Letting Your Vehicle Warm Up

[Brandon X]

Who here lets there engines warm up before taking off?

Was talking to my mechanic buddy today and he says you don't really need to and it's just a waste of gas. I always let my engine warm up a little bit when it's been sitting for a long time, especially in the winter. What do you guys do? Seems to me it's less harsh on the engine if you let it warm up for a few minutes depending on the temperature.

 

[SunlitComet]

The only reason I would let it warm up is in very cold weather to provide warm air to help defrosting and heat inside. Kind of sucks that you would have to use the defrost with the compressor running and cold coolant. Just hop in, start-up to warm(or wait in the home while it warms)and go afterwards. A warm interior and body are safer to drive with than cold ones. Old cold starting and running issues are a thing of the past.

 

[99Yuk]

Up here, we let our vehicles warm up a bit before taking off only when it gets cold. Metal and plastic starts to get brittle in cold temps. As for today's vehicles and oil, it may not be required to let it warm up, but it doesn't hurt any.

Back in the day, I lost a 92 suzuki sidekick cam gear and cam at -32, starting and driving cold then accellerating without letting it warm up.
Didn't make it to the end of the driveway. Just cracked it.


I've also had to replace the front hood bug deflector last winter. -41 and I had to boost my truck, I just touched the hood deflector plastic to open the hood, and it shattered. Stuff gets way to brittle when cold.

Another thing that I do in the winter, (and this may be another old wifes tale), is that I back my trucks into it's overnight parking space when the truck and tranny are at operating temps at night. So that in the morning when the tranny is cold, it doesn't have to be put into reverse, just put it in drive and go. I started to do this a few years back when I got the Jimmy. Something about with the 4.3 tranny's, many are blown when put into reverse when it's very cold. Thick cold fluid puts excess pressures on a small valve or something like that? The reverse valve is smaller /thinner and more suceptable to damage then the drive valve? IDK, but it's easy to back in when the tranny is warm just to be sure.

Even if it's not required to let it warm up, can't be a problem if you do. Remote car starters are a hit every winter up here, and after I lost one engine, I'm not keen on loosing my new crate motor. I have a rule, when it's -20 or lower change longjongs from thermal to fleece, and let the trucks warm up!

BTW, thermal longjongs go on after September Labour day long weekend, and come off on May two four long weekend, about the same with letting the trucks warm up.

 

[PH99TAHOE]

Your buddy is right, unless it's below zero, there is really no need to warm up a vehicle anymore. With todays tighter tolerances, better oils, and computer engine management, warming it up is really only good for creature comforts.

With that being said if it is below zero then a couple minutes of warm up would be advisable. Notice I said a couple minutes, not 15-30 like a lot of people do. The point here is just to get some heat in the oil so it flows through all the passages and galleys freely, making sure that all parts are lubricated properly.

I get in and drive most of the time. Only if its below zero do I start my vehicle a couple minutes early. Driving nice and easy until the vehicle warms up, is always best.

 

[retorq]

Here in the AZ winter I warm it up for about 5 mins before taking off. Generally I go out and start it and then finish getting my crap ready to go in the house ... in the summer I just get in and go. It's not so much to protect the engine, although I do notice it drives a hell of alot better when not fully cold, it's to warm up the interior.

 

[foreverfalcon40]

Your engine and trannies do need to warm up! Like stated before, oil needs to warm up in order for it to function properly as in lubricting parts efficiently...

Transmission...ever cold start and feels like the tranny is shifting...makes alot of noise before it shifts into gear...its because the fluid hasn't reach opersting temp and stall converter is locking up until it reaches operating temps in order for it to shift...

do what you want...fact is fact

ff40

 

[h0tr0d]

Your engine and trannies do need to warm up! Like stated before, oil needs to warm up in order for it to function properly as in lubricting parts efficiently...

Transmission...ever cold start and feels like the tranny is shifting...makes alot of noise before it shifts into gear...its because the fluid hasn't reach opersting temp and stall converter is locking up until it reaches operating temps in order for it to shift...

do what you want...fact is fact

ff40

^--- What he said x2!

I don't even live in a cold climate down here in Texas and I still let my truck warm up some. I've read somewhere that at around 130 degrees engine temp is optimal before revving over 3000rpm to avoid premature wear. I run 10w30 year round here, so if you're running 0w or 5w that does change things.

Also, on many trucks if the engine temp is less than 140 the ecu enters a closed loop mode and is just dumping all the fuel it can into the cyliders. At idle, it's not that big of a deal, but when driving, you're going to get some seriously bad gas mileage.

Edit: I should also state that I have personally spun a bearing in a latemodel '02 truck running 5w oil by revving the engine near redline without letting the oil warm up on a 30 degree night.

 

[sumo]

i start mine 10 minutes before i leave in the moring for winter. I agree with falcon, Plus the warmth of your bodies and Breath fog the windows right up, so you end up waiting anyways for the defroster to work. In the summer, i just start and go.

 

[Brandon X]

Guess ill let it warm up for a few minutes then. Better safe that sorry.

 

[moviewithnotitle]

I have had a personal standing rule since I started driving.
>40degrees, just get in and go.
<40 degrees, warm up truck for 5-10min while getting crap together for work.
<20 degrees, start truck, go back inside, take shower and dress, get on my way.
So far this has worked out really well, and I am always comfy when I start my drive to work or wherever. I can't always do this, but I do it as often as possible and personally feel it makes a difference.

I also ALWAYS warm up my boat before going out. 10min minimum. This lets me know if the raw-water intake picked something up and is clogged. Better to still be at the dock when you find out.