Michael952

actually at idle not much fuel is being wasted. I'd rather get in a half warm car then save the 10 cents in fuel lol. I personally think it's best to let it run for a minute or so to get everything flowing in the cold weather but if it's warm outside then I just fire it up and drive normally. That being said I have beat mine pretty good. She sees the rev limiter every time I wheel it and runs even better then the day I bought it.

SHELBYGT NSM

Doubt 30 seconds or a mintue will do,

XJriot

Sure it will.

As long as the oil is flowing and you're not running 15w40 in those temps you'll be fine.

Your engine isnt the only thing that needs to be warmed up. Driving for a minute or two with the heat off will warm your car up quicker than sitting at idle and wasting gas.

salad

Completely agree. The article, while providing a decent rationale, I don't think is written about the actual cold. Maybe someone in North Carolina that sees snow a week a year. Sure wait a minute when it's around freezing but if you wait "10-30" seconds before driving off in -30, that **** just isn't happening.

Why? Engine oil simply doesn't provide enough protection below a certain temperature that you can safely apply a load. Winter ratings are for pumpability and cold starts, the SAE makes no claims as to performance when it's -30 out.

And of course, as mentioned, engine oil isn't the only thing being heated up. If on a day like today where it's -16 out there, I have my block heater plugged in, so I start and go, I'm not going to have any steering, my power steering pump is going to be howling and any pressure with -16 degree fluid is going to put undue stress on it, and my transmission fluid is going to be so thick that I won't be able to drive "lightly"! Not to mention without ambient heat from the exhaust my clutch takes two feet to depress.

A reasonable guideline, if you don't have a block heater, is to let it warm up to about 40° (100°F) before pulling it off. This is where your temp gauge starts in the dash and the lower end performance rating for most automotive fluids. (eg. API motor oils)

dogger15

That's how Denver was a couple weeks ago.

SHELBYGT NSM

I feel ya buddy, the wind was blowing 25 to 35 mph, my antifreeze froze in my radiator, it was horrible.

SHELBYGT NSM

Do you prefer a toboggan or a ski mask for when you stick your head out the driver door window waiting for your defroster to clear your windshield?

XJriot

Neither. The only window that fogs over in mine is the driver side window. If you don't have air blowing on the front window and aren't breathing like a cave man then you should be fine. That's where the 'turn off your heat for a couple minutes' comes in to play. Once the Jeep is warmed up you can blast the heat and not have to worry about fogging up the front window.

But to each their own. I'm not a millionaire and I don't have money to just give away so im all about saving money where I can.

dogger15

You know its cold out when your dog doesn't want to go outside to take a dump.


My family lives in Upper Michigan and it was -40-50 out with wind. only -15 without.

wcshale

I think some folks are missing the point, warming your motor is not getting it hot enough to operate your heater. Its taking that cold metal that your engine is made of and getting it to a temp where it fits together the way it was built. Example.. we freeze bushings so that we can put them in a hole that's real close tolerances, when they thaw they wont come out. Your motor was machined to fit together and I bet it wasn't built in a shop at below freezing temps.

wcshale

Salad is right viscosity does change with temp. Put oil in a syringe and squirt it, put same oil in same syringe, freeze it and try again......... see?

4OHI6

I agree it has been cold and the coldest in 18 years here in Richmond, but wind has nothing to do with antifreeze freezing.

4OHI6

So are we talking about what is best for the Jeep and the mechanical system or the Driver? In normal/average or extreme conditions? Just trying to focus the conversation.

salad

Jeep, he was being facetious.

It would help mentioning what sort of conditions, however, as it DOES vary.

XJriot

It is quite hot inside of the engine once combustion starts happening. It does not take long for the pistons to start warming up.

We also froze parts in the shop I used to work at. We used liquid nitrogen to drop a part roughly 0.002" so it fit in a machine bore. If your temps are on par with the temperature of liquid nitrogen then I think you have a bigger issue and should consider moving away from your -320 degreeish environment.

For future reference you can expect the common metal to change size something like 0.000006" per degree of change. It is some ridiculous tiny amount. Ill have to look in my old text book for the actual number.