Duramax Dude (or lady) needed

[tdhanses]

https://www.dieselpowerproducts.com/blog/sema-2019-the-good-the-bad-and-the-questionable/

See Edge Pulsar about 2/3 way down in article. No idea on it, I just ran across that in looking at options.

Yeah but that’s not an emissions delete tune, it’s just modifying signals between the ECU and sensors.

 

[11boo]

I’m driving a 2003 duramax that I bought brand new. I haven’t done anything to it, mechanically speaking, but maintenance. Still runs and drives great.

Same experience with my 06. Just sold it with near 300k miles tho. Never modded, always reliable.

 

[WRM]

Yeah but that’s not an emissions delete tune, it’s just modifying signals between the ECU and sensors.

I didn't say it was. Between EPA and GM they are doing their best to lockout "emissions delete" tuning from new products. It's an option someone may want to consider for the newest engine. I don't have one and likely never will.

 

[KRATOCT]

LML does have a bad rap for injection pump issues. Yes the Bosch cp4 is a weak point but not as common as people make it out to be. I have a 16 and I haven’t done the cp3 conversion nor do I really plan on it at this time. I do strongly recommend a $250 part Exergy sells that everyone refers to as the Fuel System Saver. It’s an improved inlet metering valve that replaces the stock one. Stock valve has a single layer plastic screen to catch debris and if the pump does grenade, the shrapnel shreds this plastic screen and gets sent through the entire fuel system often taking out the piezo injectors, fuel rail, lines, tank etc should all be replaced, and of course the pump. A $10-12,000 repair. This fairly simple upgrade was the first thing I did on mine and I run Optilube XPD fuel additive. Probably the most highly rated from what I’ve read. There are no reported cp4 failures with this fuel system saver so it’s not proved that it does work but I don’t see why it wouldn’t. My thoughts are, the people willing to pay the small insurance policy to install it also take the proper measures of fuel additive, fueling up at well used gas stations and running a lift pump and that is all that is needed to keep the truck reliable, which is why I don’t see the need for a cp3 conversion. A lift pump is another very strong recommendation. I have the FASS titanium 100gph and I’m happy with the performance although the instructions can be a little confusing. I referenced YouTube for clarification.
With those upgrades and caution not to put bad fuel or gas into it, your LML should be a very reliable truck.
And if you don’t have emissions testing in your area just go for the delete. No DEF, no regens, more power, and Over 29 mpg if you’re not ripping on it all the time.

 

[JLane330]

I have an '06 LBZ, so not exactly the same as the LML's. Others have covered the CP4 issues already. I see someone mentioned head gaskets and studs. I did mine a few months ago. It's a very labor intensive job, and the parts aren't cheap. All told, I had about 56 hours doing mine in a van. The van makes it tougher in some regards, and easier in others (have full access to the back of the engine). It's not a job for the faint of heart, that's for sure. You might want to look into whether the LML's have head gasket issues. My personal opinion is that most engines with an iron block and aluminum heads will have HG issues at some point, especially in a diesel. The heads walk and the difference in materials means more expansion of the heads than the block. I like my Duramax, mostly, but have to admit, not sure I'd go with another one. I'd definitely not go with a newer one. Gas engines are less expensive to purchase, gasoline is less expensive per gallon, the maintenance and repairs are way less expensive, and with the crack downs on diesel deletes, gassers are less complicated given the modern diesel emissions systems. There are other advantages in the comparison as well. Of course gassers aren't perfect and have downsides too. Unless you absolutely need the diesel, you might want to strongly consider a gas truck. I'm real curious to see how the new 6.6 gasser works out for GM, and the 7.3 gasser for Ford.

 

[Fullfan]

Keep the fuel clean, Cat filters are a easy and inexpensive upgrade. Tuning is expensive but adds crazy power, also adds the chance to break something. Know several guys w 300-350k on stock Dmax’s, regular maintenance is the key.

 

[tdhanses]

I have an '06 LBZ, so not exactly the same as the LML's. Others have covered the CP4 issues already. I see someone mentioned head gaskets and studs. I did mine a few months ago. It's a very labor intensive job, and the parts aren't cheap. All told, I had about 56 hours doing mine in a van. The van makes it tougher in some regards, and easier in others (have full access to the back of the engine). It's not a job for the faint of heart, that's for sure. You might want to look into whether the LML's have head gasket issues. My personal opinion is that most engines with an iron block and aluminum heads will have HG issues at some point, especially in a diesel. The heads walk and the difference in materials means more expansion of the heads than the block. I like my Duramax, mostly, but have to admit, not sure I'd go with another one. I'd definitely not go with a newer one. Gas engines are less expensive to purchase, gasoline is less expensive per gallon, the maintenance and repairs are way less expensive, and with the crack downs on diesel deletes, gassers are less complicated given the modern diesel emissions systems. There are other advantages in the comparison as well. Of course gassers aren't perfect and have downsides too. Unless you absolutely need the diesel, you might want to strongly consider a gas truck. I'm real curious to see how the new 6.6 gasser works out for GM, and the 7.3 gasser for Ford.

Actually all the desirable gas engines recommend premium fuel to get their best efficency and diesel is cheaper then premium. Tons of issues with gas engines as well. My duramax 1/2ton engine only cost $950 more then the small 5.3 and was cheaper then the 6.2 gas option in the same truck.

I’ll take this avg mpg any day over a gas. This thing is cheap to drive compared to gas and the diesels come with a 100k warranty while the gassers only have a 60k warranty.

Also hand calculated mpg has been higher then the computer display every time and other owners have experienced the same results, so mpg was probably higher on the 400 mile avg below.

 

[awbowhunter]

To help with the CP4 pump, always run a factory filter, nothing aftermarket. Change it regular. Also keep fuel tank close to full. Within reason. Running regularly below a 1/4 tank and the recirculated fuel cannot cool off and your running hotter temp fuel through that CP4 which in turn results in more heat in the pump itself. A lift pump added is not a bad idea either.

 

[JLane330]

Actually all the desirable gas engines recommend premium fuel to get their best efficency and diesel is cheaper then premium. Tons of issues with gas engines as well. My duramax 1/2ton engine only cost $950 more then the small 5.3 and was cheaper then the 6.2 gas option in the same truck.

I’ll take this avg mpg any day over a gas. This thing is cheap to drive compared to gas and the diesels come with a 100k warranty while the gassers only have a 60k warranty.

Also hand calculated mpg has been higher then the computer display every time and other owners have experienced the same results, so mpg was probably higher on the 400 mile avg below.
View attachment 313522

Very true, diesel is less expensive than premium typically. I was under the impression that a lot of these HD gas engines would run fine on regular gas. Of course they all "recommend" premium these days it seems, but I'm not sure it's necessary.
As for tons of issues with gassers, some are better than others. Those GM 5.3's, at least of old, were pretty darn reliable. My personal experience with an old one (MY 2000) was that it'd get 20 on the freeway and mid to high teens in town. This was a 4wd version Sierra 1500. In the 200k+ miles, it's had very few repairs required.
That's VERY impressive mileage on your baby Duramax. Impressive! I might come to the same conclusion, especially if the price difference over the 5.3 was that little. Of course my hesitation has to do with injectors, pumps, and diesel emissions equipment. I keep my vehicles for a long time, so long term durability matters. I have read that the baby Dmax has some EGR and PCV oil issues. A catch can might solve the majority of issues, not really sure. Something to consider if you haven't looked into it yet.
Final thought, what is the cost of exhaust fluid + diesel vs gas? Just curious how much cost is added by the exhaust fluid. Maybe it's negligible compared to fuel?

 

[Ynothunt41]

I have a 06 LBZ and I put a air dog lift pump on it and it works great. I love my Duramax!!

 

[tdhanses]

Very true, diesel is less expensive than premium typically. I was under the impression that a lot of these HD gas engines would run fine on regular gas. Of course they all "recommend" premium these days it seems, but I'm not sure it's necessary.
As for tons of issues with gassers, some are better than others. Those GM 5.3's, at least of old, were pretty darn reliable. My personal experience with an old one (MY 2000) was that it'd get 20 on the freeway and mid to high teens in town. This was a 4wd version Sierra 1500. In the 200k+ miles, it's had very few repairs required.
That's VERY impressive mileage on your baby Duramax. Impressive! I might come to the same conclusion, especially if the price difference over the 5.3 was that little. Of course my hesitation has to do with injectors, pumps, and diesel emissions equipment. I keep my vehicles for a long time, so long term durability matters. I have read that the baby Dmax has some EGR and PCV oil issues. A catch can might solve the majority of issues, not really sure. Something to consider if you haven't looked into it yet.
Final thought, what is the cost of exhaust fluid + diesel vs gas? Just curious how much cost is added by the exhaust fluid. Maybe it's negligible compared to fuel?

I’m not touching a thing till warranty is up, messed with my last diesel and always worried about a warranty denial. I think issues have really been with a small set of people on Facebook that feel they are the majority, crap happens with all new vehicles. So far I’ve done nothing but drive and add fuel/def.

I would say in 10k miles and towing for more then half of that I’ve put in 12.5 gals of def maybe, if I wasn’t towing I’d probably drop 4 gals of def from that. I usually fill my def up at truck stops but I have bought 5 gals in jugs, I have spent maybe $53 in def, so at a cost of around $0.005 per mile in def or so.

Most expensive def I’ve used was $20 for 2.5gal from the dealer, bought a 2.5gal jug from Advanced auto for $11.99 and put 7.5ish in from the pump for under $3 a gal, didn’t keep track of the price but it was in the 2’s each time.

Overall I’d say at a cost of $53 in 10k miles the cost is immaterial.

Really I’m not as worried about emissions stuff anymore, if it needs fixed it’ll happen under warranty if I have it after it’ll just be a cost to keep it running.

I have an auxiliary fuel tank in the bed that holds 50gals, if I avg 27mpg that gives me a range of 1,998 miles on 74 gals, locally diesel at Sam’s is $2.88 a gal so almost 2k miles for $213.

My 2019 F250 got 11.9mpg always, so 167.9 gals with a reg price here of $2.89 and premium at $3.20, that’s a cost of $485 for regular or $537 for premium. Not sure what Sam’s price is but since you can’t use an aux tank with gas I’d say your avg price over 2k will be around $3 a gal for gas.

Now in 2000 miles I may use 2.5gals of def at a cost of around $10. So total cost of $223 to go 2000 miles vs $485 to $537.

Driving around town I avg 23mpg.

Towing my camper I get 15mpg into the wind where I got 8mpg with my F250, so a little closer in costs to tow and you do burn up more def when towing. The baby dmax pulls mountain grades much better then the 6.2 gas did, I do miss the weight of the 3/4 ton in the wind though.

I also bought my baby dmax for $12k below msrp in Feb due to rebates and sales and got what I paid for my 2019 F250 in trade, I hit that lucky transition period.

 

[NebraskaFlatLander]

I had my egr blocked off, dpf removed and a single eco/tow tune (efi live) on my 08 regular cab 2500 Dmax, went from 18mpg highway driving to 18mpg.... didn't change a thing and wasn't cheap.... my whole reason for deleting was economy and well that didnt workout but it woke it up a lot

 

[mxgsfmdpx]

Unless you’re deleting the DPF and EGR there’s no way this is going to be a “rest of my life truck” unless you only plan on living another 7 years.