2000 6.5 litre diesel - good buy?

The 6.2, 6.5 and 6.6 were all designed to be diesels. Only the 350 diesel was a converted (redesigned) engine and actually it was not that bad of an engine it only had head gasket issues. The 6.5 was built by GM but was later "sold" to American Motors General (AMC was bought by GM away from Chrysler and became AM General) who is a sub division of GM (Chrysler only wanted the Jeep brand). So now the 6.5 is primarily used in the Military Hummers with GM replacing it with the 6.6 turbo (duramax) in its heavy duty emission trucks. Imho it is a nice all iron engine I haven't heard anything bad about it. Apparently it is a slightly larger bore 6.2 dsl. If it is not too much I would go for it. Ford would be the 7.3 power stroke (PSD) which is a nice set up but the 6.5 would be less power and probably a lot less trouble. The Dodge is a nice diesel and probably always a nice choice if you don't have issues with buying a truck built in Mexico. Personally I have always tried to stay with US assembled vehicles (my '91 suburban was assembled in Flint, Mich and the '02 Excursion was assembled in Kentucky). I have not owned a dodge but do own a PSD in a Excursion and we have already had turbo and transmission issues with only 22k on the odometer. So all three have their problems but I would probably go with the Chevy if there was a choice. See what others have to say....

good luck, mark

The GM 6.5L diesel ran from 1993 to present in various vehicles, now only available in the H1 Hummer and for marine applications. It is turbo-charged but does not have an intercooler (resulting in the need for lower turbo boost pressures) and has indirect injection (making it less noisy than comparable motors of it's day). While it is not the most powerful diesel, it does generate somewhere around 220HP and 440 ft-lbs of torque. It is the only 8-cylinder diesel light enough to have been offered in a half-ton truck. The Ford/International 7.3L Powerstroke and the Dodge/Cummins were offered only in trucks of 3/4-ton or more capacity due to their excessive weight.

The model year 2000 motor benefits from all the advancements learned from the previous 7-8 years of 6.5L diesels, including a higher flow water pump with dual thermostats. One problem which has plauged this motor since day-one has been the fuel solenoid driver (the black box that drives the fuel injection pump). It suffers from excessive heat retention and has a lifespan of about 75,000 miles on average. Unfortunately it can also cause problems with the optical sensor inside the pump which can lead to a total fuel injection pump replacement and a bill of around $1500.00 or more if it's not under waranty. However, this probem does have a remedy. I owned a

1995 Chevy C1500 with the 6.5L diesel and can advise that one modification I would definitely make to any model 6.5 would be an FSD Cooler (look it up at for more info.). The FSD Cooler places the FSD away from the fuel injection pump and allows it to bleed heat directly to the atmosphere (instead of the pump itself being used as a heat sink). Reply back if you want more information.

The last piece of the puzzle is the transmission. I have many, many years of experience with Ford's at work (fire department), and with friends who have Dodges and can say with confidence that for the model year you are looking at, the GM transmission (4L80E) was by far the best of the automatic tranny's offered by the three major manufacturers. My experience with Fords at work is the primary reason why I have driven Chevy's since 1988.

A good reasource for info about this motor is

Cheers - Jonathan

"rock_doctor" wrote

Interesting....I worked non-stop for about 5 years on the Olds 350 diesels when they came out. It was a "terrible" engine, and it had a lot more problems then head gasket issues. In fact, head gasket issues were the least of it's problems. Premature wear on just about every internal part was common, broken crankshafts, worn rocker arms were really common, oil leaks everywhere. We finally just started getting used gas Olds engines from the wrecking yards and retrofitting the diesel trucks with the gas engines. It was cheaper and a far better engine. Of course, these trucks were no longer on warranty.

Ian

My uncle had a olds wagon and a caddy with the 350 diesels. Luckily GM after a while just gave up and was giving away new engines to anybody that asked. At one point he had one extra for each car.... They generally lasted 40k to 50k miles at which time he would pull the old one and put in a reserve engine. Under most cases he needed to only replace the head gaskets to repair the pulled engine. Maybe he got lucky or since he only put 50k on the engine before he pulled them he was able to repair the head gaskets before any internal damage happened. The 350 diesel was a interesting experiment by GM....

mark

my uncle had an '82 Caprice with the diesel in it... after it cracked the head (90 or '91), he took the heads, intake, and carb off of a '76 Delta 88 and swapped them onto the diesel block, keeping the roller cam and the diesel pistons. if you'd fill it up with premium and put about 10 bottles of octane boost in it, it was like the hand of God pushing you into the seat. I *think* the CR worked out to be 12 or 13 to one. it's still running in this config, it now belongs to a neightbor of my uncle.

-Bret