hello, I've recently purchased a used LMM Duramax to put in my 2008 Silverado 2500, i have the used motor sitting waiting to go into my truck but I am wondering if there are any modifications i should attempt to make to it while its out of truck, modifications geared towards reliability and longevity. also its used, purchased on marketplace, never saw it run but was told it did, so what can i do to be sure it will work before going through the pain of putting it in.

not a mechanic but can, have, and want to figure things out and do things right. thank you

What else do you know about it?

Here'* a good starting point:

1. Does it run? Seller says yes and has only a few reasons to say it when it is not accurate.
2. What is the make and model of pickup it came out of?
3. What is the VIN of the vehicle that it came out of?
4. How many miles on it?
5. Does it turn over?
6. What is the oil like that'* in the pan? Does it smell like gear oil?
7. What was the reason for pulling it out of the pickup it was in since it ran so well?