What’s true for a Saturn not so for Camry

Dear Bob: I.H., one of your readers, asked about his 2004 Toyota Camry’s automatic transmission not shifting into third gear on a cold morning until the car had been on the highway for a couple of miles.

You recommended that he take the car back to the dealer to have this situation looked at. I respectfully suggest that your advice may be overlooking the normal operation of modern transmissions. Many newer vehicles with automatics are computer-programmed to override normal shifting operations to enable the most efficient warm-up of the transmission fluid for improved efficiency.

For example, my 2002 Saturn owner’s manual explains: “When the transaxle-fluid temperature is below 10 degrees F, the transaxle will shift from first to third gear, skipping second. The transaxle will maintain third gear until the automatic transaxle-fluid temperature rises above 10 degrees F, after which it will shift up to fourth gear if operations require.”

Thanks, Bob!

— J.M., Kansas City, Mo.

A: While what you say may be true of your Saturn, it doesn’t apply to the reader’s Camry. His owner’s manual says only that “If the engine-coolant temperature is low, the transmission will not shift into the overdrive gear even with the overdrive on.”

I.H.’s problem was not that, when cold, his vehicle wouldn’t shift into overdrive, but rather that it wouldn’t shift into third gear. That means that, until it warmed sufficiently, his car was running in second gear at highway speeds — not a good practice for any automatic transmission.

For that reason I still believe that his transmission was not shifting normally, computer-programmed or not, and that it was a good idea for him to have it investigated by the dealer.

Incidentally, for many years now I have advised readers not to shift their manual-transmission-equipped vehicles into the highest gear until the car has been running and warmed up for about 15 minutes. These higher overdrive-type gears — 5th or 6th gear in a manual transmission — don’t work very well when cold, and holding off on using them until the vehicle has warmed up will allow them to function better and last much longer.

Dear Bob: When my heater or air conditioning is off, air comes out of the vents. Is this robbing me of fuel economy?

Yours truly,

— C.G.H., Emporia, Kan.

A: It has no effect on your fuel economy, because it’s simply vent air flowing into the cab.

Your climate-control unit is probably set in the fresh-air or vent position, instead of to the recirculate setting. If you wish to stop the flow of air into the cabin, setting the unit to recirculate should take care of it.

Dear Bob: To get better gas mileage, do not use drive-through facilities. Park and walk into banks, fast-food establishments and so forth. You’ll save gas, and the exercise will do you good. Also, it’s nice to talk to a real, live person rather than a microphone.

I am 84 years old and have burned too much gas and wasted a lot of time while sitting in waiting lines.

Enjoy your intelligent advice very much — thanks.

— P.K., Butte, Mont.

A: I’ve been an advocate of parking and walking for many years now, so it’s nice to hear from an 84-year-old who is right there alongside me, doing the same thing!

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:

Rolling resistance, a major factor in fuel economy, is significantly reduced through the use of radial tires. Radials are superior to both bias and bias-belted tires when it comes to rolling resistance — that is, the amount of friction developed between the tires and the road. More friction means less mpgs, while less friction means more mpgs.

A chart in my book, “How to Get More Miles per Gallon,” graphically demonstrates the superiority of radials when it comes to rolling resistance: At 60 mph radials generate a rolling resistance that’s a full 10 percent less than that of bias-belted tires, and at the same speed radials are 15 percent better than standard-bias tires.

While not many of today’s cars come with bias or even bias-belted tires as standard equipment, some drivers are tempted to use such tires as replacements because they are less costly. Any money they save, however, is soon squandered on the extra fuel they must use to overcome the extra rolling resistance generated by these bias tires.

As if that weren’t enough, handling and safety are also compromised to some extent when a vehicle originally designed to work with radials is outfitted with any other type of tire.

So, if your vehicle came with radials as standard equipment, stay with them when replacing your tires.

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