My car's been making this weird noise from the rear and it's most audible when cruising/coasting 35-45 mph in fourth gear or around curves. It sounds almost like you're getting a flat tire, except that it's not that loud. There's also this "tugging" or "pulling" sensation from the rear when I go above 50 mph. It feels kind of skittish and jittery in the rear--kind of like the same sensation from a rear-drive, rear-engined car like a Porsche at highway speeds. I did a search and all I could get was threads on rear differential problems where other owners describe similar signs/symptoms.

Anyway, I decided to bring my car in to 128 Liberty Mazda in Wakefield (for Mass people) to have them take a look at it this morning. They had the car for the whole day, but the couldn't find anything wrong with it. The service advisor told me that some tech drove my car for 7 miles but still couldn't hear the noise I described. Since my car has the RB exhaust on it, it's kind of hard to hear the groaning/whining noise. I'm 100% positive it's there, but I don't know how to convince them that it's there.

I was told to come in tomorrow and go for another test drive with a tech. If they still insist that there's nothing wrong with the car, what can I do? Should I ask them to check the differential fluid? If they refuse, should I ask them to change the fluid and I'll pay out of pocket for the work? I'll then ask them to see the drained fluid to see if it's all black and has metal bits and pieces in it.

If the same problem worsens after my warranty runs out this August, do I have a case for warranty work because I complain about it and have it documented now?

Please give me some advice. Thanks in advance.

it kinda sounds like a similar situation i ran into with my cousin's RX8.... his DSC was acting a fool for some reason... do any of your traction or dsc lights come on at any point for no reason or as accelerating other than a quick shift traction break? His would only do this while turning and sounded like it was in the rear. We reset the DSC by holding the button for 10 seconds and it went away. Hasnt come back that i know of....

reset the dsc? just to see.

Thanks all for your replies.

I will try doing what everyone suggests tomorrow.

I got the car back from the dealership this morning. The service advisor and the tech who rode with me reaffirmed that there was nothing mechanically wrong with the car. They said that it's just the noisy snow tires I have on. The tech didn't even think that I should get the rear diff oil changed as my cas has just turned 17K miles.

I'm starting to feel like an idiot now...but I will still try doing what everyone has suggested.