True or false: You should always warm your car up before driving on a cold day. The answer is false. Although the majority of the driving population may consider this to be true, it can actually cause damage to vehicles if done continuously. There are a number of automotive beliefs drivers encounter on a daily basis that may or may not be accurate. To shed some light on this topic, the service specialists at Chrysler, Jeep and Dodge provide their car-care expertise to confirm and debunk eight common automotive beliefs.
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Belief: Do not blast your vehicle’s air conditioner when sitting in traffic or while driving at more than 60 miles per hour.
Reality: False. Vehicle heating, ventilation and air conditioning (HVAC) systems are engineered and tested to operate in even the most severe types of driving environments. The air conditioner has cooling fans and condensers that allow it to operate under these conditions.
Belief: It is possible to check your tire tread with a penny.
Reality: True. Although the service specialists at Chrysler, Jeep and Dodge prefer you use a proper tire gauge to check tires, it is possible to check tire tread with the use of a penny. Simply pinch a penny between your thumb and forefinger so Lincoln’s head and “In God We Trust” are showing. Insert the penny into a tire tread groove. If the tire covers any part of Lincoln’s head, then your tires should have a safe amount of tread. If you can see Lincoln’s head in its entirety or any parts of “In God We Trust” are showing, it is time to invest in a new tire. Be sure to check all tires and in different locations on each tire because the amount of wear can vary from tire to tire and from inner tread to outer tread.
Belief: If you still have fuel in your gas tank when you refill it, use the same grade of fuel that is currently in the tank.
Reality: False. As long as you use unleaded brands of gasoline, it will not harm your vehicle if you mix different grades of fuel.
Belief: Avoid keeping your vehicle at a constant speed during the first 500 miles of a vehicle’s life.
Reality: Maybe. Most new vehicles no longer require drivers to vary their speeds during the first 500 miles of a vehicle’s life, known as the “break-in period.” If your vehicle does require the “break-in period,” then you should avoid keeping a constant speed during this time. Even varying your speed by several miles per hour should do the trick (of course, within legal limits).
Belief: Your vehicle’s engine should be “warmed up” before driving in cold weather.
Reality: False. Warming your engine up, or idling, is not the best route to take. In fact, excessive idling can be damaging to your vehicle. You should, instead, drive the vehicle to get the engine warm during the cold weather.
Belief: Premium gasoline is best for your vehicle.
Reality: Maybe. It depends on the type of vehicle you drive. Most cars are built to run on regular-grade fuel, so using premium fuel will not improve the car’s performance. In fact, using premium fuel in a vehicle that was not designed for it can harm the vehicle’s performance and fuel efficiency. Check your owner’s manual for recommended fuel grade.
Belief: For city dwellers dealing with narrow streets, do not park with two wheels on the curb, as it will destroy the vehicle’s alignment.
Reality: True, if done continuously. The Chrysler, Jeep and Dodge service specialists say that repeatedly parking a car with one side’s wheels up on a curb to provide more space for passing cars can cause excessive wear or stress to tie rods and suspension bushings, and could create alignment issues.
Belief: If the steering wheel shakes when you drive, there is something wrong with your brakes.
Reality: Maybe. If the wheel shakes as you depress the brake pedal, it may mean your brake rotors are unbalanced. If the wheel shakes as you drive, it may be the result of a wheel balance or steering-related issue.
##RVT978
Quickest way to warm up your engine is to drive it.- Smokey Yunick
Oil pressure….10psi for every 1000rpm is sufficient. Also Smokey Yunick.
Once you have oil pressure, your engine is lubricated.
Oops! I just read in “True or false? Popular vehicle myths explained,” Belief: Your vehicle’s engine should be “warmed up” before driving in cold weather.
Reality: False. Warming your engine up, or idling, is not the best route to take. In fact, excessive idling can be damaging to your vehicle. You should, instead, drive the vehicle to get the engine warm during the cold weather. I’ve been lead to believe engine idling for a long time is not harmful, and one of the features of hooking up inverters to car batteries?
I will warm my car up with the engine idling so I don’t have to drive blind with a frosty windshield and freeze for the 10 miles. In a perfect world, all vehicles reside in heated garages in cold climates.
My F150 hybrid with the powerboost engine in the owners manual says not to tow with till you put 1000 miles on the truck. I’m not sure excess idling will harm the vehicles. If it was true they wouldn’t have remote starts. I also think there was a previous article by Mike Sokol with the car generator that data indicated letting the vehicle run wouldn’t damage the engine. My F150 has an on board generator that I can leave the truck running. Older vehicles excess idling may not be acceptable. Had a 87 corvette you couldn’t let the a/c run in traffic sitting still would raise the temperature.
I know most cars don’t come with them and many people do not need them but the almighty block heater is still king. No LONG warm up needed and heat coming almost instantly and your car engine and transmission will love you for it. I just wish they came on all cars delivered in northern states. They used to be easy to install but with modern engine not always easy to do yourself now with engines crammed in so tight. Coming on new car from factory they are usually very cheap not so cheap to have dealer add later. God I miss having them on my cars. Now if I could only have a long enough extension cord to run all the way to work 🙂
I installed a couple when stationed in Alaska. Pretty easy on the two vehicles I owned at the time, not sure I would try on today’s vehicles. But they were a life saver for sure. Engine block heater, trans pan heater, battery blanket heater…umbilical cords out the grill were the norm in interior Alaska. My last year in Fairbanks area , we hit -60° , I’m at work, started my truck to get some warmth going, when I went to get out I accidentally grabbed steering wheel and my steering pump exploded it was so cold. Set at work for a week due to all the vehicles broken down due to the cold, but hey they fixed it under warranty.
Forgot the interior heater
“Popular vehicle myths explained”. Huh?? I didn’t see any explanation on how “excessive idling can be damaging to your vehicle.” What kind of damage? How does it damage the engine? Really bad writing (or editing) on this article. I would like to know more, please.
Idling the engine doesn’t get up to operating temperature, condensation forms and mixes with the oil causing acidic conditions. The engine must reach operating temperature in order to evaporate the condensation. If you own a motorcycle or another type of vehicle that gets stored for the winter don’t start it every month to circulate the fluids, just put a battery maintainer on it and let it sit.
I see I’m not the only one disagreeing with not idling your car to warm it up. I would add that for older cars it may be a necessity. I drive a 2002 Saturn SL1 and if I don’t warm it up until the temp gauge is a quarter of the way up from dead cold it has issues shifting properly. This is only necessary for me in the winter in Western Oregon. I used to be able to just get the needle above dead cold but the older the car gets, the more “warm” it wants to be before I start driving.
Maybe you should change the transmission fluid, but don’t flush it, that’ll cause more problems.
Thank you, I’ll look into that!
Should have been a disclaimer *
Does NOT apply to diesels!
Not only does the Ram manual states to warm up it also states to cool down for up to 10-15 minutes . Oddly Ram currently is having problems with diesels and claiming owners aren’t waiting for warm up causing engine failure.
I have a 2014 ram 2500 and mine does not state that amount of idling, a minute or 2 starting and depending on city or highway speeds up to maybe 3-4 minutes before shutdown. States to just take it easy for the first few miles until warm, ie no sudden acceleration, rabbit starts etc. 15 minutes is overkill especially when they all come with an auto shutdown after so many minutes 10-15 or so.
I always warm mine up. 2014 RAM CTD. Never heard of “auto shutdown”. At least mine doesn’t do that.
What a stated was in my owners manual, 2016 . The owners manual I speak of is the one you need to request, it’s over a 1000 pages. Marion Blair has a YouTube on this subject, He has a 2014 ctd. I recommend his CTD videos
Mercedes Sprinters do not like to be idled.
The reason is: when idling, the engine use more DEF fluid. I don’t know if that pertains to other diesel engines (I would expect it does) but
I do know it pertains to the Mercedes diesel engine. It’s a waste of DEF fluid to idle for long periods.
When it’s 40 below outside we warm up our vehicle, defrost and or scrape windows. Never mind the tires are a little flat or square. Haven’t plugged our vehicle in years because we are usually in Florida in the winter but not this year, staying safe at home in Canada and trying to keep warm. Have a safe and happy holiday to all.
If you get shaking and vibration when applying the brakes it would be a whole lot more likely that 1 or more brake rotors have warped. A brake rotor “out of balance” would be extremely unlikely.
And they’re likely warped only because the wheel nuts were improperly torqued. Try loosening all the lug nuts and re-torquing properly.
most of the time when they are warped they are done. many brakes rotors today are made fairly thin, they do a great job most of the time but because they are made as light as possible to save weight they don’t always stand up to hard braking at high speed well.
Glazed pads from hard high speed freeway stops don’t help much either.
Once they are warped due to improper torquing, they can’t be fixed, only replaced.
Our Honda owner’s manual has specific instructions on how to ready our car’s transmission before towing. That requires idling 4-5 minutes at least once daily when we are on the move. We have always briefly idled our vehicles before moving, especially in cold weather, and have had good results.
Briefly idling doesn’t harm the engine, extended idling will as the oil pressure is low, the water temperature doesn’t get up high enough to eliminate condensation, and acids that build up in the crankcase. This also applies to a new type of emergency generator that connects to your car battery to supply electricity to your home. Personally I would rather spend several hundred dollars on a portable generator than ruin a several thousand dollar engine, but they don’t tell you that idling your engine several hours will damage it.
As an aircraft mechanic, I disagree with the “experts” on not letting your car warm up before driving it in extreme cold conditions. Would you jump out of bed and immediately run a mile! Of course not! A car that’s been sitting in cold conditions (depending on length of time) has had the oil drain from the upper parts of the engine to the oil pan. Different metals have contracted at different rates therefore internal clearances have changed. I start all of my cars in my garage. After maybe 10 seconds I back onto my driveway. I let my cars idle for maybe 1 minute to get the oil circulating and the engine to start to warm up. I back out of my driveway and drive slowly down the street. Once I come to a “main street” with traffic I’m ready to drive at normal speed. I’ve never had a problem using this process, and I’ve never had a car that burns oil or leaks seals. I do the same process year round, which includes summer heat.
agreed with 100%. it depends on what people consider “cold” and what “length” of warm up you talk about. Here in MN things often get well below 0 F degrees. When you start talking -10 or -20 below metal can become more brittle. I have seen severe metal fatigue snap metal like brittle sticks in the dead extreme cold(-20F or more) of winter. When it’s below 0 F I often wait a minute or 2 to let things warm just a bit and also don’t drive hard or fast for the first few blocks as well. No need on most cars for a 10 or 20 minute warm up tho. Diesel engines do need a few more minutes tho.
Your type of idling is proper, it’s the idling that some people think is necessary where they start the engine then go back inside for another cup of coffee and donut for another 20 minutes. Even truck drivers who start their engines after being off several hours will start them and when air pressure has built up for the air brakes will slowly start driving, an engine will warm up sooner under a light load than idling.
And for shake/vibration my drive shaft was just off enough at 55-60 to cause the effect. Brake rotors and all else were fine.
If you feel the vibration in your butt, it is driveline vibration, if you feel it in the steering wheel, it is frontend vibration.
Also have warmed up the Ram sitting idle in cold weather. What’s the point then of remote. No mechanical issues for years and the Dodge/Ram dealers has never stated not to so what’s the conspiracy theory?
Diesels are different, my Chevy 2500 Duramax manual actually says to warm it up for 5 minutes in cold weather.
Especially when towing or loaded.
You beat me to it Crowman…I NEVER put any load on my Cummins until it’s warmed up to at LEAST 120 deg on the gauge…
5 minutes is a lot different than 20-25 minutes I’ve seen some diesel owners do. I have seen many who start their engines before breaking camp and idle the entire time they spend breaking camp. Totally unnecessary!
Remote start is a convenience that also is a marketing ploy as the sooner your engine wears out the sooner you’ll buy a new vehicle. They win either way, you get into a warm vehicle, happy customer, engine wears, happy dealer.
Regarding idling, “ In fact, excessive idling can be damaging to your vehicle.” This answer contradicts assertions by the maker of CarGenerator. Of course, they have a vested interest in stating long stretches of idling is fine. But I am curious for more in depth analysis.
They are selling their product do you really expect them to tell you their generator will harm your engine? I have written this company several times about their false advertising with no response. I am surprised rvtravel.com accepts their advertising based on this.
WRT “warming up”. What is considered excessive idling and exactly what engine damage can happen? I live in Canada and in the winter I have always let my vehicle warm up for a couple of minutes before driving and have never had a problem. In fact, I have had more issues with vehicles if I start and drive right away in freezing weather. Transmissions don’t want to shift properly et cetera.
Most modern cars (and big diesel engine RV’s) don’t warm up when they idle. If you can increase to fast idle that helps. I had a Land Rover Discovery diesel that had a factory installed auxiliary heater to warm up the coolant when on idle so it could pass emission tests. Having said all of that, my experience is with “normal” winter low temps but not what you get in Canada !
Big diesel engines certainly do warm up when idling from cold, try touching one before and after! (or watch the temperature gauge) Diesels will cool down when idling from full running temperature.
Any engine will feel hot to the touch over 120 degrees but it’s not warm by engine standards. Normal operating temperature is between 180-195 degrees.
According to my 2500 Ram it does. The instrument panel has coolant and oil temperature gauges and you can see it warm up to operating temperatures.