Looking to buy used D-max

[WSS]

In a month or so I'll be in a situation to uprgade on my pickup. I'm looking to get a '03 or early '04 GMC Duramax. Want to get an older one for the better mileage. I understand the early ones were prone to injector problems. Will a dealership look up the VIN for me and tell if they have been replaced? Also I would like to go with the six speed. This may be another problem with the flywheels. Have they updated this and how can I found out? Also any of you with an earlier D-max and the 6-speed can you tell me your impressions?
Thanks a bunch

[tennessee rockhumper]

not to get to far off track but if you were to look for a 2004.5 instead of a 2004 you would get the generation II duramax LLY, i.e. the new garrett turbo, lower emission, more power, easier to work on injectors blah, blah

[1967K10]

Sent ya a PM'.

[35xj]

Make sure you drive a 6 speed before purchase. I had one for a weekend and ended up giving it back and waiting for a CTD.; That truck had the weirdest clutch i've ever driven!

[WSS]

I've driven a few allisons and 1 6 speed last weekend. The clutch definetely felt different. For those of you with manuals what have you been getting for longevity out of them?

[1967K10]

The stock clutch won't last at all.I have 20k on my stock one and it's gone.The SBC setup I have on order is supposed to last the life of the truck unless you are sled pulling a lot. I'll know a lot more once I get it in and push 550-650rwhp and 1200-1400 rwfp torque to it.I spoke with the owner of SBC last week and he said it would have no problem handling 1000rwhp.

[dogger7]

Check www.dieselplace.com lots of good info for you.

[postal]

Not sure why you prefer a manual, I always did too. The last three trucks I had were Cummins powered with 5 or 6 speeds. With the last purchase I was looking for more room than the small Dodge quad cab. When I drove GM's with the Duramax/Allison, I really liked them. The Allison is pretty sweet, so I bought one. All I'm saying is test drive an Allison-equipped truck if you haven't. It really works well for towing and everything else. Nice used Dmax trucks are hard to find already, and a manual trans in them is relatively rare. I drove 300 miles to get mine. I believe the stock power numbers are lower with a stick also.

As far as injectors go, the dealer can look up the records on the truck to see if they've been replaced. They did for me. If they have not been replaced, GM has extended the warranty on them to 200K miles.

I love mine, and it's getting 17-18 mpg on winter fuel.

[Loco]

I have both a 6speed 03 bought used and an 04.5 allison bought new. I love both trucks. Advantage I will give to the 04 because you don't have to shift and the power is better. But my 03 gives me 20mpg. Had a bought new on the 03, it would have been an automatic, but since I got such a good deal on the stick I bought it and don't regret it.

[1967K10]

Another thing to look at is the 04.5+ have had some overheating problems.I personally wouldn't buy an LLY. I can't notice the power difference between the LB7 and the LLY.Now the new LBZ has a noticable ammount more power off the line.

[88Toy-let]

Another vote for the allison. While I have always been partial to manuals for towing, The d-max seems to hate pushing a manual. by the time the turbo starts to spool up, your letting of the gas to shift. It just feels gutless. The allison has proven itself in service as being fairly reliable. Ive driven more than my fair share, being a gm tech. Also, to comment on the LB7 injector problems, Gm put a recall on these trucks to replace the fuel filter. It was determined that some filters didn't have a rust preventive coating on the metal, and the water traps in the filters were rusting out and sending crap through the fuel system sticking the injectors. So to all d-max owners, change your damn fuel filters regularly, so tchs like me don't have to replace those pain in the ass injectors.

[Toy 4Runner Man]

I would be careful with the '04.5 LLY. There is some weird issues with them, and GM doesn't seem to want to care about it. It isn't every truck, probally just a small percentage of them. My brother had one, and empty he was only getting 13mpg, where my '04 LB7 empty/local gets 17mpg, and on the highway 18-20mpg.

I have a '04 LB7 w/ Allison, and I love it. It is mainly my wife's DD, but over 15,000 of the 33,000 miles are towing. I haven't had any of the injector issues, but I beleive that the problem was fuel related. I mainly buy fuel at two different stations, and haven't seen any uglyness in any of my filter changes. But with that said, I am taking my truck in Friday for the recall on the fuel filter.

[builttaco]

save and get the new LBZ. I did and it is amazing, the power and smoothness of the 6 speed alli is awesome. I also can't believe I am driving a diesel because it is so quiet, but if you want to hear the turbo spool just roll the window down and hear that beautiful whistle. Just my 2 cents

[postal]

The dealer took care of the fuel filter replacement while my truck was in for the loose steering column issue. I asked what the fuel filter campaign was about. They told me GM had run out of filters a while back, so some had not been changed on schedule, and this is how they were making sure they were all changed.:shaking:

[scotte]

They told me GM had run out of filters a while back, so some had not been changed on schedule, and this is how they were making sure they were all changed.:shaking:
That's not quite correct from what I've read at The Diesel Place - I think it actually has more to do with injector issues as it's cheaper and easier to replace a filter than injectors. The filter recall involves a new filter design with much better filtration. As I understand it, injector issues (with all the latest Diesel engine designs) boil down to keeping the fuel clean.

[88Toy-let]

the problems with the injetors is a fuel problem. All of the injectors I have replaced have had what looked like coffee grains at the fuel line connection. Before knowing of the fuel filter issues, we had dropped the fuel tanks, and removed all fuel lines trying to find the source of the contamination, but never found anything. Gm announced our monthly training seminars before the recall and stated that in some cases the filters were rusted through. I don't care how well you design an injector, I wouldn't expect it to last long forcing rust through it at several thousand PSI. Also, many of the trucks that I have seen with issues were abused and neglected farm trucks. And builttaco, you're right, the new LBZ engines are freakin awsome!!!

[1967K10]

With my new SBC clutch I'm running close to 500 HP in my 6spd and it will speak for it's self. I know one guy running over 800 hp with a 6spd.They are not crap like everyone thinks.If stupid GM would use a good flywheel and actually produce a few more maybe people would actuclly buy a few more.It takes $2000 to make a 6spd handle up to 1000 HP but an Ally it takes $3500+.Now I know most people buy them for tow rigs but even with a 120 HP chip an Ally will take a dump if it is used much. By the way 88Toy-let if they can't take abuse then I had better get a CTD because we Farmers and Ranchers do abuse them a good bit.

[sbrem]

If stupid GM would use a good flywheel and actually produce a few more maybe people would actuclly buy a few more.

I agree. Every time my local dealer has a 6 speed on the lot, which is not often at all, it seems to sell very quickly.

[88Toy-let]

The duramax can take the abuse dealt out by farmers. Its the neglect that gets em. Ther injectors are a sophisticated design that requires very clean fuel. The ports at the end of the injector are extremely small, barely even noticable to the naked eye, so the smallest piece of dirt, rust, or whatever can plug it. Why are they so small? better fuel atomization, which means more power, better fuel mileage, and cleaner emissions. The fuel filter needs the water trap drained every oil change, and the filter replaced every 15,000 miles. And regards to the manual 6 speed flywheel, gm has a new dual mass flywheel for the d-max to cure the previous problems, Part #24232434. also gm recomends the bolts be replaced, part #97226124. If your dealer acts like they don't know anything about it, its under service bulliten #04-07-31-006A.

[1967K10]

It sucks when you don't change the fuel filter often.My Dad waited too long to change his and it cost changing it on the road at -10 degrees,which which sucked. Will the new DMF handle 500 RWHP? I'm quite satisfied with my SBC SMF but some people will prefer the OEM peddle feel.
BY the way if anyone wants a 6spd there is a nice 03' Chevy,ex-cab, 4x4,LB,less than 30k,with spay on liner,ect for $27k on the Dieselplace.com right now.Located it MT. Would be a good buy.

[dogger7]

I think all of the new diesels have had problems with injectors. GM, Ford, Dodge.