I have a 2004 Toyota RAV4 (300,000 kilometres, all-wheel-drive, manual shift) and I am getting noise from the back end. It sounds like the differential when I accelerate to 50 km/h and gets noisier at higher speeds. I replaced the clutch last year. Could this mean the all-wheel-drive has no lubrication? Or a loose drive shaft? – Michael
Wow! There are hundreds of things that could be at fault, especially at that elevated mileage. You don't describe the sound, whether it is ticking or continual. If it is a whine that varies with speed, the likely culprit is the rear differential.
Try backing up in a safe way at some speed to see if the sound changes. The load on the internals (ring and pinion) changes with direction while that on bearings does not.
You might also be able to disconnect the drive to the rear wheels by locating the appropriate fuse or connector. Is the noise still there? To get closer to the source, put the vehicle on a hoist with someone at the wheel to operate the throttle. Avoid any excess speed, but this might help you narrow down the source of the sound.
While it is up there, check the fluid in the differential, it should be replaced by this time, at any rate. Use the opportunity to look for metal particles that would indicate serious problems.
BMW's first winter
My 2006 BMW 330 Xi will see its first winter this year as my old Subaru is being used by the children. The tires are low-profile 225/45 R17. I understand a narrow snow tire provides better traction. I am prepared to buy new (old) rims. What would you recommend for best traction? Can I put a smaller (narrower and decreased diameter) rim on the car, and thus a thicker tire better able to handle potholes and snow banks? If I do, what size tire do I get so the speedometer is fairly accurate? How small should I go with the rims? Grip and comfort are my main concerns, I will save style for the summer. Should I get rims at Canadian Tire or try a junk yard (I live in New Brunswick, not a lot of old BMWs here). Lastly, can you comment on preference for quality snow tires? – Dave
A narrower winter tire will cut through the snow and, as a side benefit, provide a better ride, albeit noisier because of the winter tread.
I would suggest a 205/55/16 winter tire. The overall diameter is within one per cent of the originals on your car and the speedometer within 0.5 km/h at 100 and likely even closer as the original tires are worn. This is a fairly common size.
The trick will be finding a 16-inch wheel to fit the car. Stick with new wheels unless you're familiar with where the old ones came from. Look for hub-centric wheels, ones where the big hole in the middle fits properly over the hub. There are some with a larger hole that depend on the lug nuts to ensure proper location but these are generally meant to fit multi vehicles and are inferior.
There is nothing wrong with Canadian Tire in this department. It has put considerable resources into becoming the go-to place for wheels and tires. It offers an impressive array from a variety of manufacturers. A quick check showed it has three in your size that I would recommend: Continental ExtremeWinterContact ($208), Dunlop SP Winter Sport 3D ($175) and Michelin X-Ice Xi3 ($188). It also has Goodyear Ultra Grip WRT at $141, but that is a step down from the Goodyear Ultra Grip Ice WRT, which you have to get from a Goodyear store.
Similarly, the Bridgestone Blizzak WS70 is a great winter tire, but only available at a Bridgestone outlet. Consumer Reports recently did an extensive winter tire test. Its results had the above-named Michelin at the top.
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