LB7: Looking to get an LB7

[hetzler_l33]

You're right zak, but what engine/truck doesn't have quirks? They're all unique in their own way. I agree on the body style, I love the front end on the 01-02 Duramaxes. I haven't heard anything else bad about the LB7 except the high injector failure rate.

I've driven an LLY, LBZ, and an LB7 in that order. The LB7 drive the best imo based on response and smoothness. The LLY was used as a contractor truck at one point which raised questions but the price was too high for its 226k miles (19,700). The LBZ was a one owner, local, and it actually looked horrid on the outside from it's dents. Only had 119k miles but with a price of 25 Gs I passed since most of the dents weren't going to buff out lol. Then the LB7, probably the best overall condition out of the three. 2wd or 4wd doesn't matter a whole lot to me right now as I have my 05 Z71 if I need it.

Overall, you're right and I agree with everything you're saying zak. The price is high and the unknown history makes me very uneasy.

TheBac, the LBZ has had a few piston issues iirc, maybe it was the lmm. Idk, either way anything from an lmm and up is out of my price range but for my first diesel I think an LB7 would be good if I can find one with a noted history or can talk to the previous owner. I've heard about SAC injectors but there are skeptics who say it won't make a difference. I've also read about people swapping LLY heads on their LB7 block, not sure about the outcome or if it solved anything.

As for the task of doing an injector job, I can manage with a weekend and a friend. The work is not a problem for me, but the money on the other hand is what I'm worried about. I don't mind doing it once but if they repeatedly burn at a rate of 20-50k miles it's going to be an issue. I hear my friends telling me to not buy an LB7 because "they're junk" and that's coming from LBZ and LMM owners. Like I said before, I prefer the drivability of an LB7 over the rest and it's a good first diesel.

I'll look into that Josh, I appreciate it. I'm curious why you say a 2wd diesel is worthless?


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[Burn Down]

You all need to remember injectors and the fuel system in general are wear items... Meaning all will fail eventually. Lilly's are getting up there in age, which is why you are seeing more injector issue questions starting to pop up on the LLY, LBZ's will be next and so on. Anyone who purchases a High Pressure Common Rail Diesel especially and older one better have some money set aside for maintenance repairs fuel system, head gaskets, trans issues etc etc.

 

[joshd472]

They're too heavy. You literally can't back up a dry hill of the grade is steeper than 5%. A good example. I stopped to help a broken down hard body Friday. Where I pulled off the road was kinda sandy. Once I got the hard body running he took off. I had to put my truck in 4wd to get out.

You don't have to go off-roading to get stuck. I pulled my wife's car out in the yard the other day to wash it then put it back in the garage. Pulled my truck out there to wash it. I had to put it in 4wd. I'm running 12.5 mt tires too.

 

[zakkb787]

Just think. 500+ lbs of torque going to one or two tires with the least amount of traction possible. Makes for nothing but a road queen. LBZ and mom both have the piston issue. Lb7 are far from junk. Buy QUALITY REMAN injectors and you'll have them last for a while

 

[hetzler_l33]

Those are some pretty valid points, didn't really think about the hill grade affecting it that much. I'm just used to my 1500 hahah. I know the LB7 are not junk and like I said before, I prefer them over the other models. The only thing I wish the LB7 had was a VGT but I'm sure they make one you can put on, it'll just have to have its own controller/ECM.

That's true Burn Down, I didn't think newer designs would wear out as much as the LB7 since they have the injectors outside the valve covers.

I'm going to look around some more and see what's out there, maybe give it some more time as well and a good deal might pop up. 01-02 LB7s are pretty rare to come by here, the 03 & 04 are the main ones I see with them being $12-15k usually. Most have right at 200k miles so I'm going to find one I can actually read the history on or talk to the previous owner.

Any truth that if you tow heavy with the LB7, the injectors will burn up faster?


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[zakkb787]

Those are some pretty valid points, didn't really think about the hill grade affecting it that much. I'm just used to my 1500 hahah. I know the LB7 are not junk and like I said before, I prefer them over the other models. The only thing I wish the LB7 had was a VGT but I'm sure they make one you can put on, it'll just have to have its own controller/ECM.

That's true Burn Down, I didn't think newer designs would wear out as much as the LB7 since they have the injectors outside the valve covers.

I'm going to look around some more and see what's out there, maybe give it some more time as well and a good deal might pop up. 01-02 LB7s are pretty rare to come by here, the 03 & 04 are the main ones I see with them being $12-15k usually. Most have right at 200k miles so I'm going to find one I can actually read the history on or talk to the previous owner.

Any truth that if you tow heavy with the LB7, the injectors will burn up faster?


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Vgt on an lb7... you're defeating the purpose :roflmao:there are a few that have done it but really the only way to do it 100% right is a full LLY swap. I love driving a fixed vane turbo tho. I've never heard they go out faster if you tow heavy. And it's not the fact that they're outside the valve cover. It's the injector design itself that's flawed.

 

[DAVe3283]

The injectors don't go out faster if you tow. It mostly appears to be luck of the draw. There is some indication that short in-town trips wear them out quicker, but I'm not sure that's the case.

As for the SAC injectors solving everything, I'm one of the skeptics... but I also installed SAC injectors. I'll believe they last longer once they do. So far, no one has had them fail, which is a good sign. I have a thread on here detailing how they are holding up for me. So far, so good.

And really, if you're so hard up for money that you can't afford the injectors in a LB7, you should save up until you can before you buy one. They WILL go out eventually, and you want the money set aside. If you want a cheap, low maintenance, reliable truck on the cheap, a LS powered truck might be what you want. The diesel only makes financial sense if you tow a lot. Otherwise, just realize you're paying a premium to be able to bomb over hills with a trailer.

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[hetzler_l33]

The injectors don't go out faster if you tow. It mostly appears to be luck of the draw. There is some indication that short in-town trips wear them out quicker, but I'm not sure that's the case.

As for the SAC injectors solving everything, I'm one of the skeptics... but I also installed SAC injectors. I'll believe they last longer once they do. So far, no one has had them fail, which is a good sign. I have a thread on here detailing how they are holding up for me. So far, so good.

And really, if you're so hard up for money that you can't afford the injectors in a LB7, you should save up until you can before you buy one. They WILL go out eventually, and you want the money set aside. If you want a cheap, low maintenance, reliable truck on the cheap, a LS powered truck might be what you want. The diesel only makes financial sense if you tow a lot. Otherwise, just realize you're paying a premium to be able to bomb over hills with a trailer.

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Gotcha, well money isn't a problem unless it keeps burning out in a short amount of time. I have an LS based engine right now, it's the L33 HO in an 05 ECSB Z71 and I've had it for a few years now. It's my first and only truck, but I love it.

Just looking to expand my horizons beyond the gas motor and try a diesel although I'm keeping my L33 as a back up or DD

 

[hetzler_l33]

Vgt on an lb7... you're defeating the purpose :roflmao:there are a few that have done it but really the only way to do it 100% right is a full LLY swap. I love driving a fixed vane turbo tho. I've never heard they go out faster if you tow heavy. And it's not the fact that they're outside the valve cover. It's the injector design itself that's flawed.

I just like the different options and more potential you have with the variable vane turbos but driving-wise, the fixed vane is the best imo. Best response when I hit the pedal vs the VGTs in the LLY and LBZ.

Well some guys on the forums said that towing heavy will cause them to burn out faster but there's so many theories as to why that it can be whatever you want it to be really. Like Dave said, it's just the luck of the draw. I've heard that too and I'm sure that's why so many people have faith in the SAC injectors since they use a single nozzle/opening design vs the multiple nozzles on the GM and Bosch ones.

How long have the SAC injectors been out? I haven't heard much about them around here and also haven't heard of them failing on the forums so it must be newer. For the price I hope they don't fail as much. Would a retune be necessary for even a 45% over SAC injector? I'm assuming so but I'm not an expert

 

[joshd472]

VGT have better throttle response......

 

[DAVe3283]

How long have the SAC injectors been out? I haven't heard much about them around here and also haven't heard of them failing on the forums so it must be newer. For the price I hope they don't fail as much. Would a retune be necessary for even a 45% over SAC injector? I'm assuming so but I'm not an expert

SAC injectors have been available for the LB7 for about a year. I have one of the early sets, only a month or two after they came out. The SAC-style tips have been around much longer, though. It is the factory style for LLY and newer.

I would recommend a retune for a SAC injector. The way they respond to rail pressure and timing is totally different than stock, and the stock tune won't run too well with the SAC injectors.

 

[zakkb787]

I'm honestly gonna have to agree with the op with this. The LLY is laggy. And my lb7 vs my dads deleted 6.7 Cummins (I know it's apples to oranges) but my truck spools a lot faster and lots better response. That's why the lb7 feels so much different than the others. But again. My opinion.

 

[hetzler_l33]

Found out some information regarding the LB7:
An older gentleman owned it since new in 2002
No injector work done on it, injector pump was replaced a couple years ago
Owner is a professor in East Mississippi as a diesel instructor
Guy I talked to said he knows him, he maintained it really well but he did say he only pulled his camper with it so nothing crazy.

Overall, it's the best Dmax I've looked at condition wise but if they'll lower the price to 9.5k I'll probably buy it.

I'm going to set up another test drive and I'm going to check the oil for fuel contamination after it's warmed up and I'll check the radiator hoses for any pressure concerning cracked cup or head gasket although the reservoir is clean with no soot.

Didn't see any fluid on the ground but I'll double check. Seems like it's been a good truck with an easy life and has been well maintained. Anything else I should look for or test?