[455Grandville]

Originally Posted by Sirrotica

There are lots of people that have no clue what it takes to keep 6.5 diesels together. Not to say that GM didn't have bad castings in the earlier ones, cracked blocks right up through the bulkheads just like Pontiac does when you overstress the blocks. The harmonic balancers have a habit of coming apart, and if you don't catch them they break the crankshafts soon after the balancer goes south.

They also had a propensity to crack cylinder heads from overheating, and blow headgaskets. ARP studs and good headgaskets usually solve that problem, but mine still have the factory bolts in the heads, one in the 95 is bubbling in the radiator so it probably has either a cracked head or a headgasket starting to go, I just acquired that one within the last 30 days, we'll see what happens with it.

The 93 runs just fine, has only had a waterpump changed out since I bought it in 2011, and I had to change out the injection pump when it took a dump.

They can be bought pretty cheap, and because they are mostly not heavy on electronics, you can fix them cheaply. Same engine that the military Hummers used until AM General quit making them.........

I guess I lucked out with my two so far...........LOL

Plus they used cast cranks (in a diesel !) which was a weak spot as well. They also tended to run hot but GM fixed that around 1995 with dual thermostats. There was a control module under the intake that liked to go bad and the solution was to relocate it. Imo if you leave them stock except for updates and don’t overwork them they’ll do ok.

I just preferred the International 6.9 and 7.3s that Ford used a lot more as they were pretty tough engines. You just can’t expect them of the 6.5s to compete with these new diesels but they are much more simple and cheaper to repair.