Turning the Duramax on and off frequently. Help.

QUIKAG · March 21, 2003

Okay, my brother is going to be the proud owner of an '03 2500HD D/A truck tomorrow. He mows lawns for a living right now (though he has a master's degree in accounting ) and I want to give him good advice.

Let's say he mows 30 lawns in a day which he will be doing frequently in the heat of the summer, should he leave the truck running while he mows a yard. Let's say the yard takes 15 minutes to mow, should he leave the truck on? What if it's a 45 minute yard? At what point should he leave the truck on versus turning it off?

Also, why is it bad to start and stop a diesel frequently? This will be my 'families' first diesel and we want the truck to last. Thanks!!

Shaners · March 21, 2003

I'm not a diesel pro, but I would think that as long as the motor is up to temp then shut it off.

The new diesels are much better as far as starting and shutting off than the old ones, so I think as long as the motor is warm, and the outside temps are decent, then shut it down...

The biggest concern I would have is the billion quarts of oil in the oil pan... If they aren't warm then condensation in the oil would be a concern. If your Bro mows a few small lawns in the AM, then let the thing run. Otherwise I'd shut it off...

But I've never owned a diesel before... so what do I know!!!

BDBWTE · March 21, 2003

Tell him to get a high idle or idle lock and let the truck idle.. It's a diesel it won't hurt it... In the summer sometime our diesels idle all day on a jobsite...

clk7711 · March 21, 2003

I really don't think its gonna hurt anything turning it on and off. If he's gonna let it idle then do what BDBWTE suggesest and get the idle controller.

t-76y2kss · March 21, 2003

I stop and start all day on job sites in my 03 Dmax with 0 problems.Like Shaner said in the morning less than 50 deg let it get to operating temp dont want those 10 qts of oil to let moisture buildup.Repeated starting of modern diesel is not a problem,with old if you shut it down it might not start again.Excellent choice.

Roofer · March 21, 2003

I wouldn't worry one bit about starting and shutting it down often in warm weather. I personally don't like leaving it run long with low oil pressure that these seem to idle at when warmed up.

Sure it might not last 500,000 miles like a truck that is driven constantly, but I would be surprised if it doesn't hit at least 300K with very minor problems.

Wormburner · March 21, 2003

Where do you buy an idle controller or the high idle kit?

I have a 2003 D/A, but can only find info. on 2002 and older.

Thanks.

Polaris Man · March 21, 2003

Go to thedieselpage.com , read the forums there, do a search for high idle, you will find the info you need, I think from what I read there that the 03 and 02 are the same for the high idle procedure.

QUIKAG · March 21, 2003

Thanks for the info guys. So, I'll tell him to let it run in the morning for the first few yards and then just start shutting her down as normal from then on out. Here in Dallas, Texas it'll be nice and warm so there should be no condensation buildup in the oil.

He should be picking the black beast up today. It's an extended cab, 4x4, LT trim, duramax allison with practically every option known to man including XM radio and all the other goodies.

It's a demo with 4,000 miles. The owner of one of the larger Chevrolet dealerships in the country, Tom Durant of Classic Chevrolet in Grapevine (he owns numerous other dealerships too) drove the car as his personal ride for those miles. It has a spray in bedliner and it doesn't look like the receiver hitch was ever used. He also had his 'personal Mexican' (as he put it) hand wash his truck every other day or so. The paint finish is very smooth and deep. :thumb:

silverado3500 · March 22, 2003

Tell him to get a high idle or idle lock and let the truck idle.. It's a diesel it won't hurt it... In the summer sometime our diesels idle all day on a jobsite...

I'm with BDBWTE, get the high idle controller and let it idle in the mornings, then possibly in the later afternoon you might shut it down for the longer yards only. I'd let it run on anything short of 30-40 minutes.

QUIKAG · March 22, 2003

Could you elaborate on what exactly a high idle controller is? I have not registered on the diesel page. I guess it bumps the idle up a bit to keep oil pressure a bit higher when stopped for extended periods? Is that correct?

BDBWTE · March 24, 2003

Idle lock, controllers, high idle switch...all idle the motor up and keep maintain a high rpm instead of the normal 500r's that it would have at idle.. This help to burn the fuel more efficently so as not to wash your pistons out. As well as keep oil pressure up and the fan turning faster.... There are more reasons but they are pretty much self explanatory.. Big trucks have idle locks on them.. We do it just because we are in and out of these trucks all day and turning them off for 15 min then running down the road 20 miles offers problems.. Even the DA's don't like it.. When you turn them off and on literally dozens of times in a day it's just harder on the motor, starter, etc.... We just let them idle...I have absolutely no issues with letting them idle we have a 6.9 Ford that has 468,000 miles on it and it still runs and runs sometimes all day...but she's a tired truck...Won't pull an air coompressor....I'm being serious...

QUIKAG · March 24, 2003

Thanks for the explanation, BDBWTE! One thing that has surprised me about my brother's now old '99 Z71 extended cab is that he has never had problems with the starter, alternator, or battery. Very surprising on a GM product that sometimes is started and stopped over 40 times in ONE day. The truck when traded in will have right at 100,000 miles and around 3450 hours on the motor. Still running great.