Warming up your car


#1

I have always warmed up my cars . It is my understanding that when you warm up the car everthing expands causing the motor to “seal” all the way . The seals dont seal tight until it is warm . So if you put an engine under load before it is warm you risk blowiing the seals .


#2

Not true. The car’s ready to be driven, albeit gently, as soon as it’s started. Drive conservatively until you reach operating temperature. If it’s really cold (like, -20F and below) I’ll let it warm up for a while before I get in, but that’s more for my comfort than the car’s.


#3

I don’t warm up my car, but prefer to start driving mildly until the engine is warmed up, warming up the rest of the drivetrain as well. The seals will seal no matter the temperature. I think your fears are misplaced. All of my cars have 250,000 or more miles, and I haven’t had a lot of seals blow out on me.


#4

This might have had a grain of truth 50 years ago but today that thought has no merit. You need to start and let your car warm up only for as long as safety requires–you need enough heat for the defroster to keep the windows clear.

True, if it is really cold your first several miles should be easy driving to let the non-engine related fluids warm up a little, but unless your front door opens up to a freeway that shouldn’t be an issue.


#5

I always let mine warm up until the rpm drops to around 1000. I just want to make sure the oil is flowing before I get going. If it was really cold, I would probably let it go a few minutes. I would just want the oil to warm up and thin out a little.


#6

Not true. Sometimes I let the engine idle while scraping ALL the glass clear of ice, but on some of the coldest days, ice and frost on the glass is not a problem because the air is so dry. On those days, I start the engine and within one minute, I’m about a half a mile down the road going 45 MPH.

I haven’t blown a seal in 267k miles on the Saturn, 181k on the truck or 184k on the Honda, or 180k on the previously owned Colt. In fact only one car I’ve owned over the last 49 years has ever blown a seal and that was a Toyota with near 300k at the time, that particular Toyota engine (A series) had a history of blowing the crankshaft seals so it was normal to replace it when replacing the timing belt. I did not know that but got lucky that mine lasted so long.


#7

All good replies.

And the opposite is equally true - which is if you prefer to get into a warm car and choose to let it warmup for a long time, you will never notice any shortened engine life from it.
(Perhaps 313K miles vs 315K miles).


#8

Its all about getting the oil warmed up. That’s why you have different numbers in oils like 10w30 or 5w30. Engine needs lubrication to run, and cold oil does not provide good lubrication.


#9

I’m not sure how sitting there with the engine running and the oil not being warm is any better than driving with the oil not being warm. Back when I drove my parents’ 61 Chevy Belair the only reason I had to warm it up was because it would stall if I tried to drive it when it was cold.


#10

That’s why they make multi-weight oil. It lubricates better cold than straight weight. Cold oil with the proper weight will provide adequate lubrication as the engine warms up.


#11

You can do a simple test with cooking oil. When you first pour the oil in a frying pan and stir it, it is harder to stir. Once warmed up it becomes easier to stir. Well you cannot tell much difference in the summer. But in the winter you will notice the cooking oil becomes like butter. You have to warm it up a lot longer. So when you start the car, this thick butter will not lubricate well and cause metal to metal contact or wear. That’s why you have multi-weight oil. The lower the number like 0w or 5w the thinner it will be when cold. You cannot put 15w because it will be thick for winter starts. Once the oil gets warmed up it does not matter if its winter or summer. Same like in a fry pan, does not matter if its summer or winter once the oil gets hot, its ready to cook. Well another test is if you stir a spoon in 20w50 and then spin the spoon in 10w30. You will notice that the spoon spins faster and easier in 10w30 rather than in 20w50. So basically an engine will spin faster in a lighter oil than a heavier oil. So therefore a lighter oil will give more fuel economy. That’s the theory for todays 0w20 car oils.


#12

It’s an old wives tale. I might wait a minute or so if it’s below zero outside but other than that…just start and go. I wouldn’t drive very fast at first or do burnouts but otherwise…you are good to go.


#13

On the other hand, if you live in upstate Minnesota where it reached -47F ambient recently, you have our permission to warm it up before getting in. Your heiny will thank you.

The engine just needs to run enough to get the oil circulated, and that just takes a few moments. Then you’ll want to go easy until it reaches full temp.


#14

Aside from extreme cold temps (where I’d use a block heater) there is no, zero, nada need to warm up.


#15

Naw. Anymore I start the car without my belt on. Let it idle for a few seconds while I put my belt on, etc., then drive it gently for a mile or so until the heat gauge registers. If it is really really cold and the car is outside like 10 to 20 below, I’ll let it run a little first and am super careful of the transmission at those low temps.


#16

Safety first! You need to be able to see out the window, whether the vehicle needs it or not. I don’t care how dry the outside air is…you’re exhaling warm, wet air at a sub-freezing hunk of glass. either use SCBA (with rebreather), hold your breath for the first 3 minutes…or let the defrost air get tepid.

For those who see -20F on occasion…can very cold glass simply get “too brittle” to accomodate whatever stresses driving throws at it?


#17

@meanjoe75fan, -20F is a recent extreme, but the glass works just like normal. it just takes a little longer for the car interior to be warm and a little longer for the electric rear defrost to work. nothing is too cold or brittle for the stresses of regular driving. now if you have an imperfection already in the glass, this may cause it to expand and spider crack


#18

If the windows are clear, just 15 to 20 seconds is enough to start the oil circulating to the valves if it is the right oil or you have a block heater.

Then gently drive off; the seal myth is just that, a hangover from 50+ years ago.


#19

Warming up the engine only warms up …the engine.
Still cold…and frozen ;
Transmission
differentials
wheel bearings
steering
etc.

Gently getting under way in short order is the only way to warm these other fluids, oils, and greases.


#20

I used to warm up my cars and drive them gently until they warmed up, now I usually drive a prius which got tainted after my wife hit a skunk in it. Its going back at the end of the lease so I just drive it and don’t worry. I started it up on a recent -15 degree morning and took off. No damage done. I no longer heat it up, just get in and go.

I actually think its hard on head gaskets if the car heats up really fast due to the quick expansion of the metals