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Discussion Starter · #1 ·
So my engine is toast, I'm looking at getting the short block done at a machine shop. What are the "must haves" for this engine. Truck will be tuned, I'm not trying to make 1000hp, just something reliable.

Is a girdle necessary?
Keyed cams and crank? I read this is a must!!! True?
Head studs? I heard the LML doesn't have head gasket issues like earlier models.
All internals will be stock, I plan on replacing the crank, cam, pistons, rod, and bearings, unless you guys chime in and recommend other wise...
ARP rod bolts?
after market main caps?
 

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I don’t have first hand experience, but if I was rebuilding one I would look into getting an alternate firing order cam. That is if you can still find a tune for it.
 

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Discussion Starter · #3 ·
I don’t have first hand experience, but if I was rebuilding one I would look into getting an alternate firing order cam. That is if you can still find a tune for it.
thought that's only necessary in high horse power applications? 'dunno;
 

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None of that stuff is necessary on a reliable daily driver, unless you plan on going high hp/high rpm. Keyed cam and crank, alt fire cam, billet main caps, girdle, connecting rods and arps for the rods aren’t necessary.

Head gaskets are an issue, definitely do studs.

No point in doing new cam and crank unless oil starvation was an issue and they’re scarred.

If I was in your place, I would do throw a set of Mahle Motorsports pistons in it, along with new bearings, head gaskets and head studs. I’m sure the shop would love to sell you the rest of that stuff, but it’s overkill. If that’s your thing, go for it.


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Discussion Starter · #5 ·
None of that stuff is necessary on a reliable daily driver, unless you plan on going high hp/high rpm. Keyed cam and crank, alt fire cam, billet main caps, girdle, connecting rods and arps for the rods aren’t necessary.

Head gaskets are an issue, definitely do studs.

No point in doing new cam and crank unless oil starvation was an issue and they’re scarred.

If I was in your place, I would do throw a set of Mahle Motorsports pistons in it, along with new bearings, head gaskets and head studs. I’m sure the shop would love to sell you the rest of that stuff, but it’s overkill. If that’s your thing, go for it.


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Thanks for your input M.A.M. I'm just trying to get people's opinions. I figured since I'm rebuilding the motor, I should do it right!!!
 

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So my engine is toast, I'm looking at getting the short block done at a machine shop. What are the "must haves" for this engine. Truck will be tuned, I'm not trying to make 1000hp, just something reliable.

Is a girdle necessary?
Keyed cams and crank? I read this is a must!!! True?
Head studs? I heard the LML doesn't have head gasket issues like earlier models.
All internals will be stock, I plan on replacing the crank, cam, pistons, rod, and bearings, unless you guys chime in and recommend other wise...
ARP rod bolts?
after market main caps?

an actual power goal would help but im assuming that your looking for something in the 500 range thats reliable day to day. If that is the case, the girdle is not needed unless your just feeling like doing it. keyed cam and crank would be good, but again depends on your power goals. I would say that if your already having the block machined, may as well have them key the cam and crank, i doubt it will be that much more. LML's do still suffer head gasket failures, though not like the LB7 did, Personally i would do the head studs for peace of mind. I would use LB7 pistons and rods if you can, they are stronger than the LML rods and pistons. I dont think the rod bolt of main caps would make a difference for you one way or the other unless your trying to make bigger power than i am assuming. If the cam and crank are not damaged, i see no reason to replace them. IF you are going to replace them, i have heard the alternate firing order cam reduces the likelihood of a crank shaft failure.

If you could focus on a HP number to shoot for that would help though, If you wanted to make 800HP, some of the things above become needed and not optional.
 

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I don’t have first hand experience, but if I was rebuilding one I would look into getting an alternate firing order cam. That is if you can still find a tune for it.
Can't you just move some pins around in the wiring so tuning doesnt have to be changed?
 

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Can't you just move some pins around in the wiring so tuning doesnt have to be changed?
thats my understanding of how that cam works, you just rewire the injectors to fire in the correct order for the new cam.
 

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Discussion Starter · #9 ·
I’m people are asking for an HP goal. I’d say 600hp, not that I would be running that tune all the time though. I know I can run 600hp with most of the stuff already in the motor.
 

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I agree with Matt, at that power level and assuming nothing is broken internally, I would rebuild the bottom end all stock with the exception of the pistons. The lml pistons are the weak link in the bottom end and are prone to cracking. The Mahles are much stronger, along with a few others.

On the top end , I would have the heads rebuilt and install them with studs and Mahle gaskets. Everything else stock, with the upgrades you have already done, will make for a dependable engine.

I would save the money from the other upgrades discussed and spend it on a turbo.
 
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I’m people are asking for an HP goal. I’d say 600hp, not that I would be running that tune all the time though. I know I can run 600hp with most of the stuff already in the motor.
600 is at the top end of what you can get on stock air and fuel if im not mistaken, but i still think the only thing you need from the list would be head studs. Your still not making enough power for the girdle or billet caps, but if they would make you sleep better at night, dont let me stop you from getting them. To be totally honest i would probably do the girdle even if i didnt need it. I would swap out the LML pistons though, be it for LB7 pistons or the Mahles others have recommended. The pistons seem to be the weak link in the LML engine followed by the rods.
 

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Discussion Starter · #12 ·
Started tearing into it tonight, I don't have a factory repair manual so I'm playing it by ear. Does anyone have the HELM factory repair manual? I want to know if it's worth the money.
 

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I agree with matt 100%. For what you're doing I would skip 90% of your list. Victor Reinz grade cs or get lml golds, arp 425s and some mahle race cast or even delipped lb7 lly pistons would be fine. Theres been plenty of lmls bend rods also but most were running compounds where the torque is instant in the lower rpm range and that's what bends rods. Good tuning plays a huge roll also. It doesn't matter what you do with the crank. Guys buy 5k dollar ones and they still snap. Stock cam will be fine also. The alt fire ones havent proved to be the fix all like people hoped.You can still get delete tunes from very good and highly reputable tuners its who you know.
 
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Discussion Starter · #14 ·

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It burns off. Check around for short blocks.Call dan at ppe he had very reasonably priced short blocks a little awhile ago. I believe his had carrillos in it and mahle race cast.
 

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Started tearing into it tonight, I don't have a factory repair manual so I'm playing it by ear. Does anyone have the HELM factory repair manual? I want to know if it's worth the money.
i would get a single vehicle DIY subscription to alldata, its like 50 bucks or something for a couple years of access.
 

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Discussion Starter · #17 ·
i would get a single vehicle DIY subscription to alldata, its like 50 bucks or something for a couple years of access.
Thanks, I actually did this last night. It was like $30 for a year.
 
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Discussion Starter · #18 ·
Quick update, cut open the oil filter and this was at the bottom, filter paper element also has lots of metal... Motor is coming out Tuesday.
 

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Discussion Starter · #19 ·
Not sure what engine failure I had until I take it a part. I will update after I get it out and taken a part. I was on a tow tune so the transmission would learn, then the truck started knocking. Not sure if it was a tune problem or a mechanical problem...
 

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Discussion Starter · #20 ·
Sorry too many post to keep track of LOL so the crank shaft broke and most of the push rods are bent. Piston and rods look ok. Trans, heads and driveshafts are out for rebuilding.
 

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