2010 international 4300 maxx force reading no oil pressure on gage but runs fine

My 2010 international 4300 tow truck flatbed oil pressure gage dropped to 0. Pulled over checked oil all seemed ok engine n everything.Was over 200 miles from home drove truck no overheating nothing strange except oil pressure gage and warn engine* on panel. I've done a complete tune up oil change n everything which it was almost due 4 another. N still same thing the oil pressure gage still on 0! I purchased another but don't exactly know where to locate it. I'm not a diesel mechanic I ideally do regular cars or trucks... help anyone?

 

Yes my thoughts also. I bought it but don't know exactly where is located...

 

Thank u so so much!!! Greatly appreciate it! That I much figured because I made it all the way back home no problems except the gage n warn engine message on panel. N the bad thing is that I have allot if work but but didn't feel comfortable driving my truck like that. Need it 2b 100%.