Series 60 Detroit

The ECM is on the drivers side, halfway back, down low on the engine. On top of it will be the series it is. It will read DDEC and then I-II-III, or whatever series it is. It is black with a lot of wires connected to it.

 

i don't know what the value of the truck you want to buy is but you may want to consider having the owner take it to a NTP type place that offers warranty on used trucks.For around $500 they will dyno and check different engine components, trans. and rear axles.This is usually done on newer trucks that you might be wanting to buy and want some type of warranty,but in your situation it may help you have a better idea of what you are buying.

 

Some had issues with the camshaft lobes wearing fast.
Air clutch fan bearing, if it galls up, it will take out the radiator.
Check for cracks in the fan blades itself.
Check and see if it had its 100K PM service done.
If possible, hook to a load for a road test with it and get it to operating temp.

 

I'm going to say that I doubt a 20 year old truck has 200k miles on it. My 93 was a DDEC 3 and I still see it occasionally around town. It had 1.3 million on it when I sold it in 2005, and the lower mileage was due to running regional for most of its life.

The Series 60 is easy to work on and was originally designed by John Deere. It is the only engine I've ever owned: 11.1 DDEC 2, 12.7 DDEC 3, and three 12.7 DDEC 4 engines. It's a great engine, but in a 20 year old truck, engine reputation means diddly. Oil analysis, having the ECM downloaded to see just how many miles are on it, and maintenance records are what counts. Overall condition of the truck matters as well, because the parts may be outdated and have to be ordered instead of being in stock.

 

On a twenty year old truck what are the chances that the ecm is even correct? As far as miles are concerned.