Q: I have a 2011 Subaru Outback with the 2.5-liter engine. I want to know if it is harmful to downshift often without using the brakes. Recently, I've been hearing a whining that I believe is coming from the transmission. I had the 60,000-mile service done, including replacing the transmission oil. I don't remember hearing the noise before the 60,000-mile service.

A: First, I assume you are describing downshifting a manual transmission, not an automatic. Many of today's manual gearboxes are smaller and utilize smaller internal bearings. This isn't a bad thing, of course, but I've heard from a number of transmission shop owners that they see more bearing issues from these transmissions now than in the past. They, and I, recommend using the brakes to slow the vehicle rather than downshifting.

But why spoil the fun of driving a manual gearbox? Downshifting before a corner while still braking — the lost art of "heel and toe" and "double clutch" downshifting — isn't harmful and adds to the challenge of driving. Which increases situational awareness, reduces distraction and hopefully reduces "driver error" crashes.

The bottom line is this; brakes are far more efficient and far less expensive to replace than clutches and transmissions. While there's no real harm in downshifting to benefit from engine braking on occasion, such as a long downhill grade, you're better off using downshifts to prepare the vehicle for acceleration, not slowing.

It's also worth noting that manually downshifting an automatic transmission out of overdrive is often the only way to utilize engine braking due to the fact that in overdrive, the torque converter clutch and the overrun bearing/clutch in the transmission effectively disconnect the drivetrain from the engine in an effort to improve fuel economy when you are coasting.

Q: Where could I sell motor oil that I've been keeping since 1962? Some of them are straight weight — 30W, 10W, etc. Can oil that was bought in the 1960s still be any good?

A: Fun question. Like you, I still have several quart containers of Quaker State 30W and 50W from the 1970s. We used the 50W in race car engines and the 30W in manual transmissions.

Notice I said "containers," not cans. These are cardboard containers with metal tops and bottoms and show some staining on the cardboard due to seepage over the decades. I'm sure the oil is still good and have used some of it over the years to top up my lawn mowers and other small engines. The oil is not suitable for any of today's motor vehicles because of its very early API service rating — likely SC ('67/earlier), SD ('71/earlier) or SE ('79/earlier). Today's engines require an API service rating of SN, introduced in 2010.

So, where to sell? I'd suggest eBay. There are a lot of collectors out there who'd be interested in your oil. And they likely will pay more than what you bought it for 40 to 50 years ago. I found listings for my old Quaker State oil on eBay for $10 a quart.

Using them for my lawn equipment? What was I thinking?

Q: I store a 1987 Porsche from now through April. How much pressure should I put in the tires to keep them from developing a flat spot?

A: You could put the vehicle on jack stands for the winter and not worry at all. Otherwise, inflate the tires so that they won't fall below the recommended driving pressure during winter storage. If you live in a really cold climate, remember that tire pressures will drop roughly 1 pound per square inch per 10-degree fall in temperature.

Regarding potential flat spots from storage, not to worry. The materials utilized in the construction of modern tires aren't particularly sensitive to permanent flat spots. You may feel a bit of lumpiness on your first drive next spring, but the tires will quickly round themselves out after a few miles.

———

ABOUT THE WRITER

Paul Brand, author of "How to Repair Your Car," is an automotive troubleshooter, driving instructor and former race-car driver. Readers may write to him at: Star Tribune, 425 Portland Ave. S., Minneapolis, Minn., 55488 or via email at paulbrand@startribune.com. Please explain the problem in detail and include a daytime phone number. Because of the volume of mail, we cannot provide personal replies.

———

©2015 Star Tribune (Minneapolis)

Visit Star Tribune (Minneapolis) at www.startribune.com