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ChopperBill
09-19-2002, 07:36
How long do you guys and gals warm up your D-Max before taking off. I usually never warm up an engine but take it pretty easy until it reaches operating temp. Heard this was ok to do. With winter around the corner I am sure that will change as the D-Max has 15-40 oil installed.

Kennedy
09-19-2002, 09:00
Opinions will vary, but I seldom even move my truck with less than 5 minutes of idle time in summer, and more in winter.

My next project will be a BD exhaust brake primarily used as a heat riser to hold in some EGT for faster warmup.

My remote start timer is set at 24 minutes run time, and I often don't get out to the truck before it "times out"

Colorado Kid
09-19-2002, 09:49
Like John said, opinions are all over the map.

I generally follow the routine you stated...a mile or so of very slow and easy (less than 1500 RPM), then stay gentle with it until normal operating temp...but I do park in an attached, but not heated, garage.

When I drove school busses we had mandatory 15 minute warm up before moving at all, even in warm weather. The drill was slow idle for 1 minute and then 1,000 RPM for at least 14 minutes. They all had block heaters and were plugged in if below 40* was expected. If below 10* the mechanics reported to work 2 hours early and started them all, so they warmed up 2-2.5 hours while still plugged in! The mechanics swore that the engines would be gravely damaged if any load was put on them with less than 15 minutes of warm up.

Meanwhile down the street at the firehouse the drill was crank and go hard. The Allisons don't like that service, but the engines really don't seem to give the firefighters any more trouble than the bus drivers.

I can't bring myself to hammer it while it's still stuttering, but I'm pretty sure the long idle time is not really helpful. Allisons book on the 1000 says it needs a minute of idling before engaging a drive range, and I think that is about how long I'd wait.

If the thick oil worrys you there's 5W-40 synthetic that meets all the appropriate specs in Mobile Delvac 1 and Shell Rotella T brands.

Burner
09-19-2002, 10:48
Just hang out with your ride. Listen to the engine when it's warm. When you start it up in the morning, listen for that same sound. After a while you will be able to hear the temp....sort of. Just remember that a little more warm up time won't hurt it but, too little may be destructive. I have used this method for years on all my Diesel equipment. ---- (3) 300 PC's, (3) TD-15's, (3) Backhoes, (3) dumptrucks, (2) track loaders, (2) rubber tire loaders (1) 570-A motor grader, (1) read 90 screen all, (2) Dynapac 251's, (1) lowboy tractor [ Cummins 400 POS!], (1) 743 bobcat and (1) 2002 GMC Duramax. I think that warm up is 20% of the life, cool down is 30% of the life and maintenance is the other 50%. That's just my .02 worth .... or 3 million dollars worth of equipment observation. Think about it this way...... I could buy a top dollar D-Max for the same price as two new big engines. :eek:

Burner

jqqd
09-19-2002, 11:35
I wonder if it really makes much difference warm or cold. My company sold big V8 Cat generator sets that crank and go to full power online in less than 15 seconds with no problems.

MadDuraMax
09-19-2002, 15:11
I live in town, so I have 3 to 4 miles at 25 to 35 MPH before I hit the back roads to work. By then the engine temp (so far this year) is 140 to 150f. This "slow drive" has been recommended by the OEM's for awhile now on both gassers and diesels to my knowledge.

I park outside, so in the winter it will get the "warm up until the windows defrost". Sounds simple, but it's worked for 25 years or so.

Mark

Diverguy
09-19-2002, 15:24
I can not tell you what a Duramax will do in temperatures below zero Celsius but my 6.5 just doesn't want to shift easily into 2nd gear if I operate without a short warm up period. It feels like I'm forcing the engine. Five minutes usually works and 8 minutes maximum. Then again it depends on the oil viscosity you are using. Depending on how cold it gets I use 10W-30 or 5W-30 which really helps for start ups. smile.gif

GMC-2002-Dmax
09-19-2002, 19:06
I guess I was always taught that an engine will warm up faster when you are driving it that when you are idling it.

In the morning I give my truck about 30 seconds to a minute of idle in warm weather and then I back her out of the driveway. It takes me about a minute or two more to get to the main road and then I drive her easy. When I see the temps coming up to around 160 or so I drive normal.

If I stop somewhere and then start her up and she's close to operating temp I don't bother to sit and idle I just drive her.

I may be missing something but I could never get a truck to warm up in the winter by idling it for 10-15 minutes, but when I took it down the road I got it up to temp a lot faster.

Am I missing something here???

GMC :confused:

TBC
09-19-2002, 19:37
I follow about the same procedure as the post above. I use the volt meter as my warm up gage when cold. When I start the battery volts are about 9 volts. I wait until it comes up to about 14 volts which is normal voltage and then put it gear and drive out of the neighborhood slowly. This warmup takes about a minute at most. By then the temp is coming off the gage bottom. From there I drive normally. The eng does mind and the trans shifts normally. I am an aircraft mech so it will get some warmup as I have been doing for years. I cringe everytime I hear someone start and engine and then rev the engine up to high RPM.

[ 09-19-2002: Message edited by: TBC ]</p>

torque
09-19-2002, 22:04
A few years back GM or Ford (I forgot which) did some testing and said that 20 seconds was optimum for gassers. Less didn't get the oil far enough and more pushed too much raw gas by the pistons. I haven't heard about diesels.

tpitt
09-19-2002, 22:52
J.K.,
Just installed my BD brake today. Sell you one cheap. :D :D :D Terry

deerhunter7
09-21-2002, 17:30
ChopperBill , The best way I found not to worry about warm -up is to have the engine warm before you start it . Between the block hearter and the Espar Engine Preheater mine never sees cold start at anything below 40 degrees . Some of the most engine wear is at cold start . The colder it is the more the metals contract leaving more clearance. Plus you do'nt have instant oil pressure so a little metal to metal every cold start means faster wear . I had a guy at a campground bragging to me how his Ford Diesel started in sub-zero weather. Said it smoked rattled and knocked for a couple minutes. I just asked him how many times he thinks he can do that and have a healthy engine. Wasn't so proud then. Showed him my Espar and he decided to get one.. tongue.gif