after my oil changed I notice my oil pressure Max is out until it heats up then stays around 20 until I accelerate then backs out a

Just started for the first time of the day
bove 80

 

What kind of oil? temp outside at time of start? Odd even new thicker oil shouldn't be that high, did you check the level? Has it been running my differently?

 

I assume 5 w 30 I was getting a new transmission put in got oil change while I was at it

 

Live in Minnesota is around 60 degrees when I started it first thing in the morning

 

I checked the level of oil when it was hot seeing fine yesterday I check cold today looks over full

 

I assume 5w 30 I just got my transmission replaced so I threw an oil change it runs the same when it warms up it idles at about 40 soon as I accelerate maxes out

 

I seen one of you comments saying might be over full, maybe get a clean container, drain some out, then check again.

 

Off topic, I seen you got a wood grain speedo? What trim do you have? Or is it aftermarket?

 

You may have a sending unit taking a dump or a partially pinched wire for the sending unit between the block and bell housing from the transmission change out .....

 

Yep, I'm voting for something with the oil pressure sending unit from the transmission repair. It's right there behind and to the side of the distributor near where the trans bellhousing attaches to the block. No way that is a real oil pressure. You can always check the resistance of the sending unit against specs.