AUTO: Motor Medics Say Gas Additives Don’t Work

Listen to the Motor Medics every Saturday from 10AM until Noon on WTYM AM 1380 and FM 103.7.

Dear Motor Medics,
Every time fuel prices go up I start to see products on the market that claim to increase fuel mileage. Some are claiming to increase up to 4 mpg! These products range from a pill you drop in the tank at fill-up to devices installed into the air cleaner and other crazy things. If these products are so good, why are the car manufactures not installing them at the factory instead of spending millions of dollars researching how to increase fuel mileage? And if there is a “pill” you can just drop in the tank to do the same then why don’t the gas companies make a fuel that contains the pill contents in it already and market it as a fuel that gives you better mileage than the other guys?
Trent in Decorah Iowa.

Dear Trent,
While there are a few products that will help your car get a very limited increase in mileage, there are many more that are just a waste of your money. Before you buy be very diligent in your research of each product. You will find that many have not been proven to work and the ones that do may not be cost effective. You may spend more for the product than you will make up for with the limited mileage gain. As you said, if it were so good the manufacturers and fuel companies would use it to meet their goals and improve their sales. Take care, the Motor Medics.


Dear Motor Medics,
I’ve got a noise under my hood that despite several attempts at repair still persists. The vehicle is a 2004 Chevy Tahoe with the 5.3 engine and upon startup it will chirp from the engine drive belts for about 15 minutes no matter what the conditions. We have tried to repair this by switching the belt which resolved it for about a week. The next thing we tried was to replace the tensioner in hopes that the belt tension was incorrect. After the tensioner replacement, it lasted another week then was back to chirping again. Have you had this problem before and if so what kind of things have you done to stop the noise? My mechanic suggests trying a Gatorback belt. What is a Gatorback belt and do you think it may help?

Daryl in Sheldon Iowa.

Dear Daryl,
When we have belt squeaks we look very closely at all of the rotating parts to make certain there is not a problem with alignment or wear that could be the root cause of the noise. We also check for proper tension and make sure the pulleys all have good bearings. With that all done we install a new belt and if it squeaks again soon after we sometimes use the Gatorback belt which is different in design in that it has grooves on both sides of the belt which can help to eliminate noise by providing a better gripping surface area.
Take care, the Motor Medics.