Do You Let Your Ss Warm Up At Cold Start Ups Before Driving?

[Berry]

Last winter, a co-worker of mine asked me what I get for gas mileage. "In the summer time I get about 14.5 - 15 mpg, and in the winter time, it goes down to about 13.5 to 14 mpg." "Why is that?" "Maybe because I let her warm up for at least 5 minutes before I drive her." "With todays close clearence engines, you don't need to let it warm up for that long. Thats the old school way of thinking. You only need to let it warm up for about 1 to 2 minutes. Anything more than that is just waisting gas." Is this good advice, or should I let her warm up for 5 minutes before driving her?

As the temp starts to get colder up here in the northeast, I figured I'd throw this out there and see what I get for responses.

[benjaminh2]

regardless what anyone says, old/new school, anytime an engine experiences a "cold start" it should run for at least 5 min. especially here in the noreast. i let mine idle till the inherant piston noise goes away, on a cold morning ( below 20 degrees) it takes at least 5 min.. keep in mind too that most engine wear occurs during cold start. running synthetic motor oil helps out too with extreme differences in heat. IMO

 

edit: plus who wants to get into a cold truck? lol

Edited September 17, 2008 by gmperformanceguy (see edit history)

[eddieo818]

Well i live in cali so for me its a bit different weather wise... but i always warm up everytime i start her up i usally wait for her to idle nice and smooth takes about a minute or two max..

[Rausche]

First thing in the morning I always give about 5 minutes of warm-up time. Throughout the day if the motor is running at consistent intervals (never sitting for more than say, 3 hours), I'm less cautious and usually will not wait more than 1 minute.

 

My thought process is that most oil leakdown / settling occurs overnight (a period of 8-12 hours). I think that after the motor oil is and hot and not settled in the pan, less damage will occur even if some cooldown has taken place.

[Fireman31]

Absolutely warm it up, at least 30 seconds minimum. On a cold start in the warmer months I give her around 2-3 minutes to warm up, colder months I give her 4-5 minutes.....sometimes longer. My truck rarely goes more than 12-15 hours without being started.

 

When i'm responding to the FD during the night(time of year does not matter), the first thing I do is start the truck with the remote starter. By the time I get dressed and put my shoes on, 1-1/2 to 2 minutes goes by which gives the truck just enough warm up time to drive it.

[misterp]

 

5-minute warmups are rediculous - 30 seconds is appropriate when outside temps are above freezing; between 0 and 32 degrees I might add *maybe* another 30-60 seconds. Street pistons expand to size pretty quickly, and modern oils work at 40+ so you only need to warm the engine up enough to get the oil temp to 40 and at that point you can drive the vehicle under 3500-RPM using no more than 1/2-throttle until the engine and transmission oil temps have normalized (this takes 10-minutes of driving). Under normal environments there is no benefit for the engine to have a 5-minute idle period; yes in arctic zones the oil will need more time to come to working temp but this is only 1-2 minutes at most to get the oil to above 40-degrees and then you can drive the vehicle just like in the lower-48 winter conditions.

 

BTW - same rule applies to new engine breakin, 30-second warm-up then put it in gear and take a 500-mile drive at no more than 3500-rpm and no more than 1/2-throttle; our 355's always made a good 10+ HP more than our competitors at Stockton 99 because of ringseal, our routine was to install the motor in a '66 longbed truck full of firewood and drive to the top of Sonora Pass (8500-ft) then back down and then through Yosemite park & back, then drain fluids and install the engine in the Nova for qualifying...

 

I agree with GMPerformanceGuy, the engine is not really warmed-up and ready to make full power until all the parts inside have reached thermal balance, especially lubricating fluids. So the point here is not the length of idle period but rather that you don't stomp your foot into it until it's ready for work. I wish these trucks had a tach like the BMWs where the redline mark varies with the temp of the engine oil. Also nobody's mentioned the transmission, you cannot get balsy with your driving until the ATF is at least 120-degrees IMO, below that temp Dex-III does not shift correctly; Dex-VI is much improved in this regard.

 

I'll go so far as to say, if your engine needs more than 30-seconds fast idle to drive then something is in need of a tune-up.

 

Mr. P.

Edited September 17, 2008 by Mr. P. (see edit history)

[Hrtbeat1]

All my vehicles get warmed up before driving, even here in the south. I let the coolant get to 100 degrees and the oil temp guage just starts to move. Then I drive easy till I get to the highway, roughly 5 miles. Its all residential area with a 35 MPH limit till the highway anyway.

 

[KJT13]

once again I learned alittle more from Mr. P.

 

Seeing that I park under a bunch of bedrooms and leave here at 6:15am for work, I don't let mine sit for more than 30 seconds to a minute. Just usually till the pressure builds up and the idle comes down. I have a good 5 to 8 minute city drive before I hit the highway so my temps are usually pretty good by the time I'm at the bottom of the ramp.

[FireRescueSS]

When i'm responding to the FD during the night(time of year does not matter), the first thing I do is start the truck with the remote starter. By the time I get dressed and put my shoes on, 1-1/2 to 2 minutes goes by which gives the truck just enough warm up time to drive it.

 

 

You must be getting close to retirement... 45 seconds is all I need from a dead sleep, to my truck. Sometimes 60 if the porch is slick as hell, lol.

 

Anyway, I don't worry too much about my truck warming up in the summer time, never goes more then 15 hours, and that's mostly cause I work 12 hour shifts. When it cold, or somewhat cold, I let it sit and idle until the oil pressure as been built, the idle has came down and smoothed out (the computer is no longer avgressively warming) and the coolant temp is starting to be measured. Even then, I try my best not to romp on it until the exhaust has warmed up, and is barely noticible, and greatly reduced.

 

But, if it's an Fire/EMS run, she's ridden hard, and put away wet, or frozen. BUT, it's a chevy, she can take it. That is one reason why I can not use any forced induction.

[Fireman31]

You must be getting close to retirement... 45 seconds is all I need from a dead sleep, to my truck. Sometimes 60 if the porch is slick as hell, lol.

 

 

Time yourself next time speedy, I guarantee from the moment you wake up until you are pulling out of the driveway is over a minute........either that or you sleep on the couch in your clothes. I have timed myself, from the time I wake up until im pulling out of the driveway is about 1-1/2 minutes........2 minutes if there is frost on the window.......

[FireRescueSS]

either that or you sleep on the couch in your clothes.

 

 

Sometimes. Put I have everything in it's exact spot, and I 'drill' myself on my 'pattern' frequently. BUT, I also worked third shift for 3 years, I get up and at full alert in a flash, but I can't fall asleep.... But, we are only at 125 combined Fire/EMS runs for the year, your at what, 13,000? But I bet I'm gonna be slippin a bit soon, starting to age!

 

Anyway, get a remote starter on your truck. Mine is supposed to be a mile range, but it's a two-way remote... I start it when I leave my work station, and by the time I get on the other side of the plant, and clock out, and then get to my truck, it's been 4-6 mins.

[packjh]

Here in ga i usually give it about 30 seconds to warm up and i idle all the way down to my apt gate which takes about another 1.5 to 2 min.

 

In alaska in the winter i would let it warm up between 10-20 min depending on how cold it was outside or how quik i was in a hurry to get home. At -40 heated seats take a while to get warm.

[GetWithIt]

I just let mine warm up enough to lose the irritating "piston-slap" noise......usually around a minute or so...but, my truck is in the garage 99% of the time.

[F1SSS]

I always let my truck warm up until the rpms are at a certain point (its a hair over 500rpms). In the summer its always 1.5-2 minutes (garage keeps her cool) and during winter its at least 5 minutes....Last winter I was in the midst of being sick, nothing beat having that remote start coming out of the hospital when it was 10-30 outside.

 

Even after that I drive her real easy for the first 10 minutes and keep below 2000rpms.

Edited September 18, 2008 by 03maSSS (see edit history)

[Tzer]

I give her warm up time for about as long as it takes me to connect the iPod and put my seatbelt on. Roughly 30 Seconds or so.

 

If it's really cold or covered with ice or snow when I leave work I'll go out and start it before punching out, It may run 5 or 10 mins while I scrap the windows. OH GAWD! that time in nearing. Cr@p!!! I park in a garage so the moring start ups are usually as mentioned above regardless the weather.

 

I did the same routine with my 95 Z-71 for 12 years and never had a problem, But it may of been quicker because I didn't have an iPod to hook up. LOL