I'm currently looking at an 07 GMC with the LBZ engine and Allison. It currently has 204k on it. I know diesels easily last longer than that before needing any major work done on them, but I've been reading that the life expectancy the GM issues to the duramax is only 250k, and that will be 204k miles that I don't know how its been treated. I drive a 96 chevy 6.5 diesel that has 195k and it runs strong still so I'm thinking that a d-max should easily last twice as long as the 6.5, as the 6.5 isn't the toughest engine built. I bought mine with 186k and now every fluid is leaking from the thing. I was wondering how long the LBZ d-max typically last before it starts to have problems such as leaking and power loss. Also, mine has the nv4500 tranny and I know manuals last a hell of a lot longer than automatics, but I've heard some wonderful things about the Allison, and you can't find d-maxes with manuals. How long does the Allison last? And what kind of mileage do these things typically get? It's setup is 07 LBZ, extended cab long bed 2500HD, automatic 4x4. Thanks

I know the LBZ/allison is a really good combination, and many guys have had impeccable luck with them, as for life expectancy, they are one of the most problem free duramax powered trucks you can buy, if well looked after they should run for a very long time, I once saw an 07 lmm(NEW STYLE) with 500k miles on it, the guy used it for hot-shot services so the engine was never cold for long

I can't say that every truck will last that long, but I can always hope as mine only has 130k miles on it and I hope to keep it until the wheels fall off