Oil pressure gauge bouncing

[Dan1]

I just purchased this truck seeing that the oil pressure gauge was pegged at 80 when I looked at it. While driving home I was scared when I saw "low oil pressure" waring lights flashing. Then I noticed the gauge bouncing all over the place from hight to low. 

 

My last trucks have always just pegged to 80 when the sending unit when bad. I know the true way to get a reading is to put on a mechanical reader. In the meantime, please tell me this is just the sending unit... please...? 

 

Seriously, engine sounds and runs like it is new can't imagine it is going from 0-10-5-80 psi that fast unless there is a history of oil pumps going in the 4.8. 

 

 

[CamGTP]

Replace the sending unit, it's likely that.

[Dan1]

yup - that was it. I was very happy to see the pressure between 40 and 60. Went straight to 40 right after start up so its a healthy engine!

 

Never saw it swing like that before. I always just saw them pegged at 80 or at 0