fmblizz

My engine temp usually runs in the area of 205. I've been dealing with this for like I said 3 years. I don't clear the code because the code clears itself after a few days.. The agency I purchased the truck from wanted to replace the oil pump at a cost of $2300 and that was 3 years ago citing I could be damaging my engine. Oil pressure seems to be running high all the time but as long as I have pressure, and I watch it like a hawk, I'm not spending the money which is now in the $2600 range I'm hearing. Maybe I'll look into the thermostat at some point but I've always been a believer if it's not broke, don't fix it.

My 2014 Silverado which I purchase new, has been throwing the P066DD code intermittently for 3 years now. I have no performance problems that I can tell. My engine is the V6. With the Check Eng. Light on the engine will not drop into the V4 mode. After 50-100 miles of driving it will again start to drop into the V4 mode and shortly after that the code will clear itself. This will only last for a few days at which time the entire cycle repeats itself. It's almost like clockwork. I do regular oil/filter changes and my oil pressure is consistently between 45-55 psi. My problem is that in the state of NJ and Check engine light will fail you for inspection so I have to time it right.. LOL Any thoughts would be greatly appreciated.

Did you ever stop to think we maybe talking about two different issues... Don't be so quick to say BS.... Have never had any issues over 50 MPH like other do. Also why would my vibration always and I mean always be when the truck is dropping cylinder.. I can put it on the cruise control when it starts and the vibration continues until the computer tell the truck to go back to normal V6 mode and then things smooth out again. Have never felt any shutter except when the RPM's are 1200, and the truck drops the two cylinders and my V4 indicator come on.

99.9% sure it all has to do with the AFM "active fuel management" system.. in every instance, the engine is going from the V6 mode to V4.. Blizz

Is it possible for this V6-V4 issue to get worse by driving the vehicle. My 2014 only has 18000 miles on it. I didn't really notice it until this past month and I feel the vibration is happening more and more. Always around the 1200 RPM area.. I can even set the cruise control when I feel the shutter start and it will continue to shutter for a bit before finally kicking in the two dropped cylinders and going back into V6 mode. I hope there is a quick fix because I'm not going to live with this situation on a $42,000 MSRP truck. blizz

My 2014 Silverado Z71, 4.3L V6 has a vibration at 30MPH, 40MPH and 50MPH.. It comes and goes.. I have put the speed control on as soon as I feel it and the vibration will continue for a bit and then disappear. If I accelerate or decelerate 1-2MPH the vibration goes away. The one thing I did notice is that the RPM's when I start to feel the vibration for all 3 speeds is consistently around 1200 rpm. The truck was fine until I took it in for a service update 2 weeks ago.. Does this make sense to anyone?? Almost feel like it is some type of shift point problem.. Blizz

My 2014 Silverado Z71, 4.3L V6 has a vibration at 30MPH, 40MPH and 50MPH.. It comes and goes.. I have put the speed control on as soon as I feel it and the vibration will continue for a bit and then disappear. If I accelerate or decelerate 1-2MPH the vibration goes away. The one thing I did notice is that the RPM's when I start to feel the vibration for all 3 speeds is consistently around 1200 rpm. The truck was fine until I took it in for a service update 2 weeks ago.. Does this make sense to anyone?? Almost feel like it is some type of shift point problem.. Blizz