Chevy and GMC Duramax Diesel Forum banner

1 - 20 of 30 Posts

·
Registered
Joined
·
30 Posts
Discussion Starter #1
Well, I might be buying my first diesel....well 2nd if you count a Jetta TDI.

Thinking about upgrading my 1/2 ton 5.3 and I'm a little spoiled with fuel economy (somewhat). So I've done quite a bit or reading and have a good idea of issues and fixes that I can expect at some time (possibly). The LB7 - injectors, maybe head gasket. The LLY - injector harness/ice pick mod, maybe head gasket. Those seem to be the main things that I have noticed.

LB7
One thing I really like about the LB7 is the fuel economy which seems to be pretty awesome. I understand the power is lower, but with tuners and everything else, it'll have plenty more power than what I will ever need. I'm also starting to see these become pretty cheap.

In terms of the injectors. I've tried searching and it seems mixed, but how are the newest bosch injectors holding up? I understand that many people put different filtration on them and I don't recall seeing everyone agree that filtration fixes it.

LLY
Obviously more power, but nowhere near as much mpg. Seems like these don't have the injector issue which is great. Also, the location of the injectors is a benefit.

I've read where some people have removed some emissions stuff and after a tune, they have gotten near LB7 mpgs. Is that actually common, or is that just like any forum where some people exaggerate numbers?

I was just debating on going with a 2001 2500 6.0, but I just drove one recently and it really didn't seem like it had much more power than my 5.3. I figured that I could get a cam and tune and be close to the same power as that 6.0.

What do you guys think the LLY fuel economy and LB7 new injector issue (yes, yes, I know, it's a truck, not a fuel mileage vehicle, but a 30% difference in fuel economy can add up)
 

·
Registered
Joined
·
30 Posts
Discussion Starter #4
Skip ahead and get a 6 speed Allision.
Hell, might as well skip ahead and just buy a brand new truck with a warranty. lol

But seriously, I have a very low budget and it seems that only LB7 and LLY's are in that range.

I've actually started looking at the older cummins engines. I like how simple they are. Really don't like dodges though, but this is just going to be a vehicle that tows around 10-12k lbs here and there.
 

·
Registered
Joined
·
626 Posts
Hell, might as well skip ahead and just buy a brand new truck with a warranty. lol

But seriously, I have a very low budget and it seems that only LB7 and LLY's are in that range.

I've actually started looking at the older cummins engines. I like how simple they are. Really don't like dodges though, but this is just going to be a vehicle that tows around 10-12k lbs here and there.
The 2006 LLYs had the 6spd...
 

·
Registered
Joined
·
30 Posts
Discussion Starter #6
The 2006 LLYs had the 6spd...
Good to know. I'll keep a look out. Still leaning towards the cummins engine. In the perfect world Chevy would have a cummins in it. I love the look and body style of the early 2000s silverados. It's hard for me to get rid of my 2001 gasser.
 

·
Registered
Joined
·
1,084 Posts
The problem with the older Cummins motors is that they are hooked to a Dodge. That and they are obnoxiously LOUD. I've owned my LB7 since new. There used to be millions of those old POS Dodge / Cummins trucks around here. They must have sold a bazillion of those things. Used to absolutely HATE it when some moron would pull up to the diesel pump and leave one of those POS idling. Now I don't have to worry about that anymore. I rarely ever see those old Dodge trucks on the road. The motors are probably still running, it's just that the rest of the truck has completely fallen apart. I see one maybe every 6 months on average.

OTOH, there are still MANY LB7 trucks on the road. Heck, out of ~18 houses on my street, 4 guys are still driving LB7 trucks. They seem to hold up much better than the Dodges around here. I still see them everywhere.

What kind of mpg are you expecting from a LB7? Mine has got roughly the same mpg for the past 411,000 miles.
On the highway with cruise on 75 mph it get 19.6666666666666.
In town depending on traffic and how big a hurry I'm in, I get anywhere from 15.5 to 18.6. Usually it's in the range of 16-17.
Towing 10,000 lbs with cruise on 72 - 10 mpg.
Towing ~5,000 lbs with cruise set 72-77 mph 13ish mpg.
I've seen others claim better mpg but not sure how much of all that I believe. Maybe with a tuner? Mine is bone stock.

If you go with an LB7, it's a pretty simple motor. If it's not California it has no PCV, no EGR - basically no pollution crap at all. It's just the injectors that are the problem. Maybe / hopefully that problem is now a thing of the past with the newly available SAC type injectors. The stock size of these have only been out a year or 3 now and that's just not enough time to conclude that they are the answer. In my experience, fuel filters, lift pumps and fuel additives don't do crap to solve the problem. I've tried all of them and have got 80k miles out of every set of injectors. EVERY set- no matter what filter, with / without lift pump and with / without fuel additives. 5 sets so far.

Good luck whichever way you end up going.
 

·
Registered
Joined
·
117 Posts
Buy the truck that you get the best deal on, LB7s are great if your aware of the injector issues. As far as MPGs go, every individual truck is so different you never know what your going to get. There are LMLs and LBZs out there that get better mileage than some LB7s, in my experience every truck of the same series is not created equal. But yes in general LB7s are decent mileage getters.

The old 5.9 Cummings is a great motor because of its simplicity but as longtimedmax said the problem the motor is stuck in a Dodge truck. Your probably going to hate one of those coming from your 1500 Chevy. The computers in the Dodge that check the MPGs are generally way off. I work with a guy (full of shit) that tells everyone he a gets 25 mpg in his 2006 Mega turd. We went on a road trip, I brought my gps and checked the miles divided by the gallons. We got around 16mpg, we were hauling ass and my LB7 would have got around the same at those speeds. A good friend of mine who is anal about MPGs and not full of shit has a 2005 5.9, our trucks get about the same.

See my sig for my LB7s mods, most important a heavy wheel and tire combo H2s and 35" Toyo MTs. If I drive like my 75 year old Mom and I am very carful sure I can squeeze out 20MPGs. That's not realistic though, on a road trip best case scenario going 75mph probably going to barely break 17mpgs. 8000# toy hauler gets 10-12mpgs depending on elevation change.

If I was looking to buy a 10, 15 or 20 year old vehicle the most important thing to me would be the vehicle condition and maintenance records. I would only buy from a long term owner with perfect maintenance records that didn't beat on their truck. I would stay away from car lots with an unknown history unless it was one hell of a deal. Sometimes deals get expensive real quick, especially in the diesel world. A head gasket and set of injectors in a Duramax could put a lot of gas in a 6.0 gas 2500. Good luck, post up your new truck when you get it!
 

·
Registered
Joined
·
30 Posts
Discussion Starter #9
The problem with the older Cummins motors is that they are hooked to a Dodge. That and they are obnoxiously LOUD. I've owned my LB7 since new. There used to be millions of those old POS Dodge / Cummins trucks around here. They must have sold a bazillion of those things. Used to absolutely HATE it when some moron would pull up to the diesel pump and leave one of those POS idling. Now I don't have to worry about that anymore. I rarely ever see those old Dodge trucks on the road. The motors are probably still running, it's just that the rest of the truck has completely fallen apart. I see one maybe every 6 months on average.

OTOH, there are still MANY LB7 trucks on the road. Heck, out of ~18 houses on my street, 4 guys are still driving LB7 trucks. They seem to hold up much better than the Dodges around here. I still see them everywhere.

What kind of mpg are you expecting from a LB7? Mine has got roughly the same mpg for the past 411,000 miles.
On the highway with cruise on 75 mph it get 19.6666666666666.
In town depending on traffic and how big a hurry I'm in, I get anywhere from 15.5 to 18.6. Usually it's in the range of 16-17.
Towing 10,000 lbs with cruise on 72 - 10 mpg.
Towing ~5,000 lbs with cruise set 72-77 mph 13ish mpg.
I've seen others claim better mpg but not sure how much of all that I believe. Maybe with a tuner? Mine is bone stock.

If you go with an LB7, it's a pretty simple motor. If it's not California it has no PCV, no EGR - basically no pollution crap at all. It's just the injectors that are the problem. Maybe / hopefully that problem is now a thing of the past with the newly available SAC type injectors. The stock size of these have only been out a year or 3 now and that's just not enough time to conclude that they are the answer. In my experience, fuel filters, lift pumps and fuel additives don't do crap to solve the problem. I've tried all of them and have got 80k miles out of every set of injectors. EVERY set- no matter what filter, with / without lift pump and with / without fuel additives. 5 sets so far.

Good luck whichever way you end up going.
Honestly, all I need in a truck is something with more power than my 1/2 ton 5.3. Love the truck, just need more power. The 6.0 in my 3/4 ton just doesn't seem to impress me either. Plus the mpg isn't great.

I agree about the dodge truck. I'm not a dodge guy at all. Shitty interior, don't like the look, of course the stupid front suspension, but like the simplicity of the cummins. I don't mind that they are loud. One thing I like is the manual trans. It seems that I can find them in the dodge more. Also, it just seems that if there is an issue, it is far easier and cheaper to fix.

In terms of the LB7, the injector thing is what worries me. Spending $2500 on injectors every 80k is a little ridiculous IMO. Heck, the diesel trucks im looking at are in the $3500 to $4k range. I am a chevy guy, so I might bite the bullet and get one. Gosh damn it why can't there just be a cummins in a chevy (yes, i know, ppl swap them).

Now, there is another option. The powerstroke. Not a fan of ford at all, but I might.....might consider a 7.3 with a manual. I prefer the body style and interior on the fords compared to the dodges. I think those engines are pretty stout too, but I'd have to do more research. Seems like they have smaller petty things. I have noticed though that quite a few I see actually have problems with the manual trans. That seems odd and it could just be a bad clutch that ppl confuse for trans or people that try to drive them like stock cars and jam them in gears. not sure. I think the powerstrokes get a good bit worse MPGs than a cummins or duramax. Not sure though. Just started looking them up.
 

·
Registered
Joined
·
130 Posts
If your after power dont get a 7.3. They are dogs.

The 6.0s can be nasty if built right.

If power is all your after, have you considered a 1500 with the 6.2? They have some get up and go power to them. It's a different kind of power though. Still a really fun truck to drive, and get decent fuel milage.
 

·
Registered
Joined
·
30 Posts
Discussion Starter #11
Buy the truck that you get the best deal on, LB7s are great if your aware of the injector issues. As far as MPGs go, every individual truck is so different you never know what your going to get. There are LMLs and LBZs out there that get better mileage than some LB7s, in my experience every truck of the same series is not created equal. But yes in general LB7s are decent mileage getters.

The old 5.9 Cummings is a great motor because of its simplicity but as longtimedmax said the problem the motor is stuck in a Dodge truck. Your probably going to hate one of those coming from your 1500 Chevy. The computers in the Dodge that check the MPGs are generally way off. I work with a guy (full of shit) that tells everyone he a gets 25 mpg in his 2006 Mega turd. We went on a road trip, I brought my gps and checked the miles divided by the gallons. We got around 16mpg, we were hauling ass and my LB7 would have got around the same at those speeds. A good friend of mine who is anal about MPGs and not full of shit has a 2005 5.9, our trucks get about the same.

See my sig for my LB7s mods, most important a heavy wheel and tire combo H2s and 35" Toyo MTs. If I drive like my 75 year old Mom and I am very carful sure I can squeeze out 20MPGs. That's not realistic though, on a road trip best case scenario going 75mph probably going to barely break 17mpgs. 8000# toy hauler gets 10-12mpgs depending on elevation change.

If I was looking to buy a 10, 15 or 20 year old vehicle the most important thing to me would be the vehicle condition and maintenance records. I would only buy from a long term owner with perfect maintenance records that didn't beat on their truck. I would stay away from car lots with an unknown history unless it was one hell of a deal. Sometimes deals get expensive real quick, especially in the diesel world. A head gasket and set of injectors in a Duramax could put a lot of gas in a 6.0 gas 2500. Good luck, post up your new truck when you get it!
I do agree that the cost could put a lot of fuel in the 6.0, but honestly my 6.0 is a 4x4. I really don't want an older 4x4. I don't offroad or anything and they never seem to be as comfortable to me. I've only needed 4wd twice in the last 5 years and I'm probably going to throw my old HF winch on the front of my truck for a just in case situation.

The problem with the 6.0 in my truck is that it's only rated at 10k lb towing capacity. If I throw a 3.73 in my current half ton, the towing capacity is 8300lbs. not much of a difference.

Realistically the biggest load I haul will be around 12k and it won't be that often. I flip cars and looking to get into bigger trucks.

I'd really just like to update my 1/2 ton since I'm attached to it, but it's going to be pushing it. Realistically a diesel is over kill, but the gassers are under kill.

Again, my budget is low. With my 6.0 crew cab 4x4, I can sell it for about the same price as I can find an older 2wd diesel. I'm not 100% against the 3/4 ton gasser, I just got it on trade and idk, just doesn't wow me. I mean, will it really do that well climbing up a hill with a 10k load?
 

·
Registered
Joined
·
130 Posts
The 6.0 gas motors arent the most powerful things out there, but they will work hard and be reliable for cheap.

They wont be the fastest up the hill but they will do it. Also I've found the stock tuning to be pretty poor on them. A good tune wakes them up nicely. Not insanely different, but a noticeable change for sure.
 

·
Registered
Joined
·
30 Posts
Discussion Starter #13
If your after power dont get a 7.3. They are dogs.

The 6.0s can be nasty if built right.

If power is all your after, have you considered a 1500 with the 6.2? They have some get up and go power to them. It's a different kind of power though. Still a really fun truck to drive, and get decent fuel milage.
The 7.3 has plenty of torque for what I need. I'm not pulling 25k loads. Any diesel (especially with a small tuner) will be plenty of power for me. Don't get me wrong, I'm sure I'll get the power bug if/when I get a diesel.

IN terms of the 6.0, yes, I've looked up all kinds of things but the main thing is low end power on the LS engines. They are a little lacking. I could sell my 6.0 truck for about the same price as an older diesel. So, does it make sense to make a gasser have close to the same torque as a stock diesel? or just get the diesel and never need more power. I am itching to build something, but let's say you get a towing cam (which doesn't add a ton of low end power, but does help), springs and a tune, you are look at around $1000 or so.

In terms of a 6.2, that'd be awesome, but way out of my price range. I'm dealing with early 2000s trucks. I guess I could look up a 6.2 swap. And sell the 6.0. I haven't really looked into everything that is involved in that swap, but it probably woudn't be too bad. That might do everything I need. I think what helps the 6.2 is the transmission. I think they have 6 or 8 speeds. I'm not 100% sure on that. Would have to do more research. Would be cool though.
 

·
Registered
Joined
·
30 Posts
Discussion Starter #14
The 6.0 gas motors arent the most powerful things out there, but they will work hard and be reliable for cheap.

They wont be the fastest up the hill but they will do it. Also I've found the stock tuning to be pretty poor on them. A good tune wakes them up nicely. Not insanely different, but a noticeable change for sure.
Yeah, I really like the LS lineup. I mean I can swap head gaskets and bolts for like $100 plus labor. Just had to do with my 5.3.

I do tend to go overkill sometimes with vehicles.

The most I would tow is a 20 foot trailer and maybe a dually on it (would be the biggest thing). Usually it's just average vehicles.
 

·
Registered
Joined
·
130 Posts
I meant 6.0 as in the power strokes.

They have their issues, but they are can be good motors if you take care of their downfalls. Available with a manual trans if that's what you prefer as well.

But they are a pain to work on and it's in a Ford, which are equally bad to work on. I work for international, so we still get in quite a few vt365s(6.0) and some 444e(7.3). They can last for sure.
 

·
Registered
Joined
·
30 Posts
Discussion Starter #16
I just know where I can get a 2wd lb7 with the fass fuel system and supposedly newer injectors for around $3500. It has over 400k miles, but supposedly runs great. Who knows if it really has newer injectors though. Ppl will say whatever to make you happy.
 

·
Registered
Joined
·
30 Posts
Discussion Starter #17
I meant 6.0 as in the power strokes.

They have their issues, but they are can be good motors if you take care of their downfalls. Available with a manual trans if that's what you prefer as well.

But they are a pain to work on and it's in a Ford, which are equally bad to work on. I work for international, so we still get in quite a few vt365s(6.0) and some 444e(7.3). They can last for sure.
nope nope nope. Not getting a 6.0 powerstroke. Nope. Only ford I'll get is the 7.3. Im already not a ford guy, so I have a very fine line if I were to get one.
 

·
Registered
Joined
·
1,084 Posts
The reason you find a lot of Dodge / Cummins trucks with manual transmissions is because everyone knew the automatic trans was good for 100k miles or lees - so they ordered / sold tons of them with manuals.

Injectors don't cost $2500 per set. Most I ever paid was about $1900. But yes, still ridiculous. 80k miles/set is my numbers but that can vary drastically from truck to truck. The average seems to be around 120k-130k per set but I've seen guys say as low as 40k miles and others who are still on their factory set at 200k+ miles in. As I mentioned, the new SAC00 should be THE answer to this problem and they are only about $400 more for a set.
 

·
Registered
Joined
·
582 Posts
Personally, I like LB7s a lot. The only con about them for me is their injectors, but like long-time-dmax said, the SAC injectors are really a game changer there. The cost to replace injectors is always going to be higher on an LB7, but with SAC injectors you are going to get far more mileage between sets, should be on par with LLY and on.
 

·
Premium Member
Joined
·
4,545 Posts
Good to know. I'll keep a look out. Still leaning towards the cummins engine. In the perfect world Chevy would have a cummins in it. I love the look and body style of the early 2000s silverados. It's hard for me to get rid of my 2001 gasser.
If you are looking to tow heavy the 6 speed won't be of any real benefit, since most recommend staying out of 6th gear (actually an overdrive) when towing heavy. It does help a bit with the fuel mileage when not towing

The other 5 gears are the same in both transmissions
 
1 - 20 of 30 Posts
Top