140,xxx here. On my third 7.3 OBS truck.
I tow sometimes and you want to monitor EGT (exhaust temp) so you don’t burn
everything up. So get an analog or digital reader for that.
I like the electronic dash reader (specifically Edge Insight CTS3) because it will give you codes, oil temp, trans temp, EGT temp (with additional adapter), etc etc etc.
I have tuner as well to provide better daily driving, towing, quieter at the drive thru mode, etc.
Glovebox items: fuses, sockets, wrenches, CPS, IPR, etc
Good site I like for parts/ advice (and owner knows his stuff / but hard to get ahold of unless you email) is Riff Raff Diesel (Ford diesel trucks).
Because you have two of the same 7.3s - you can prob have a “kit bag” that ya swap out depending on which 7.3 you are driving. And if you intend to keep both - I recommend once you encounter a problem on one - then put a new part on the other vic because the hardest part is doing the fix once (but to do it on the other vehicle will be so easy).
Fuel treat when cold but pay attention to local shops that sell diesel - some will pretreat their diesel with anti gel down to a certain temp (check with locations that sell it and see what they say). That can save you money because you won’t always have to add in the anti gel yourself.
Lastly - depending on where you live - ask around for a good 7.3 diesel mechanic that has experience. Most of the time you can solve yourself, but sometimes those local diesel mechanics can just tell you the prob by listening to it idle or “attempt” to start up. I was up in Wyoming hunting and popped over to Idaho because there was a retired Ford mechanic (7.3 diesels) that had a shop. He helped me ID a quick/cheap fix which was the glow plug relay, but I had already spent hours trouble shooting other issues which were closely related. So word of advice, if sometimes giving you a hard start in winter, check the glow plug relay ha.
Good luck. Take care of the 7.3s and they will take care of you !!!
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