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Our technicians can diagnose your car trouble.



Have your Cooling System inspected to prepare for the summer heat.



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DeMark Auto Service Offers Auto Repair Services You Can Count On!

DeMark Auto Service is the automotive expert in Caldwell, ID 83605. Since, 1959 we've provided the Caldwell area with reliable, affordable automotive maintenance and repair services including 4x4 Services, Alignment, Brakes, Car & Truck Care, Domestic Cars & Trucks, Electric and Hybrid Vehicle , Electrical Services, Electronic Services, Engine & Transmission, Engine Maintenance, General Services, Heating and Cooling Services, Import Cars & Trucks, Inspections and Emissions, Miscellaneous Services, Quick Lube Services, Tires, Towing, Transmission Services and Undercar Services.

We have experience servicing all makes and models of domestic and import vehicles, and we're honored to keep vehicles throughout the Caldwell area reliable and well-maintained. Our skillful mechanics will take great care of your vehicle too, quickly diagnosing any problems and offering cost-effective solutions to get you back on the road.

Call DeMark Auto Service today at 208-459-3468! You can also send us an email. Either way, we're looking forward to providing you with reliable automotive service!


    Areas We Serve

    Vehicle Tips

    According to recent studies, 5 percent of all motor vehicle fatalities are clearly caused by automobile maintenance neglect.

    The cooling system should be completely flushed and refilled about every 24 months. The level, condition, and concentration of coolant should be checked. (A 50/50 mix of anti-freeze and water is usually recommended.)

    Never remove the radiator cap until the engine has thoroughly cooled. The tightness and condition of drive belts, clamps and hoses should be checked by a pro.

    Change your oil and oil filter as specified in your manual, or more often (every 3,000 miles) if you make frequent short jaunts, extended trips with lots of luggage or tow a trailer.

    Replace other filters (air, fuel, PCV, etc.) as recommended, or more often in dusty conditions. Get engine drivability problems (hard stops, rough idling, stalling, diminished power, etc.) corrected at a good shop.

    A dirty windshield causes eye fatigue and can pose a safety hazard. Replace worn blades and get plenty of windshield washer solvent.

    Have your tires rotated about every 5,000 miles. Check tire pressures once a month; let the tires cool down first. Don't forget your spare and be sure your jack is in good condition.

    Check your owner's manual to find out what fuel octane rating your car's engine needs then buy it.

    Keep your tires inflated to the proper levels. Under-inflated tires make it harder for your car to move down the road, which means your engine uses more fuel to maintain speed.

    Lighten the load. Heavier vehicles use more fuel, so clean out unnecessary weight in the passenger compartment or trunk before you hit the road.

    Use the A/C sparingly. The air conditioner puts extra load on the engine forcing more fuel to be used.

    Keep your windows closed. Wide-open windows, especially at highway speeds, increase aerodynamic drag and the result is up to a 10% decrease in fuel economy.

    Avoid long idling. If you anticipate being stopped for more than one minute, shut off the car. Contrary to popular belief, restarting the car uses less fuel than letting it idle.

    Stay within posted speed limits. The faster you drive, the more fuel you use. For example, driving at 65 miles per hour (mph) rather than 55 mph, increases fuel consumption by 20 percent.

    Use cruise control. Using cruise control on highway trips can help you maintain a constant speed and, in most cases, reduce your fuel consumption.

    Keep your engine tuned. A fouled spark plug or plugged/restricted fuel injector can reduce fuel efficiency as much as 30 percent.

    Inspect the engine's belts regularly. Look for cracks or missing sections or segments. Worn belts will affect the engine performance.

    Have the fuel filter changed every 10,000 miles to prevent rust, dirt and other impurities from entering the fuel system.

    Change the transmission fluid and filter every 15,000 to 18,000 miles. This will protect the precision-crafted components of the transmission/transaxle.

    Inspect the suspension system regularly. This will extend the life of the vehicle's tires.

    What Our Customers Are Saying

    -Stoney W.

    BIG Shout Out and THANK YOU for getting a BIG JOB done on my Jeep! We also took our brand new Ford F150 in for service and TLC before we hit the road on our big summer travels..They had them both done and ready in no time flat! Best Rates, Best Service, Best People! Thanks DeMark Auto!!! We recommend you to all of our family and friends- and Always will!

    -Curtis C.

    I have used De Mark Auto almost exclusively for 9 years, after being referred by a friend who also uses them exclusively. They have always been friendly and fair. I've referred them to several other friends.

    -Kara C.

    We've been taking our cars here for years and have always been pleased with the work and the dollar amount for the work. The DeMark's are honest and the only time there was a random issue after they worked on our car, they immediately fixed it. We'll be taking our cars to DeMark Auto for years to come.

    -Stephen W.

    Trustworthy, honest, excellent work. Prices are fair and they do not push anything on you that you do not need.

    -Ken D.

    Excellent auto repair at a fair price. Professional all the way.

    -Homer S.

    I went in with what I believed to be a major problem, but left with a quick and inexpensive fix. Honesty like that is priceless.

    -Galandrios M.

    Fair pricing, on time and great customer service!

    -Kathy H.

    Always great service for us!


    Our check engine light was on and another mechanic quoted me $850 to have the transmission solenoid replaced and the transmission flushed. Demark did all the work and charged us $650. Were very quick and have just won a customer for life!

    -Scott W.

    Good work for a fair price. Not always trying to upsell you on things you don't need like some other service places nearby.

    -Conchi G.

    The guys here are quick, courteous, and honest. We have been taking our vehicles here for many years.

    -Shannon S.

    Quick and easy. They get your car done fast and right the first time.

    -Jennifer M.

    We have taken in 2 of our vehicles to De Mark and had great success. They have been great to work with.
    ASE (Automotive Service Excellence)
    ASE Master Technician
    Bosch Service
    Parts Plus
    Car Care Aware