I took a test drive in a Crew Cab short bed 4x4 LBZ yesterday and was surprised that it didn't have the grunt and power that another one that I had driven a few months ago had. I thought that this was the truck I wanted, granite blue, with the LT3 package, with grey leather, but after that test drive I was really disappointed. There was even a lull when I hit the gas at 60 mph, and when it did pick up it didn't have the hard pull that the other truck had. I had to say no to the deal - actually I was so disappointed I didn't want to talk figures with the salesman.

It makes me think that I need to find mulitiple units of the truck I want then drive each one to see which one is best performer of the bunch. So it would be hit or miss if I ordered one.

sounds like a ford 6.0 from one motor to another it could be night and day

Are you Sure it Was an LBZ:cool: ???

Are you Sure it Was an LBZ:cool: ???

It was definitely a 360 hp / 650 ft lbs torque engine on the window sticker.:wtf:

Running in tow/haul ?

did you ck if anybody dissconected any of the spark plug wires on it?

:funnypost

When I test drove mine it had 6 miles on it and it seemed kinda heavy and slow compared to the Z-71 I had. After I put about 600 miles on it it really started to wake up. I'm happy I got mine. If I don't do anything to it performance wise it is faster than my last truck. Go ahead and get one I don't think you will be sorry.

If it had no miles on it, it probably did feel like a slug. Also, were the gear ratios in the diff the same? That would also make a noticeable difference.

If it had no miles on it, it probably did feel like a slug. Also, were the gear ratios in the diff the same? That would also make a noticeable difference.ALL 2006 2500HD and 3500 GM trucks with the Duramax Diesel engine come with the same axle ratio (3.73:1)

Don't the rings have to seat at least 1,000 miles before you can start comparing motors. You don't know how this truck will be when it is fully broken in.

You don't know how this truck will be when it is fully broken in.

I just couldn't believe what a difference between the two trucks there were and the one I drove the other day had 150 miles on it, the other (fast) one had only 12 miles on it.

What color was the one with 12 miles on it? And where is it? I am looking to buy right now.

I test drove (2) LBZ's and found no difference in their perfomance; also drove my friends' LBZ after it was lifted (no chip or anything) and there was no big difference in performance either (felt exactly like mine when I took the BD out to have GPCM flash.) Of course, his is the same color as mine...and I have heard that the Graystone's run a little better than the other colors......:blahblah:

Not to start crazy ideas on these trucks but I really do believe something is going on here. Some trucks fuel economy suck and some are great. My truck has alot more power than a friend who has a LBZ. I wouldn't believe any of it until they all go on a dyno.

STOP IT!!! I won't believe that the duramax quality is as bad as the PowerChokes!!!!! Don't do it!! NOOOOOOOOOO!!!!!!!!!!!!!!!

I just couldn't believe what a difference between the two trucks there were and the one I drove the other day had 150 miles on it, the other (fast) one had only 12 miles on it.

perhaps you just became accustomed to the power, thats why the second drive in another truck didn't "feel" as fast

Just put 6000 miles on the clock, and the dmax is starting to come alive. I believe these motors do not break in till they get some miles on them.:Nothing_f

takes 10-15000 to break them in. i know mine started coming alive around 5-6000. gets better everyday i know have 13000 on it. happy shopping

I agree B4 I bought my chev LBZ I drove two diff GMC lbz's, they bother ran like carzy and sounded good as well. I ordred my chev lbz and was surprised at how gutless it was and how many rattles and misc odd noises it made ( engine wise) That being said, after about 4K miles things seemed to have changed, good mpgs's and good power but its been a while and Im probably just used to it. But man, those GMC;s I drove just cranked....

I see another GMC vs Chevy argument coming on..............let's all just play it cool this time. GMC or Chevy, they are all the same. Except for my truck, which is better than yours!!!! :joke: :joke: :joke: :joke: :joke:

As much as I don't want to belive it. I think I do. I drove 2 before buying, have driven 2 friends' trucks, none of which were white and all of which feel like they would smoke my truck.

Summit white ones must be slower.:rolleyes:Censored

Only 2k miles, so we'll see.

Ian

Been in the industry for thirty years and you are right .

I found the same thing when looking at new D/A's a while ago.
Drove a GMC CC/SB 4x4 and it RIPPED! Freeway on ramp, it smoked the rear tires on the 1-2 shift.
Drove a Chevy, same style truck, cc/SB/4x4 and it felt pretty quick, but not as fast as the GMC.
I know they are the same truck w/ different badges, but the 1st one felt alot quicker. Neither truck had many miles on it either, under 100 mi on both of them.

As much as I don't want to belive it. I think I do. I drove 2 before buying, have driven 2 friends' trucks, none of which were white and all of which feel like they would smoke my truck.

Summit white ones must be slower.:rolleyes:Censored

Only 2k miles, so we'll see.

IanI beg to differ.

Beg.

I wonder what it is that really makes the difference. Ring seat? Shouldn't matter when low mileage. Variances in turbo performance? Is it some little do-dad somewhere, or just variances in tolerances that either work in harmony on some and chaos on others.

And, which one is really the anomaly? The fast one that will tear the tires up on the 1-2 on dry pavement and gets 16/20 or the ones that won't break them loose when wet and get 13/17?

Love my truck. Wish I had a strong one

May sound funny, I've driven a lot of the LBZ trucks, but the 06 LLY I bought a few months ago will smoke most of them.

You will find this same senario with any car out there, some will be ringers, and some will be duds. I have a Mitsubishi Lancer Evolution and know a bunch of others who have them as well. I have driven one that was totally stock and it was just slow. The numbers on an all wheel drive showed it to be down about 15-17 whp. Another buddy of mine had one that on the same day, totally stock made about 12 whp more then what other stockers were making and both cars were between 3000-4000 miles. Even when he started to mod it, it was making more then similar cars with similar mods. Some cars are just more equal then others.

Would it be crazy to set up an arangement with a dyno shop and have the speculative units dyno'ed? I am trading a warm running 04.5 for an LBZ and they have 6 to test.

I took a test drive in a Crew Cab short bed 4x4 LBZ yesterday and was surprised that it didn't have the grunt and power that another one that I had driven a few months ago had.

It makes me think that I need to find mulitiple units of the truck I want then drive each one to see which one is best performer of the bunch. So it would be hit or miss if I ordered one.

You are right! They are not all the same! I owned an '02 that never ran strong! If it doesn't run strong, don't buy it! If it's a dog, it will still be within GM specs and you are stuck with a dog! I've been there!

I have to sell my brand new LBZ because of health reasons. I live an hour from you! Take a look at my ad for a '06 Crew Cab short bed 4x4 LBZ with only 2970 miles in classified section! It ran strong from the very beginning and it gets 20 to 23 MPG. I love it!

Yes! Scientific testing has shown that white ones do run better! :D

I Think On The Assembly Line, Someone Got A 6.6 Mixed Up With A 2.3 4 Cylinder . That Duramax Was Running On A Cavalier Or Impala Engine. Thats What Happened. Duh!!!

I bought a Deep Blue Crew Cab (just got it home) I left the dealer with 10 miles on it. I stomped on it as I left the dealer to see what it really had. As I turned on to the street if smoked the tires and kept turning them well into second. I think this is the best truck I have ever driven. I test drove six and one was like this one two others were close one never really got it going and the other I didn't have the balls to really mash it. It could be that I didn't have the same attitude when mashing the peddle or the street was rougher? Exhaust, Tuner, EGR block-off, Lift and tires and I think this will be a long time keeper
:exactly:

I think that this may be a subjective problem. The only way to know for sure it to have it tested on a Dyno.

i agree the only way to truly know is to dyno them, but I have driven many of the duramax diesels and within each class (LB7,LLY,LBZ) they all feel pretty close. Then again that is just my opion.

Just take it to the dyno on the test drive :D

I have a hard time believing a stock diesel of any kind will "smoke" the tires. My truck won't do it, my step mom's LBZ won't, even her 03 she just got rid of with a 110 hp quadzilla wouldn't spin the tires if you just flat foot it from a dead stop. Maybe the pavement the trucks drive on that "smoke" the tires is just really crappy.

Trying to find the strong one!!

I have a 'overheater' LLY CC SB and have been evaluating switching to a LBZ. My dealer was kind enough to set me up with 6 identical trucks to try and avoid a dog this time around.

My test started with my truck on a 10 mile loop which included same speed highway cruising and a timed acceleration test between a couple of highway markers (no powerbraking and starting on concrete)

My truck managed 85 mph and and a time of 24.9 seconds - no tire spin with Michelin tires-it has never spun the tires:(

All trucks were pretty even and each one of them would have tire spin that started about a truck lenght from the start and extended into second gear. This did hurt the elapsed time and would hit the 95 mph speed limiter 3-4 truck lengths before the sign. Elapsed time was typically over a second quicker than mine.

MPG figures were all over the place ranging from 12.7 to 14.3 during the test (I know not very scientific but it's all i had)

The truck with the best mileage was also slightly quicker (by my handy stop watch) and the only downer is that this truck has a slight vibration in the accelerator pedal at idle. I had them hold it anyway because of the makeshift performace test.

It was kind of funny to see the acceleration tracks on the side of the highway from testing all of the trucks. lol

Sad part of it is that i am still upset with GM and my OH problems that it is all i can do not to get a Mega Cab with the Limo type room!!