About a year ago, I acquired my mom's 89 240 volvo wagon, 143 K, generally great cond. & maintenance. I've ridden in this car a fair amount over the years, and have a pretty good sense of what this car is supposed to sound like. A few months ago, the 150 K service was done by an experienced Volvo mechanic, and shortly thereafter (but possibly coincident) I noticed a high-pitched whine setting in, faintly at first, at 62-65 mph on the freeway, in either 4th or 5th (manual transmission, non-auto overdrive). This definitely seems outside of the norm. Now this sound is kicking in at 60 mph or a little less and is getting somewhat louder, however pitch remains high. It is independent of road surface type or condition. Good Michelin tires on the car. Don't think it's a function of moisture or vibration on the antenna, as once the whine kicks in, it seems to increase in direct proportion to rpms, and decreases as rpms decrease, but the whine doesn't stop if I take my foot off the accelerator and allow the car to coast. Emergency brake is functioning properly, and not accidentally or partially engaged when sound is noticed. It doesn't seem innocuous, so I have been dropping my speed below that point until I can figure out what's going on. Now I'm getting passed left and right on the interstate, which is great for gas mileage, but tedious as heck. At 154K, car was serviced for new brakes (front and rear pads, rear l/r calipers, front rotors). No stones in brakes. I mentioned the whine, and Volvo mechanic checked & repacked front bearings, which were found to be OK, but sound persists. (sound seems front right). Ball joints were also checked at this same service.

I can't for the life of me figure out what might be causing this sound, and would like to have some ideas next time I go to the mechanic, hopefully to be able to start at the simplest/least expensive possibilities first. My spidey-sense tells me that this is definitely not a good thing. Any thoughts greatly appreciated. Thanks.

 

It may be good to check fluid levels in the trann'y and the diff.

 

Thanks Joe- Will check them in the a.m. (whoops, it already is...) and let you know if that did it. Bev

 

You didn't mention disengaging the clutch and noticing change. If the noise is speed related, check the drive line including center support bearing on the drive shaft.
Don't forget to check all exhaust supports that may lead to some rubs and noise transfer to the body.
Try listening for changes with clutch depressed and also with the trans in gear or not.
Pick the speed or RPM where the noise is worst and investigate all changes and inputs.
Ed

 

These are all good ideas. Good luck...the last time I had a worrisome high whine it turned out to be my mother-in-law in the back seat! A bad carrier bearing would have been preferable!

 

Thanks, all, for your ideas. Some time demands have constrained my troubleshooting, but I am pursuing the ideas you so kindly put forth. My sympathies with the mother in law situation !