I've come across a pretty good opportunity to trade my 04 LB7 for a new LLY. My question is to all the people that have traded up. Did you like your LB7 better or are you happier with your LLY? My 04 has been great so far, the dealer only sees it drive by every once in awhile. ):h

I would have to say I like the new motor better. #1 injector replacement, new truck 1-2 hours, old truck 1-2 days. #2high idle #3more hp 310 and ft 590 #4 32 bit over 18bit processer = new truck you stomp it goes ,old truck you stomp 3 sec. later then it goes. Only negitive side is cat and EGR. Iv straight piped mine NO cat no muffler and it performs WAY better, and there is a way to defeat EGR just seach for it on this site. So over all ya go for it, personaly I love my truck and would recomend it for anyone. Just my 2cents hope this helps you.

As long as you don't plan on BIG HP you will like the LLY. You will also get a bit less fuel mileage with the LLY. Not huge but you will lose a mpg or two.

All in all it's nice to know if you do have a injector problem you likely won't be down for a week or more.

It's a PITA switch stuff over so take that into consideration as well.

One other thing, I would personally chose to wait for the sunroof.

I would keep my 01 lb7. Even with it on its third set of injectors it ran and sounded a hell of a lot better than my LLY. The clattering noise this one makes is driving me up the wall. All my friends have asked whats wrong with the engine and you can hear the clatter over the radio!

Steve

swatkins have you had the calibration updated yet?

Had it done two weeks ago. Still the same and the dealer says it is normal for this engine... It really is a shame, such a nice truck and its engine sounds like a 13 year old designed it :(

I would keep my LB7.. I had the opportunity to trade up to a 05 CC Dually LLY this part week and turned it down. As much as I wish I had a dually now I decided against it.. I like the motor in my truck. No problems (knock on wood) as of yet...

My engine doesn't sound any worse then my LB7 did. It sounds like there might be something wrong with yours.

I have a 04 lly with 11k and sofar been very smooth, no rattle, clattering, and has not been reflashed. Many have commented on how quiet it is compared to other diesels the've been in. Mileage could be better but 18-19 at 70 (level road and no wind) isn't bad. Overall mileage 30% towing 5er, 40% short trips and 40% highway is 13.5.

I agree with Max Power, the dealer hasn't found the problem yet. I'm sure most lly owners would say their duramax is very quiet.

Ditto on mine being very quite!

Just traded upto a 05 GMC LLY and I love it!!! The motor is quieter by alot,it's smooother in operation,and has alot more power. My my old 03 duramax was a slug compared to this truck. Granted the truck cma eto life when I chipped it):h I can't wait to get the edge for my LLY):h

I have an 02 lb7 cc sb4x4 with 110,000 miles on it. ran an edge box no attitude for 100,000 of those miles. I tow 50% of the time. never had anything but normal service done ( trans fluid filter change 5 times) .Just bought an 05 lly LT cc swb 4x4 with elec sunroof and rear entertainment sys. Nice truck nice features big improvement feature wise, but it ssure feels like a family diesel to me. I added an edge attitude and its better except for the hitches with the edge and the lly . the mileage is better with the 02, the is alot better the 02 . leave to the EPA. dissapointed !

I appreciate the responses. I really like my LB7. A buddy has a LLY and it sounds like it has central vac in it when it's idling. Dumb egr. As for what Max Power said, I wish it had a sunroof. As for the BIG HP, there probably isn't too many people here that planned on big HP when they bought their truck. It just seems to happen when you hang around here for awhile. This is by far the most expensive web site I have ever seen.

A note to the moderators: If the wife tries to change my password so I can't play here anymore, don't let her.....

My LLY is much quieter than my partners LB7. His sounds like mine when my pilot injection cuts out.

i agree with swatkins, keep lb7. my 05 at 75 cruise control on basic nuetral load absolutely hammers. truck made in 07/04. no reflash. about half afraid to have dealer fool with it. much louder than my 01 ford. at these perameters. excellent truck otherwise. it is embarassing to have to explain all the noise. i can control it by not using c. control and feathering the throttle from no load to slight load. some ford people had good 6.0 before reflash. guess i will have to risk it.

nelson j/a 05 chev.

jetboat, get the reflash. There is no reason not to and it should solve the problem.

i believe you are correct max. i purchased truck not from local dealer but 90 miles away. just not been back. some ford friends had reflash ruined mileage and performance. an old thread indicated oil related problem with dmax tick. some would tick and some not so i have lived with it. it is a weird problem, does not always manifest itself. usualy only after 50 or so miles. i guess i will pull the edge and take it back to the dealer, i just do not like someone fooling with my machinery and i donot have the expertise to do it myself. oh well thanks for the advise.
nelson.

Do the reflash,helped my truck

Sold 02 with 73,000 miles that had all injectors replaced at 70,000 because new injectors were easier to replace and I go so out of the way places in Central America. VERY STRONGLY REGRET IT!! 02 was best new truck I ever owed, and I've owned a few GM diesels (see signature). 05 is nice truck, but gutless, terrible fuel mileage, and not the mechanical package the 02 turned out to be for me. Keep you LB7!

EGR defeat is right here: http://dieselplace.com/forum/showthread.php?t=15231&highlight=finger+board

Thank Fingers for that one.


Tom

Question from a newbee, why are people saying that the LB7 engines are more powerfull than the 05 LLY? Isn't the HP and tourqe ratings higher on the LLY vs. the LB7 ?

Note:
I have not driven an LB7 just my 05 LLY and I am very happy with it.

There are more boxes, injectors etc out there for the LB7. The LLY in stock form is slightly more powerful then an LB7. With an LB7 you can get almost 500hp with one programming option. With an LLY it is hard to get over 400hp with one programmer.

Thanks for the info Max.

This thread gives me a case of deja-vu. Back in '98, right about this time of year, I was ordering a new Dodge CTD. Back then, there was the big 12 vs. 24 valve debate with the new ISB. Poor power, MPG, noise, etc., were the common complaints. Reflashes were rumored to make things worse/better.

Fast forward to today. I have an order in for a LLY, supposedly to be built the week of 12/13. Am I nervious, yes and no, as I've been there before, and I know what a great truck the '99 ended up being!

At least I won't have to worry about the tranny! ):h

;) To the point: LB7's had issues, not just injectors, from inception through 2003. LLY's will be no different. Given the option I went with the new technology and improvements and will begin my LLY fixes much like the LB7 owners did.

Aftermarket programmers/tunes are coming out for the LLY's and the hp/tq numbers are climbing. If you increase too high you'll need to have the tranny upgraded. The Allison is one fine tranny, especially when towing my 40' 16k lb toy hauler. With a dually I hardly know it is back there.

Good luck! Several polls on the LLY show a 90%+ favorable experience with them. JJ :)

Sold 02 with 73,000 miles that had all injectors replaced at 70,000 because new injectors were easier to replace and I go so out of the way places in Central America. VERY STRONGLY REGRET IT!! 02 was best new truck I ever owed, and I've owned a few GM diesels (see signature). 05 is nice truck, but gutless, terrible fuel mileage, and not the mechanical package the 02 turned out to be for me. Keep you LB7!
Almost identical situation for me and right now I feel the same way. I miss my 02, from the hood, to the motor. My LLY pings so bad at cruise it drives me crazy, I can't leave my Edge on during warm up, and my MPG plain sucks compared to my old truck. It is in at the GMC House today (hopefully) getting the reflash and which I hope fixes my compaints.

With that said I am not ready to jump ship yet. I agree JJ and hope with time this one will turn out to be another "best truck I have ever owned."

Stock for stock empty, the LB7 will smoke an LLY truck, light to light. An LB7 truck will feel and sound more powerful in cab (could be just different sound). This hard to admit if you just spent the big bucks (me too), but if you are really honest with your self you will have to admit it. Read your original posts just after purchase and everyone that was a previous LB7 owner sheepishly asked if there was something wrong with thier truck. A 14% to 15% increase in torque, should be measurable and felt by the driver ( I could in the other brands)! The new tires and suspension parts (tight truck) was probably the best part of the new ride sensation, not the new power. Dynos have shown that the LLY does not make more power in the driving range. In fact I have been told it makes less useable torque (not much less so that would not be felt). If that is not true then, where are the glowing dyno reports for bragging rights like on the other brands sites. Compound that with, overheating, surging, pinging, and BS about dirty fuel causing injector failures (I was told I might have to pay for the new injectors on a 2400km old truck because of dirty fuel, lucky for me it did not cure the LLY problems), I think GM does not really care or know how to cure these problems because the trucks are used over a wide range and the different problems happen to different user groups (divide and conquer). I have read that someone was told this cure was coming from GM for this issue, that for that issue, many times. Where are they. Anybody hear anything new? If we look at the facts, the 1000 series Allison, is rated for 520 ftlb. of torque from Allison. I do not think GM will put 605 ftlb. torque into it (might cost them some money in warantee eh!). I do not think we will see the true LLY till the tranny is upgraded. I also think GM will not waste any more money trying to cure the existing problems in the current LLY package because the next one is finished or close to it. GM should thank us for helping with the research and developement of the LLY by offering an extra special trade in value when the new package comes out (but I will not hold my breath). They all do it, that is why big business never loses. For me this truck will do just fine for the next 12mons. untill it is time for a new one then somebody else will deal with these issues but will have lower expectations because it is used and the aftermarket will be happy to solve them for a couple of bucks. The internet does not blow them out of proportion if you keep track of the posters name and apply some math. In fact, the % of problems is probably less because the site posters are usually knowlegable enthusiasts who can cure some things themselves. This theory is from years of internet forum reading when researching a purchase, I just let my little head make the decision on this purchase. Thanx Geo

I never drove a new LB7, but drove an '02 with 70,000 miles on it before buying my '04 LLY. Seat of the pants I couldn't tell much if any difference in performance. The LB7 was much louder in the cab, but did not ping like my LLY. Honestly, I didn't know what the mechanical differences were between the two motors until after I bought my truck. Now that I know, I still would have sought out an LLY simply because I'm not comfortable with the injector setup in the LB7. Other than the pinging, I'm very satisfied with my LLY.

I traded up from an 02 and am very pleased. It has about 15,000 on it now. It is defently much quiter than the 02 and seems to park easier with a quicker turn. I am very happy and would do it again. If your lly is loud you should insist on seeing a factory Rep. as there is something wrong. Mine has not been reflashed yet.
Durabill

After a test drive in a friends LLY I have this to conclude.
The LLY has some meaningful evolutionary changes made to it. (injector location/VGT) that are fantastic ideas.

BUT in a bare knuckles dragrace him total stock (me with 4" and AFE all boxes and modules off) same truck config (we both had full tanks of fuel as well) the end result was the LLY lost by an insignificant margin. We switched trucks for a day (in stock configuration)
IMHO BUILD QUALITY on the truck is better on the new versions, suspension crashing, tramlining, tors stiffness were significantly better.
As far as powertrain.... I think GM could have waited another few months to release the LLY. I expected more, and if i did not own an LB7 i would be ignorant of the changes good or bad. GM will get the new LLY programming right, but when? And you can bet your heiney that their base maps will respect the EPA guidelines to protect the EGR .

Having said that, In looking at the whole pic, build quality, powertrain execution, MPG (which is why I bought a **** Diesel in the first place) I have decided to keep my LB7.
Given the trade in value for the old VS buying the new truck, I personally can't convince myself to 'upgrade'.

The LLY I drove is a good truck, but I think I will keep my DMX LB7 until the wheels fall off.

I'm on my 3rd Duramax. My 2004 is the new upgraded motor. It has more HP and my fuel mileage is very good. The advantage with the new motor it will be alot easier to service! That's my 2 cents! :cool:

Does anyone have a dyno run on a stock LLY and LB7 to compare (rear wheels) (Mr. Kennedy?). I for one do not believe the claim of peak torque at 1600 or the 590ftlb. The 555 Cummins I just had was way more believable. Please show torque and horsepower curves. Thanx Geo.

I donot regret buying this truck. This is the first automatic since 1972 (15 trucks later) and the allison is all I could ask for in an auto (except maybe more power handling capabilities stock) but I sure wish I had my 555 Cummins in it or a LB7 without the injector problems. Geo

Hey guys, what about the damned turbo bark??? My truck seems to have ALOT of this on hard accel. That's the only noise that concerns me.

All I can tell you guys is welcome to the world of the EPA. Until these manufacturers figure out how to get big power numbers with very low emissions, this is what we are stuck with. I'm pretty sure a LB7 with the emission controls the LLY has would feel like it fell on its face. I am very happy with my LLY. I would have to bet that the two trucks would be about equal power and rwhp on the dyno.