2008 suburban z71
Thread Starter
CF Beginner
Joined: Feb 2019
Posts: 1
Likes: 0
2008 suburban z71
hello ,I am working on a 2008 suburban 5.3(vin 3 with AFM) oil pressure problem. I used a mechanical gage to check oil pressure so I know exactly what is happening. I have replaced oil pump, oil pickup tube o ring, oil pressure sensor, oil pressure relief valve, lifter oil screen. I have good oil pressure (55psi) until I stop at a light it then drops to near zero. But it doesn't happen until after engine is at operating temp and not all the time. Stop engine and restart and pressure is back to normal for a short time. Sometimes at idle the oil pressure fluctuates from 5 to 30 psi. Could I have a problem with the lifter oil manifold or could it be something with the afm lifters?
