oxygen sensor -replace or wait?
 

1995 E420 with 60,500 miles. Have done all 60K service except replace oxygen sensor, which is called for on maintenance schedule. Having no problems but wanted opinion as to go ahead and repalce. I do a lot of my own maintenance and is this something I could handle? Anything weird to look out for?

Thanks

Most people want to wait until there is a problem! CHECK ENGINE!
But if $$$ isn't a problem then you SHOULD replace the sensor as overall you will have a cleaner running engine.

Thanks M.B Doc. Another opinion if you don't mind on another subject.

I think for now I will wait because now I need to have a "whining" sound in the rear checked out. Sounds like I have snow tires on and goes up and down with acceleration.

Guessing rear wheel bearing. Becomes noticable at about 25MPH and increases with speed but then when at say 60 -70 MPH hard to hear due to normal road noise.

Seems too early for rear wheel bearing problem or have you seen this before? I thought it was a bad tire but just had new tires and alignment and sound still there...been doing this for about a year but I have only put about 3,000 miles on car in last year.