Avoid storing vehicles in ‘rust zone’

Dear Bob: My auto mechanic tells me that it is his opinion that an unheated garage is the worst thing for a car. He states that, when a car is left outdoors, the air circulates around and under the vehicle and less rust is formed, because there is less opportunity for salt and moisture to collect under the vehicle and do damage.

My commute to work is about 4 miles, which does not give the vehicle time to warm up and perhaps allow for additional circulation.

My last car, a 1987 Olds that I garaged religiously, had extensive body rust. I recently had the rotors and pads replaced on my current Toyota at 67,000 miles, and the rotors looked rusty and worn. However, could this be normal? No body rust on the Toyota, but I do wonder if garaging my car contributes to parts rust and body rust.

I’d very much appreciate your opinion.

— L.C., Methuen, Mass.

A: It’s not so much the moving air that’s at issue as it is the actual air temperature. On a cold day the temperature inside an unheated garage may be between 32 degrees F and 40 degrees F. This is the perfect climate for initiating oxidation, the chemical process that produces rust.

If the car were left outside, where the temperature most likely would be below freezing, no chemical reaction would take place and the rusting process would be put on hold. Similarly, in temperatures warmer than 40 degrees F, the salt solution begins to evaporate — and the salt can do no harm if it isn’t in solution.

You should avoid storing your car for extended periods anywhere with temperatures in the rust zone. And, oh yes, buy a thermometer and put it inside your garage, so you can monitor the temperatures.

Dear Bob: I have a 1984 Chevy van with a 5.7-liter 350 engine. When I bought it, it had 110,000 miles. I always treat my vehicles well and always change the engine oil every 3,000 miles and the transmission fluid every 30,000 miles or so. The odometer now reads 234,000 miles.

The other day I went to a transmission expert to have my transmission fluid and filter changed, and the shop said not to do so because, if I did, something might happen to the transmission, like blown seals and other sorts of things.

How true is this? It’s the first time I’ve ever heard this, and I’m very puzzled by it.

Read you regularly.

— J.M., Middletown, N.Y.

A: If your transmission had never had its fluid changed, yes, after 234,000 miles fresh fluid more than likely would cause the seals to leak. The fresh additives would attack and loosen the deposits around the seals, the so-called false seals, that had actually kept the transmission from leaking fluid for so long.

In your case, however, with you having changed the fluid on a regular basis, there is no need to be concerned about false seals. I would continue to change the fluid on the schedule — every 30,000 miles or so — that has blessed you with 124,000 transmission-trouble-free miles.

Dear Bob: As an expanded answer to your recent reply to a reader concerning proper tire pressure, I offer the following:

The reader’s pickup is designed to operate under varying load conditions. The tire pressure for normal use, with the truck unloaded, is the manufacturer’s recommendation of 35 psi. The maximum tire pressure printed on the sidewall of the truck’s tires is listed at 44 psi. This is a guide to be used when operating with the truck loaded.

The reader should be advised to increase tire pressure when carrying a load, either to the vehicle manufacturer’s pressure rating for loaded conditions or to that recommended by the Rubber Manufacturers Association for that particular tire and load.

The higher the air pressure, the greater the load capacity, as long as you are within the tire manufacturer’s specified load range.

Thanks.

— A.E., via e-mail

A: I couldn’t agree more — you said it all!

AMERICAN DRIVERS FIGHT BACK

Here’s a tip that will help you get better gas mileage while fighting terrorism and cutting our nation’s dependence on Mideastern oil:

Don’t try to clean a paper-element air filter. This procedure can do more harm than good. True, dirt and dust can be removed by blowing out the filter with an air hose or pounding it on the ground — but, once the filter is replaced and the car is started, the engine vacuum will suck previously lodged but now loosened particles into the engine, which can cause premature wear and decreased fuel economy.

If you think the air filter looks dusty, dirty or stained, replace it. Filters are relatively inexpensive and are cheap insurance against engine wear, and a new one will always enhance gas mileage.

In other words, where your filter is concerned, you have only two choices: leave it alone or put in a new one. Don’t try to clean the old one.