I have a problem with the oil pressure gauge in my Grand Cherokee. I had to replace the sending unit (4.0 liter engine). The new one worked fine for a day or two then the reading dropped from 40-50 to 10-20. Took that one back and got another. Same thing happened again. Do I have to get the Mopar part or am I missing something else? Any suggestions would be appreciated.

 

I've heard only go for mopar oem ones for oil pressure sending units. Only like $30 from a dealer (atleast where i'm from)

 

YES....GO MOPAR!! There was a change later in WJ production where the oil pressure sending unit was just a switch, not an actually pressure reader. I bought a NAPA Premium one and all it EVER did was read 30 psi!

 

I tried to replace my switch today but couldnt get the connector off...04 4.7...gonna try again tomorrow after i go buy a 27mm deep socket ( didn't have that anyway )

 

You may need to get a oil pressure sender socket for it. Ive gotten by with channel locks before though.

 

I actually bought a 1 1/16 deep socket for $10 bucks after the guy at the auto parts store tried to sell me a "special" oil pressure socket...it worked just fine...changed it in 5 minutes and gauge works like it should