Cole Shannon

Really hoping someone on here can help. I'm at my wits end with this truck at this point and considering trading it in soon before another catasprohic failure occurs. Within a span of 6 months I had the AFM lifter failure and my trans go out resulting in approx. $12k of repairs. (The shop did not do the AFM/DoD delete). Here's the current issue: my 2018 truck has 141,000 miles. I've noticed recently that once the truck gets up to temp, the oil pressure on the dash goes to almost zero when I'm idling at a stop light. When accelerating or driving, it hovers anywhere between 20-40psi depending on my rpm. I changed the oil and replaced the sending unit and filter screen, still notice the same behaviour. There is also a code P06DD that seems to come and go on its own, about once every couple weeks. I always use dexos 0w-20 oil, with the AC Delco filter, and make sure she's topped off at all times. I did take it to my shop and they were able to verify that the oil pump solenoid was working by commanding it ON/OFF with a scan tool. I've seen some folks say this pressure reading is normal and within GM spec for this motor, but I still have a sinking feeling in my gut about it. Has anyone else dealt with something similar? Is there anyhting else I need to check? Am I screwed and my oil pump is on its way out? Like I said, I'm kind of at a loss here so anything helps.

Right now my 2018 truck with 140,000 miles is hot idling at 10psi on the dash. When driving or accelerating I'm at 40psi. I too have been very religous about doing oil changes evey 5k miles and use the dexos 0w-20 oil. I have replaced the oil pressure sending unit and filter screen and still get that same reading. Never have gotten a check engine light, and never hear any unusal noise form the motor, but I still just don't have a good feeling about it. I'm in the same boat looking for opinions about this, is it a real problem? If so, oil pump? Or maybe a problem with the pickup tube?

I also read recently that the oil pickup tube has an O-ring that can get dry and brittle over time and fail. Is that a known problem on these trucks?

Hey man did you ever figure this out? My truck is doing the same thing… low oil pressure at idle after engine reaches temp, 10 psi on the gauge. I replaced the oil pressure sensor and filter screen too…

Found this read as I have the same question as the original poster… hopefully y’all can help. I have a 2018 5.3 with 140,000 miles. I recently noticed that at idle after the engine gets up to temp my oil pressure gage on the dash reads 10 psi. When driving or accelerating I’m hovering around 40 psi. Around the same time I had the dreaded P06DD code show up, but I replaced the oil pressure sensor and the filter screen behind it, changed the oil and oil filter, cleared the code and so far it has not come back. But the oil pressure reading still shows low when I’m idling. I’ve always used the recommended 0W-20 dexos approved oil and changed it every 5,000 miles or less. Never let the oil level get low, always make sure it’s topped off. my question is, is the low oil pressure at idle normal? Or could this be a sign of a failing oil pump? Or something else entirely?

After doing some more research I think my probelm is with this part: https://www.amazon.com/ACDelco-15-74349-Original-Equipment-Conditioning/dp/B00S0JJM8O The mode actuator, not the blend actuator. If figure its the mode actuator because all my temp controls work fine, it's just going to defrost mode that prduces no airflow out of any vents besides the footbox. Looks like it could be a major pita to get to. I will start with replacing this and report back if my problem is fixed.

Reviving this thread as colder weather is apporaching again... I tried re-calibrating the system using the method above but no luck. Still no airflow when I go to defrost mode. Would this be a problem with the blend door actuator?

I have a 2018 1500 5.3 4WD. noticed a while back I that the lower oil pan gasket seems to be failing. I plan on dropping it this weekend and replacing the gasket. Does anyone on here have any any experience doing this? Any thing else I should check out or think about replacing while I'm under there? Thanks in advance.

I will give this a try and report back. Many thanks

I've got a 2018 1500 5.3L silverado. My H/VAC systems all work great, with one exception. When I select defrost mode, I notice I still hear the fan blowing, yet no airflow coming from my defrost vents. When this is happening, no air is coming from any other vents either (which is to be expected). What do I check? Is there any useful guides or viedeos out there to help? thanks in advance.