Considering Buying LBZ Dually with 500k+ Miles

[JAG91761]

I have an opportunity to buy a 2006 LBZ Dually with 500k+ miles. The head gaskets have been redone, and it’s completely stock. The owner is asking $10k and selling because he bought a new Duramax Dually. I plan on upgrading it to manage EGT, coolant, and transmission temps, and it’ll be used just for towing.

I’ve owned an LLY Duramax since 2005, so I know the basics but I’m not a mechanic, just a DIYer. Would you buy it at the right price? What should I look for at 500k+ miles? I’m avoiding DEF and want to stay with zero payments on a newer Dually.

 

[2004LB7]

Really depends on the condition of the rest of the truck. Rust on body panels? Frame? Rotors and calipers? How does the interior look? Some wear and tear is expected for that many miles but is it going to be a maintenance money pit or has it been taken care of?

If it's in good shape I don't sweat the miles. I would probably plan on a transmission rebuild sometime down the road. Or at least a refresh. But if it runs good you might be able to push this off for a long time. Another one might be the CP3. If it's getting weak then a new one can really wake up the engine and restore responsiveness.

Any photos of said truck? Are you able to see it in person and take it for a drive?

 

[JAG91761]

California-owned, so there’s zero rust that I can see, but I’ll need to take a closer look. I’ll take some photos and post them if the owner allows it. The owner says maintenance has been done based on the manufacturer’s recommendations, with oil changes every 5k miles. It’s a GMC Dually, and I’m sure he’ll let me drive it once we arrange a time. The truck is in storage, and I’m working on a time to check it out. My biggest concerns are piston, rod, crankshaft issues at this mileage. Just wondering if this is a waste of time or something worth considering.

 

[2004LB7]

Worth it.

If it's stock and maintenance was done correctly there is little to worry about on the pistons, rods or crank. One can make an argument that if they where going to fail then it would have already. In stock form these engines and transmissions last a long time