@Aleckb Would you please let us know if you have ANY issues with the change to 20w-50, A concern will be with the MDS system throwing a code, not working as expected, also the VVT system codes etc. You may have no issues, but if you do please let us know.
Glad you have your issue with the pressure fixed.
Excuse the temporary dyslexia, I did use 5w-20 in it, not 20-50w and as a mentioned oil pressure is great.
However, now having other problems.
Ugh...where to begin. I'll re-post this back to the main forum too but in a nutshell...
Before I noticed the oil pressure problem there was some ticking on the drivers side, thought it was lifter so I used a stethoscope but didn't hear anything so I assumed it was an exhaust manifold bolt and but then got wrapped up in the oil pressure problem.
Then, during all the work on the oil pressure problems I noticed the ticking stopped...which is obviously not a bolt, since they don't fix themselves, so I assumed I have valve train problems, which undoubtedly will come back.
So, in summary, now, oil pressure fixed...no codes but now getting a 219a code which is an air/fuel inbalance in bank 1. Idle is perfect but truck misfires starting around when shifting into 2-3 gear and at highways speeds. Gas mileage went to crap, barely 12 (was 16-18) now and really bad performance.
Truck was due for a spark plug change at 90K so I did that, put OEMs back in and also changed PCV valve. Plugs didn't look that bad when I pulled them so I didn't think that was the problem but changed them anyways to be sure.
Cleared code but it came back, same thing 219a.
I would be expecting the worse because I did hear the ticking before (It hasn't come back and still sounds quiet with the stethoscope) but was has me stumped is when I put it in tow/haul I can get the problem to stop. If I am just cruising with no load the the misfiring stops and 16-18 mpg again on the highway, however, accelerate, go up an incline and the misfire starts again. Once the load stops the misfire goes away and the mileage goes back up again.
I know there are other things a 219a could be, fuel injector, ignition coils, O2 sensor, valve train...but the tow/haul thing has me thinking it's not the valve train and it's something to do with the MDS?
Which, btw, I do not have the 'ECO' light, not there and can't enable it. Doesn't work and do not have the option to enable it so I don't know if the MDS is coming on or not.
Anyone have any ideas?