I just got my first Diesel truck. Its an ?84 Ford F250. The engine only has 70,000 miles on it. I am used to doing the regular maintenance on my old F150, (oil change, tune up, air filter) is there any different kind of routine maintenance that I need to know about for a diesel? I already found out that I don?t need to do a tune up on it 
There are no spark-plugs…so you can eliminate that.
Outside of that…everything else should be close to the same. Oil changes…filters. Just be sure to use an oil that’s rated for Diesel…NOT ALL OILS ARE.
Also adhere to the oil and filter change schedule in the owner/operator manual and change the fuel filters with quality units on the manual’s recommendation. Find out if this truck has a water separator; if it has a warning device; and how to drain excess water. The air filter will have to be serviced more often because of the amount of air going through the engine. A blocked air intake on a Diesel of this year would probably show up as black smoky exhaust on acceleration. Some Diesel air filters have a air depression telltale that shows up when the air filtration system is excessively blocked.