Hi, I am interested in purchasing my first diesel truck I am looking at the 2005 GMC Sierra 2500hd SLT 4x4. It has 195,000 km or around 121,000 miles on it and are asking 18k. Was just looking for opinions on the milage as well of what to look at/ask when I go to view the truck. Mostly just concerned will longevity as it will be towing trailer/skid steer combo regularly. Thank you for taking the time to help !

 

LLY engines can have a tendency to overheat when towing heavy. There are some upgrades to help with this. As far as looking over truck, check for coolant leaks, have injector balance rates checked. Check for blown headgaskets. Check for trans fluid leaks around cooler lines and t-case.

 

Thank you for the reply. How would you check for a blown headgasket? I am taking it into the GM dealership to get the injector balance rates checked. Just want to make sure they check everything... being diesel dumb doesn't help to know what to have them check. Thats where your list comes in handy! thank you.

 

Low coolant level with no visible leaks, cooling system pressure very high, air bubbles in tank. Hydro lock after sitting for a while.

 

I have yet to see a lly overheat down here In Texas, yet people still say they do. Mine has never overheated.