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I have often wondered if the refineries really blend fuel for the north and south or just give us all winter or summer blend. Seems like they would just ship the same product to both places depending on time of year.
As for last winter in Texas- never plugged mine in but I always use Power Service in all my diesels as its made down the road here. The Kubotas weren't happy starting in the cold and rattled for a bit but all ran good.
 

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Just go under the settings on your touch screen. I believe it's "comfort and convenience" and turn on elevated idle, which will kick up on cold starts to get things moving quicker.

I too run Optilube as Viper suggested (Because he makes me spend all my money) I'm on my second winter in North Jersey, zero special treatment and zero issues to date. Not as cold here as some of these guys see but its not uncommon to go single digits for a week or two in Jan plus the snow. I appreciate seeing a new guy try to stay ahead of things!
There is no elevated idle on the LM2. That option in the settings doesn't do anything. There is a bulletin for it that removes the option since it is misleading.
 

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There is no elevated idle on the LM2. That option in the settings doesn't do anything. There is a bulletin for it that removes the option since it is misleading.
Copy of bulletin?
Link?

Maybe it will say why mine idles up on cold start-up.
 

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2006 LBZ, 2009 LML, 2022 L5P (on order). 1993 6.5 parked in the shed.
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I have often wondered if the refineries really blend fuel for the north and south or just give us all winter or summer blend. Seems like they would just ship the same product to both places depending on time of year.
As for last winter in Texas- never plugged mine in but I always use Power Service in all my diesels as its made down the road here. The Kubotas weren't happy starting in the cold and rattled for a bit but all ran good.
Winter fuel (or #1) is more expensive to make. It also returns lower fuel mileage so big fuel users hate it. It is rare in the US to get straight number 1 that isn't labeled as such (some upper midwest, northern plains and upper New England places will sell it as pure #1). Canada, #1 in 90%of the country by about Dec 15th...crap mileage and the price goes up.

Case in point. Flying J, Sioux Falls SD, February......it's straight number 2 with a 2.5 gallon jug of additive (Tellico) dumped in per 8000 gal tanker load. Funny side note, it also turns to goo before you get to Minneapolis....ask me how I know.
 

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Copy of bulletin?
Link?

Maybe it will say why mine idles up on cold start-up.
Here you go. It doesn't have any sort of bulletin number/ID but this is what I was given, and explains why mine doesn't go over 900-1000 RPM on a cold start. Disappointing but oh well.

Computer Font Screenshot Rectangle Technology
 

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I use Hot Shots EDT in mine every fill up and Hot Shots diesel extreme right around every oil change. In the winter I drop the amount of EDT and supplement with the white bottle Power Service. I've never had any issues down into the single digits, however, unlike most of the guys commenting my truck seems like it takes a long time for the glow plugs to heat up even at temps as high as the 40's. It can sometimes take up to 5 seconds for it to warm the plugs before it will crank.
 

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I believe here in my zip code in NJ the fuel is blended winter fuel, not straight #1, But I have already noticed a lower fuel mileage, combination of things, longer warm-up time, and winterized fuel. have seen 7 mpg less.
 

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Sorry about the delay getting back.
Thanks for the pic.


On cold weather cold starts, mine i also idles about 900.

Regen idle is a little less than that 800 - 850?

In warmer weather it also does some of the slightly higher than 'normal' idles that can be commanded by BCM/ECM for electrical system purposes.

I've run LLY, LMM, LML and L5P 6.6's.
This little LM2 seems to warm just as fast, and perhaps faster than any of them did.

I've had always assumed that for this engine the 'elevated idle' (if it existed) had been set to a different rpm than the 6.6L

Mine always live outside.


I should check the trans temp after letting cold start idle for awhile on of these below freezing mornings.

With the 6.6's, I always thought the the transmission warmup was one of the elevated idle benefits. (as opposed to using a block heater to warm coolant)
 

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I believe here in my zip code in NJ the fuel is blended winter fuel, not straight #1, But I have already noticed a lower fuel mileage, combination of things, longer warm-up time, and winterized fuel. have seen 7 mpg less.
Where in NJ are you at? Most the diesel pumps in North Jersey say "winterized diesel" right on them around early Nov. I havent seen much reduction in MPG though, but i also throw XPD in every tank and have the Derringer (and I'm an L5P)
 

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My neighbor has 3.0L diesel and he also said he noticed the reduction in MPG the last 2 tank fulls, we live in Warren County. to be honest I even noticed MPG drop this time of year with my gas truck as they boost the alcohol content, I have found up to 35% alcohol in the past, and I never ever used E85 or any other alcohol mixtures, first 9.9% was legal and I believe now its 14.99% and they do not need to post gasohol as long as percentages stay below the 9.9/14.99, but wonder how I ever measured 35% bothers me for sure.
 

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I just got my '22 Silverado 3.0 this weekend. I am in Atlanta so we don't have too much cold weather - but there are a few days per year. I have had a diesel the last few years but it was smaller and fit in my garage. This truck doesn't quite fit and will have to stay outside so I have a couple of new questions. At what temperature should I use a diesel fuel additive? At what temperature and duration might I need to use the block heater? Is there a thermostatic switch available that can be attached to the block heater or extension cord to only turn it on below the specific temperature so it doesn't have to run excessively or all night?

Thanks in advance.
Diesel fuel additives are snake oil and will do nothing for your engine, other than drain your wallet. Buy good quality diesel, normally from a commercial truck stop is the best bet. Modern diesels will start unaided down to a very low temp, probably 0f, in Atlanta I doubt you will ever need to plug your truck in.
 

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2019 GMC Sierra 2500HD AT4 Crew Cab L5P Duramax
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Last year i never plugged mine in even when down to -13*, started up just fine.
One night last year when the overnight temps were -10 or lower, I purposely did not plug in the truck to witness a cold start the next day. At around 11a, the temp was in the single digits, I fired her up. She started but it sounded like a couple of angry bears.
 

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2021 Silverado RST 4x4 3.0L crew
Live in North West side of NJ. Warren County seldom goes below 10Deg. But not a big deal for me to plug it in, would you say beneficial to longevity to plug it in, and will it stress the heating unit if I plugged it in for 2/3 days straight and left it while not home?
Is it thermostatically controlled so it only lets the heating element work below a certain temp?
 

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2021 Silverado RST 4x4 3.0L crew
Live in North West side of NJ. Warren County seldom goes below 10Deg. But not a big deal for me to plug it in, would you say beneficial to longevity to plug it in, and will it stress the heating unit if I plugged it in for 2/3 days straight and left it while not home?
Is it thermostatically controlled so it only lets the heating element work below a certain temp?
I don't think it is necessary to do anything special. These aren't our grandpa's diesels. I can't provide details on the block heater but I know it isn't needed in your location. Guys in Canada don't use them.

I see those temps in NY and have never used the block heater.
 

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I don't think it is necessary to do anything special. These aren't our grandpa's diesels. I can't provide details on the block heater but I know it isn't needed in your location. Guys in Canada don't use them.

I see those temps in NY and have never used the block heater.

Yes, I believe it's not necessary, but it would be a benefit to the driver if it heats up faster? Other than that benefit any negatives? Leaving it plugged in for 2/3 days in a row when not driving it?
 

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As I understand it, the new 3.0s cam be plugged in for 3 years straight. There is a built in algorithm that will only turn on the heater if/when its needed.

Our L5Ps don't even have black heaters fixed at this point. Twice the size motor, significantly larger area to warm up plus fluids etc and they don't slip a beat. You'll be ok, she may just get a little cranky here or there.

I hit my autostart this am after sitting all day yesterday. Truck was covered in the snow. She turned over in about half the first crank. Sure she was a but grumpy at first but all good
 

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Yes, I believe it's not necessary, but it would be a benefit to the driver if it heats up faster? Other than that benefit any negatives? Leaving it plugged in for 2/3 days in a row when not driving it?
Well, there is always some benefit, but it does chew up some electric. It's like heating your swimming pool but you're not swimming in it....
I only plug any of my diesels in when they are subjected to the seasons coldest temps and I KNOW I'll be driving them the next day,etc. Other wise to plug them in for days just wastes electricity...
 
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