First a confession...I asked the forum a question about buying a diesel van. Most said to get a gasser instead. Please don't cast me aside because I didn't listen the first time...
I bought a 2006 E350 with a 6.0L diesel. Has some issues I hope to work through, or failing that I'll ditch the thing and learn a lesson.

The pressurized coolant reservoir has a crack/leak in it. Is it wise to only replace it, or should I look for a root cause? The temp gauge does not go past 50% pulling hard up a mountain pass.

This was a fleet vehicle that was pretty much abandoned. There is a chance the reservoir was cannibalized for another rig and had the bad part thrown there but I'll never know.

 

You need:
- new thermostat
- new degas bottle
- new degas bottle pressure cap
- new fuel filters for rail and motor, OEM only and a 36mm socket
- new Oil and oil filter(OEM) 5w40 diesel
- probably new batteries
- scan tool to read codes, clear codes, monitor real time values

 

Looks like a solid list. T-stat doesn't look that bad to get to.

Since the list expanded beyond cooling system, what about the transmission fluid? ~151K miles on it.

 

Add coolant to the list also, but first read up on "silicant drop out' and ELC CAT-1 coolants vs Ford Gold.

 

Also, I'm not familiar with the remote Oil filter on the E - one of the greatest risks is that there are aftermarket Oil filter caps that are taller than the OEM, get a picture of the Oil filter cap on yours with a measuring tape showing the height of the cap.

 

Here is a link:

6.0 Powerstroke Oil Cap Problems and Differences | Ford 6.0 Powerstroke Oil Filters

 

Wow, all sorts of things to learn. When I go looking for the remote oil filter I'll see what it looks like. Might be a completely different style too.
Thanks!

 

Transmission fluid should be serviced every 30k miles.

As Copper.Farm said - monitoring the real time values is crucial. Dash gauges are useless.

Cracking degas bottles aren't uncommon, but overheating can cause premature failure. Monitoring the actual oil and coolant temperatures is one of the first things for people to do BEFORE buying a used 6.0L, so if you didn't do that, don't delay in getting an electronic gauge system.

 

I've got bluetooth OBDII that I can monitor real time with bluetooth. I'll probably look for a more permanent display that is easier to turn on off, but first I need to find out if this old girl will run for me.

 

You might find that once she is up and balanced, that you'll be able to feel when monitoring is actually needed and not depend upon it every day. All up to you.