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I just bought an LLY...

If you are towing, do not use a power tuner until you remedy the intake/induction tract (junk). You stand to blow a head gasket, probably somewhere around 6800 ft elevation, far from home. "Induction Overhaul" should be first on your list, followed by a smart intake that dampens IAT rise when the fan comes on. Most aftermarket intakes fail at this very important step.
 
If I go to the dealership to get a reflash for the cd player, should I wait till I get the lbz mouthpiece installed? And when I do the lbz mouthpiece, since I'll be checking with salvage places, should I see if I can get the airbox too, and just replace the whole system with the lbz induction system? I checked the S&B and saw that it was just the airbox, but doesn't have the mouthpiece, so I'll make the mouthpiece the priority.

As far as manuals, I see a helms full service manual for a silverado sierra/sierra denali (http://www.helminc.com/helm/Result....005&Category=&Keyword=&Module=&selected_media= ) but I don't know if that includes my truck. There is also the option of Alldatadiy - https://checkout.alldatadiy.com/adecomm/diyecomm/checkout?execution=e2s3 - which is cheaper, but I don't know which of the 2 would be the best. I like the idea of a hard copy, simply because I like the option of having info available w/o internet. If alldatadiy is an option, tts and duramaxdiesel would probably be just as good, if not better...

I think I'm going with the Edge Insight CTS and the Diablo Predator U7185. Just to clarify, but the predator is similar to the superchips I had for my 24 cummins, where you plug it into the OBDII port to change the settings, and then unplug it. You don't actually drive with the predator plugged in, right? Because the Edge Insight has to be plugged in. Both the Insight & Predator can be updated online too.

For the egr delete, I'm looking at creatures of the night performance website and there are so many egr delete options (a tube, plate, cap, and delete plate) - what's the difference between them all? And he has intake/boost parts on the same page as the egr, too. I guess my question is, soooooo many choices, how do I know which one I should choose? It was suggested that I do my egr when I do the FPR, but I'm hoping that a new fuel filter + trans fluid will clear that up and I won't have to do it. If I do, do I have to purchase the new FPR from the stealership, or get it from someplace else? (for the additional viewers of this - Warwagon's fpr KISS write-up: http://www.thetruckstop.us/forum/sh...FPR-install&highlight=fuel+pressure+regulator) Also, where do I get at heavy throttle spring?

There is an exhaust place in town that sells MBRP exhaust, and I think I might get a price check on duals w/o cat or muffler. What's the safest minimum size I should go with exhaust, whether its duals or single (4"-?")? (Also, would it be safer to get a single exhaust for the duramax? Because I never see dual exhaust for diesels, unless it's stacked...)

I plan on doing the HOOT method & probably a coolant drain when I get the Predator, but not before...unless it's advised after all the filters are replaced. That way I can get more familiar with the truck and also save up a little for everything. And I'm planning on doing the mouthpiece, than either the Insight and/or exhaust, than predator. I don't want to be pumping more power if it can't breath.

As far as if its cloth or leather, its leather. Heated leather seats & automatic controls up front. All the comforts inside. Way down the road, I may go searching for a middle seat and check around for leather upholsterers, since there's no such thing as a leather front middle seat...it'd have to be a custom item. Also looking into the roll-out toolbox that sits in the bed of the truck (4' x 6') - then I can keep my tools in the bed, but still have the full length & width of the bed. I'll just lose 8-12" of height...I think.

I'll try and post some more pics when I get a chance.
 
If I go to the dealership to get a reflash for the cd player, should I wait till I get the lbz mouthpiece installed? Doesn't matter but checking for the idle surge reflash at the same time is a good idea And when I do the lbz mouthpiece, since I'll be checking with salvage places, should I see if I can get the airbox too,Both and just replace the whole system with the lbz induction system? Yes I checked the S&B and saw that it was just the airbox, but doesn't have the mouthpiece, so I'll make the mouthpiece the priority.

As far as manuals, I see a helms full service manual for a silverado sierra/sierra denali (http://www.helminc.com/helm/Result....005&Category=&Keyword=&Module=&selected_media= ) but I don't know if that includes my truck. There is also the option of Alldatadiy - https://checkout.alldatadiy.com/adecomm/diyecomm/checkout?execution=e2s3 - which is cheaper, but I don't know which of the 2 would be the best. I like the idea of a hard copy, simply because I like the option of having info available w/o internet. If alldatadiy is an option, tts and duramaxdiesel would probably be just as good, if not better...
I wouldn't spend the $ right now. You've got plenty of online help

I think I'm going with the Edge Insight CTS and the Diablo Predator U7185. Just to clarify, but the predator is similar to the superchips I had for my 24 cummins, where you plug it into the OBDII port to change the settings, and then unplug it. You don't actually drive with the predator plugged in, right?Right. The tune is loaded and then the unit is unplugged. Because the Edge Insight has to be plugged in. Both the Insight & Predator can be updated online too.

For the egr delete, I'm looking at creatures of the night performance website and there are so many egr delete options (a tube, plate, cap, and delete plate) - what's the difference between them all? And he has intake/boost parts on the same page as the egr, too. I guess my question is, soooooo many choices, how do I know which one I should choose? For now I would suggest a blocker plate and Finger stick (because you aren't going EFI right now). I know you can get them fromAll Seasons if Henry (Creatures...) doesn't have them.It was suggested that I do my egr when I do the FPR, but I'm hoping that a new fuel filter + trans fluid will clear that up and I won't have to do it. If I do, do I have to purchase the new FPR from the stealership, or get it from someplace else? (for the additional viewers of this - Warwagon's fpr KISS write-up: http://www.thetruckstop.us/forum/sh...FPR-install&highlight=fuel+pressure+regulator) Also, where do I get at heavy throttle spring? I would not plan the FPR replace unless you are SURE you need to.
There is an exhaust place in town that sells MBRP exhaust, and I think I might get a price check on duals w/o cat or muffler. What's the safest minimum size I should go with exhaust, whether its duals or single (4"-?")? (Also, would it be safer to get a single exhaust for the duramax? Because I never see dual exhaust for diesels, unless it's stacked...)I'd suggest MBRP 4 or 5" single

I plan on doing the HOOT method & probably a coolant drain when I get the Predator, but not before...unless it's advised after all the filters are replaced. That way I can get more familiar with the truck and also save up a little for everything. And I'm planning on doing the mouthpiece, than either the Insight and/or exhaust, than predator. I don't want to be pumping more power if it can't breath.

As far as if its cloth or leather, its leather. Heated leather seats & automatic controls up front. All the comforts inside. Way down the road, I may go searching for a middle seat and check around for leather upholsterers, since there's no such thing as a leather front middle seat...it'd have to be a custom item. Also looking into the roll-out toolbox that sits in the bed of the truck (4' x 6') - then I can keep my tools in the bed, but still have the full length & width of the bed. I'll just lose 8-12" of height...I think.

I'll try and post some more pics when I get a chance.

Some opinions above in red. I wouldn't do too much of anything all at once Forest. Get used to it first and then you'll be able to pick out what's really needing to be addressed. PM is one thing, modifying for performance is another, and then there is throwing expensive and labor intensive fixes at it because you THINK it might be needed...If you have a FPR problem then yes, do the EGR delete at the same time but wait to see if you need to.
 
Alright, thanks! Mike - any specific reason to stick with a single exhaust? (Just curious, that's all.) According to MBRP - it sounds like I could install the exhaust myself? Which sounds good to me, haha.

And when you say a finger stick, are you talking about the tube? Nevermind, I think I figured it out: http://www.duramaxforum.com/forum/how-tos-diy-write-ups/103865-how-lly-egr-delete.html . The plate is for the tube near the firewall. The finger stick (tube) is for on top of the motor, and it appears I need to purchase some heater hose to reroute the heater line?
 
If you are towing, do not use a power tuner until you remedy the intake/induction tract (junk). You stand to blow a head gasket, probably somewhere around 6800 ft elevation, far from home. "Induction Overhaul" should be first on your list, followed by a smart intake that dampens IAT rise when the fan comes on. Most aftermarket intakes fail at this very important step.

Just to give you an idea how bad GM pooched this one: AFE made a copycat replacement mouthpiece - one of the only engines this was ever NEEDED for, GM came up with a retrofit/overhaul including a source for cold air, and Killerbee offers one of the original kits (cold air, machined mouthpieces, and the improved GM part adapted to the factory airbox, modded factory airboxes, etc.) and ideas for this. The paper he wrote explains why the LLY gets hot from this design flaw. Even if you don't overheat removing the restrictive mouthpiece gets you better SOTP feel, turbo spool, and MPG.

http://www.maxxtorque.com/dieselcommunity/summer-2008/duramax-lly-overheating?showall=1

You will need your propeller hat for this one:

killerbeeperformance-dot-com/lly-overheating/thermal-feedback/thermal-feedback-loops-in-turbocharger-applications

I towed a toyhauler through Death Valley 117 degrees -200' to 8000' with no more than a mouth piece replacement. I didn't hit the overheat alarms, but, I wanted my 1993 as at least it could have run the AC at 30 MPH! The engine will hit 4800 RPM during grade braking. :eek:

Since then: I run the Killerbee tune with the turbo brake over 2800 RPM, methods to stop thermal runaway, and a bump in HP. I also sealed the airbox to the fender after some sawsall work.
 
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Just to give you an idea how bad GM pooched this one: AFE made a copycat replacement mouthpiece The AFE mouthpiece is NOT a direct copy of the LBZ mouthpiece. It is very simliar yes, but is a cast aluminum piece VS the LBZ's plastic design. And it is a bit higher flowing which most don't need. GM quickly discovered that the extra large LBZ mouthpiece wasn't neccesary as the LMM uses a smaller mouthpiece than the LBZ. - one of the only engines this was ever NEEDED for Not all LLY's overheat, so it is not NEEDED, GM came up with a retrofit/overhaul including a source for cold air, and Killerbee offers one of the original kits (cold air, machined mouthpieces, and the improved GM part adapted to the factory airbox, modded factory airboxes, etc.) and ideas for this. The paper he wrote explains why the LLY gets hot from this design flaw. Even if you don't overheat removing the restrictive mouthpiece gets you better SOTP feel, turbo spool, and MPG.

http://www.maxxtorque.com/dieselcommunity/summer-2008/duramax-lly-overheating?showall=1

You will need your propeller hat for this one:

killerbeeperformance-dot-com/lly-overheating/thermal-feedback/thermal-feedback-loops-in-turbocharger-applications

I towed a toyhauler through Death Valley 117 degrees -200' to 8000' with no more than a mouth piece replacement. I didn't hit the overheat alarms, but, I wanted my 1993 as at least it could have run the AC at 30 MPH! The engine will hit 4800 RPM during grade braking. :eek: What's wrong with hitting 4800 to slow you down if it saves you from overheating your service brakes? The engine was designed to do this just for this reason.

Since then: I run the Killerbee tune with the turbo brake over 2800 RPM, methods to stop thermal runaway, and a bump in HP. I also sealed the airbox to the fender after some sawsall work.

Not trying to be an A$$, but I don't want you to scare the guy either as this is his first DURAMAX. If you listen and read everything on these forums you will swear that they are all ticking time bombs, when in reality you normally only hear about problems on these forums and not the countless rigs that never give a hiccup of trouble. The biggest reasons for the LLY's that did overheat was poor tuning on GM's part to comply with the added emissions systems. The LB7's did not suffer from the problems that some LLY's did because it didn't have all the emissions crap on it. The LLY is a great engine I think, and IF I was in the market it would be at the top of my list as so many people have been scared off from them by reading the forums and seeing the problems that SOME experience.
 
LB7 or LLY Bud?
How are you getting around the egr DTCs? The usual reason for the Finger Stick?

My LLY never threw codes or gave a CEL when I blocked the EGR.

Also, I have towed hot and heavy, and have never had an overheating issue. The fan came on a time or two when the truck was still stock, but nothing since I made exhaust and intake modifications and ran a decent tune (first the Predator and now the PPE Hot +2 ET).
 
Some seem to throw codes and others don't. I know that I just did a tune for somebodys DURABURB and he said his EGR had been blocked for 3 months and never threw a code, yet others will pop a code if you change the exhaust.
 
Not trying to be an A$$, but I don't want you to scare the guy either as this is his first DURAMAX. If you listen and read everything on these forums you will swear that they are all ticking time bombs, when in reality you normally only hear about problems on these forums and not the countless rigs that never give a hiccup of trouble. The biggest reasons for the LLY's that did overheat was poor tuning on GM's part to comply with the added emissions systems. The LB7's did not suffer from the problems that some LLY's did because it didn't have all the emissions crap on it. The LLY is a great engine I think, and IF I was in the market it would be at the top of my list as so many people have been scared off from them by reading the forums and seeing the problems that SOME experience.

Point taken. He has already purchased it and like many new 6.5 owners needs to know the ins and outs of it. A great engine backed by the toughest auto transmission made for a pickup that GM left a lot of power on the table for the aftermarket to 'find'. The aftermarket solutions for the LLY are the only reason I even considered buying one.

After making changes over the past year or so to my 2005 I would take it long distance before my 6.5's. The worn out FPR (idle surge) and intake were my first mods followed by a tune and throttle springs. mainly due to it's signature touchy throttle. Nothing urgent needs to be done to a 2005.

Nothing wrong with using 4800 RPM to slow you down - I did not say and should have that some people get nervous running an engine that far in the orange on the tach. No reason to get nervous as it is the 'no load' RPM that is higher than the loaded RPM. So the checkered, orange is a grade braking RPM only. It is something else to see a diesel scream at near 5000 RPM while going down a long mountain grade. (I have had passengers panic over high engine RPM before. During the long downgrade with hot brakes is not the time to hold that discussion as you are busy driving.) Doing a turbo brake in the tune helps. The 2005 is the first Duramax year you can do it in the tune without an add on expensive exhaust brake.
 
I will say that I never had any temperature troubles with my LLY in the 55k I had it. I only traded to get more truck for a lower payment when GM had the 3 day deal of 0%-72mo in mid '06. Never regretted it...

BTW Forest, a PCV reroute kit would be a real good addition as well. Will keep your intake MUCH cleaner.
 
Alright, so after I took a look at the motor compartment, I understand a little more of what I need to do.

Anyone know what size the fuel filter nut or WIF is?

Also, can the egr be plugged under the tube instead of near the firewall (temporarily and would it make any difference)? Also, I can understand the delete plate for what's near the firewall, and the tube that will connect on top, but what about the piece under the tube? And the huge electrical plug that plugs into it? (I mean, I understand the fingerplug(?) replaces something in there...but that plug that's in the end of the egr system looks rather complex... (I sure hope you guys know what I'm talking about)

Also, what's the purpose of the top plastic boxy thing, that elbows off of the mouthpiece?
 
Oh, and I checked with the dealership about a reflash, and he said it'd take about an hour for the cd player and about an hour for the idle surge, and they charge 102/hr... I think I'll wait for 2 tank fulls. :)
 
Nost charge an hour for a flash even though it takes em a whopping 10 minutes tops to do the actual work. The fingerstick is not something tht installs in the EGR valve, but rather a fooler of sorts that tricks the ECm into thinking the EGR is flowing when in reality it isn't. You need to install the blocker plate in the exhasut up pipe before the EGR cooler, and then wire in a finger stick(although some trucks don't code without a finger stick installed). And that plastic box on top of the engine is a resonator, it is there to quieten down the turbo noise.
 
05 backseat.jpg05 vin tag.jpg05 underbody after chipped-b4 washed.jpg05 mouthpiece base.jpg05 inside.jpg05 gooseneck.jpg05 glovebox camper.jpg05 engine compartment.jpg05 detailed glovebox list.jpg05 behind seat.jpg511173048_15_b.jpg

Few notes about these pics. I got most of my cab tools back in the cab, so that was nice. One picture is of the base of the mouthpiece which is rather filthy... Uh, gooseneck hitch is ~6" in front of the center of the rear axle...I thought it was supposed to be right on top of the axle...? Uh, the underbody of the truck is after I chipped off most of the dirt, but you can still see caked mud residue. Um...oh, and the fancy front grill...I think I might remove. Not a huge fan. But then again, I've never been a huge fan of all shiny stuff, haha.
 
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