1996 RAV4 drive train noise

July 9, 2016

I have owned an indestructible 1996 RAV4 for about 10 years. Automatic, front wheel drive, gasoline, 125,000 miles. Great car. I drive only 1000 miles a year.

For the last year, it has been increasingly making a distinctive front drive train noise. Kind of like "waa waa waa" in a manner which correlates to car speed. It is not a ticking, knocking or bumping sound, not is it a rattle. It does not vary with engine speed or which gear the car is in. It does not change when the car is turned. It does not make any grinding or bumping noises when turning at low speed, like a CV joint might make. It drives perfectly, other than this sound.

My thoughts are wheel bearings or some bearing in the transmission/transaxle which is related to an output shaft (because the noise correlates with speed). Another possible thought is a bad tire? The noise seems too loud for this to be the case, but it is similar to a noise I have heard from tires.

Searching around some, I have not seen this discussed, so I fear it may not be an obvious or typical issue. But I wanted to ask if anyone is familiar with this, and/or what should be my repair sequence to try to see what this is? Or, should I do nothing and wait for it to develop further? Or, replace tires and CV's just in case?

Thanks very much.

July 9, 2016

Tyres would be my first call. If you've had the vehicle for 10 years, only doing low mileage, then the tyres have probably been stationary for long periods and will deteriorate especially in strong UV rays. Tyres are like cars, they work better when they're used regularly. You could have tread separation or other problems,

Examine the tyre sidewalls for any signs of cracks etc then jack it up one side at a time, fix a pointer (eg axle stand) and turn the wheels by hand checking for any eccentricity or wobble. Tread separation is where the tyre tread starts to separate from the main tyre carcass. If at all in doubt fit new tyres..