job to replace? What cost(ish) would I be looking at?

they're easy. generally $150-$200 to have a new axle installed. $60-$100 for the part and $75-$100 for labor. i would only use a Subaru axle or MWE, aftermarkets are prone to far more problems. yes, i know people will pipe up about it "i have an aftermarket and it's fine", i know people use them and i've seen them used before, my point isn't that all aftermarkets blow up, but that they are far lower in quality.

 

if you mean to do it yourself, they aren't that hard but there are some tricks involved so to speak. once the wheel is off there's not much more to it than 3 nuts - 1 axle nut and two strut tower bolts. a little more work after that, but not much. but....you have to get the axle nut off (one of the hardest to remove on the vehicle), uncrimp the nut, line up the cv axle splines...things that aren't that difficult but you need to know about at least.