Looking for a duramax probably

[viper6383]

Well, in other posts, I was looking for mod my 95 Z71 for more go but coming around that the Dmax is what I need. I will probably start with the basics of tuner, 5in straight exhaust (unless that will create problems without a muffler), and intake upgrades. Later I will pull that turbo and look into porting it and inter-cooling. The cost of the truck alone is staggering.

I would have to buy used and wondering what years to look for or stay away from?? I was feeling the 05-07 range. Should I wait to buy? Is anyone seeing failures by pushing so hard on these motors?

I will likely own this one for 10 years too so it will need to last.

[nova801428]

1

[Sleeper_6]

your advice made very little sense..

[scottsdale1955]

I just got mine a little over a month ago so I can't really comment on reliability, etc, and this is my first diesel as well. But from what I learned from other people was the LB7 motors (01-04.5) had injector issues. Causes vary by opinion, I guess. the LLY's (04.5-06, I believe?) had heat issues where some people would end up w/ cracked blocks, I think that was less common then the injectors thing. And the LBZ's (2006+) had a lot of restrictions emmission wise. I may have the LBZ's confused w/ the new one, the LMM, but I'm sure someone will correct me if I'm wrong :) Sorry this isn't really vast information heh. If you want to find out more, go to dieselplace.com IT's dedicated to GM diesels. Other than that, you can decide if you want the allison auto or the 6 spd. manual tranny. That's toatlly an opinon based thing, so I think.

Talk to Foreman, he ought to have some decent input.

Good luck!

[viper6383]

Yeah, the Allison is a must. I hope they are holding up. So I am hoping the latest motors can be "unplugged" if I go that route.

[Farmer98]

Scottsdale, I don't think that the LBZ has emission restrictions as does the new LMM.

[justy]

Haven't had any trouble with the duramax. Only thing that did fail on me so far was at a truck pull. I broke the factory receiver hitch. When it broke free I had to stop and get out to see what happened. And behold there layed part of my receiver on the ground still connected to the sled chain. Now I got a home made receiver on there. But thats one thing I learnt from trial and error sled pulling. The other thing I had to replace was the rear bumper. Got a good used one from a junk yard for $200 which wasn't bad at all.

[viper6383]

So what mods do you have on that max to rip the hitch out? I have heard many horror stories about the trannies causing a limp mode due to trans slip if you push much over 700 torque. I am looking for more than that so what is needed to do it? I have heard there are some simple trans kits that install without a complete rebuild but I have not read too much into that.

[foreman00081]

for big power you have to build the tranny, shift kits alone are not enough, new clutches and a new torque converter are a must. the allison is hands down the best tranny going now but they are not made to hold more than maybe 100 extra horses over stock or they will most likely limp and once they limp it will do it easier each time after. i had my tranny built by Eric Merchant, one of the top allison builders in the country so now i can probably go to about 800 HP if i wanted to. now im not planning on going that far, im at 372HP at the wheels now, 679TQ and im looking to get to about 500RWHP. after 500 or so HP then you need to start looking at engine internals and im not going that far cause then your talking serious coin and i dont have the time or money to get that far into it. heck the tranny alone cost me almost $4k. so if youre planning on that much power you better have some deep pockets, not trying to discourage you, just letting ya know, it gets expensive quick and its more addicting than crack laced with crystal meth. but like scottsdale said, for more info than youll ever want to read about dmax's and modding them go to www.dieselplace.com , thats where all of the leading authorities on duramax's hang out.

as far as what year its pretty much your call, the 01-03's (LB7) did have injector issues but they are warrentied up to 200k miles by GM, mine are still original at 108k and no problems yet. some of the LLY's (04-05) did have some overheating issues but im pretty sure thats all been fixed by now. the LBZ's (05-07) i dont know a ton about but im pretty sure they were the first years with the variable turbo which gave it more power. the newest generation is the LMM which i believe is just about the same as the LBZ but with a little more power and the new emmissions standards including the DPF in the exhaust. and as far as reliability goes they are holding up very well, theres plenty of dmax's with 300K+ out there, ive personally seen a couple and even seen one with over 500K and have read about one with over 700K on the clock. now as with anything if youre making huge power and beating on it hard then it wont last as long but thats to be expected.

[viper6383]

Yeah, you kinda hit on a key point and that is reliability vs HP. My goals are around 500HP but I guess as long as I am not hammering on it everyday, I would think it would last to 200K pretty easy. The way fuel prices are, I try N O T to drive much. I will have to hit these other forums too and see what the Dmax is all about.

['96 Z-71]

Check out dieselplace.com. You'll find out everything you want to know there.

[foreman00081]

500HP isnt huge power for the dmax so really all it takes is a built tranny, exhaust, gauges, tuning, usually EFI live or PPE to get to 500HP and reliability should still be good, at least thats what im hoping cause im shooting for around 500HP by next year or so. honestly the 372RWHP i have now is more than enough but 500's just gotta be sick. once you go over 500 thats when you start walking that thin line of reliability and need to look into larger turbos, engine internals, stuff like that and thats where i get off the bus cause i dont have the time, money or knowhow to get that far into it.

[Lifsvr7]

sweet infor thanks