Welcome to the tribe.
Don't let the Diesel part scare you.
IMHO, it is as good as a 350 that you would in any other truck, if not better. I like (love) 350 chevy's, but how many can still turn around after over 200K miles without a rebuild.
Like the others have said, it is a 30+ year old truck, no matter how meticulous it was maintained, it will need something. There is plenty of info located here on the site, always recommend to download the TM's
HERE.
Probably the most common things are (they sound like a lot but in reality are not)
These are not in order of importance, but just some off the top of my head.
1 - Doghead mod for starter relay failure (under dash). Relay is not strong enough and tends to stick causing starter to run on
2 - Headlight fuse relay mod (circuit is already overloaded and is the easiest to add more things to it)
3 - Vacuum line for tranny (causes tranny not to shift correctly or not at all, possible modulator)
4 - The famous Death Wobble - this could be a lot of different things from shocks, kingpins, suspensions issues and so on, but comes up regularly.
5 - Charging/Battery issues - Issues arise from bad batteries to 1 or both alternators not charging correctly
6 - Leaky fuel filters - if you have the stock style Stanadyne filter base, they tend to leak. Spin on filter replacements are a common solution, but there are stock replacements and fixes out there.
7 - Speedometer issues - these are typically old gages that are failing, but sometime other issues come up
8 - 12 volt conversions - Usually when someone did not understand the 24/12 volt hybrid system, they converted ot to a regular 12 volt system, or many of the other stock systems failed and they were removed. Electrical demons can come from conversions
9 - Glow plugs/Glow plug cards/glow plug relay/glow plug resistors - these are all prone to some failure at one point, at least every other week it seems that someone is posting something about one or all of these.
10 - IP pumps - as these trucks get older the IP pumps are nearing their life expectancy and can cause some hard to diagnose problems from time to time. You can get these rebuilt, they're not cheap, but they run very well after dialed in. Life expectancy as per TM is about 100,000 miles.
There is always more, but these seem to be the most common ones I see. Others I'm sure will chime in as well
Despite all these that I listed and others will list, I still love my 1009 and would buy another if I had room.
. Good Luck
