After this post I will probably be banned from BITOG. Oh well, so be it. I picked up enough PU to change the oil in my ‘04 GM SUV with 5.3L and 43K miles and my ‘09 Enclave with 3.6L DI and under 5k miles. History of the oils used in the 5.3L in order; factory fill, Mobil 1 7500, Mobil 1, Amsoil ASL, GC, and then started using AMSOIL Signature Series. After the FF only UPF44 oil filters have been used. I honestly could not tell any difference between any of the oils used except that according to the oil gauge the Amsoil products flow faster than the others. Due to mostly short trip driving and these vehicles setting for days at time without being driven, I change my oil and filters very frequently and yes, I know it is probably overkill but that is not the point of this post.
Friday evening I drained the SSO and replaced with it with PU in the GM 5.3L. On this vehicle the oil filter can be pre-filled and I do. After buttoning everything up I started the vehicle to check for leaks. I let the vehicle run for about 3 minutes and shut it down for about 30 minutes and then restarted to see if the PU flowed as fast as SSO by monitoring the gauge. It did not. The gauge moved as it had with the FF, Mobil 1 7500, and GC. Humm, oh well, no worries. While the engine was running I made note in my log of the oil change and put up my tools. Just as I was about the close the hood I heard what sounded like a lifter clack. Wow, what was that… I let the engine continue to run and sporadically I heard what sounded like lifter clacking. This engine has never produced any noise of any type so this was of concern to me.
Why I have no idea but I decided Sat. morning to go ahead and change the oil in the Enclave. In the Enclave I changed the FF with Mobil 1 7500, then switched to Mobil 1, and last October changed to PP. I drained the PP in the Enclave and replaced it with PU. The 3.6L is a quite engine I assume due to the design and the sound deadening shrouds used. However, 3.6L was a bit nosier with PP than with the FF, Mobil 1 7500, or Mobil 1 especially when accelerating. When I was about finished with the Enclave my wife, who had gone to the store in the SUV, arrived home and I could hear the sporadic clacking coming from the SUV’s 5.3L as she pulled in the garage. I was not a happy camper. I finished the Enclave and stated it to check for leaks. I could tell no difference with the PU in regards to noise from the PP. I then left for the car wash. When I retuned I pulled into the garage and a noise caught my attention. I popped the hood and holy cow I could hear timing chain noise. This was not sporadic and certainly was not present prior to the introduction of PU.
It is my assumption that once the PU washed out the oil film left by the previous oils it simply did not provide the same level of protection. Everyone else who has filled their sump with PU has raved but unfortunately I can not join that band wagon based on my experience thus far. I am extremely surprised by this but there is no reason to think things will get better.
I will be interested in seeing used oil analysis for PU when they start showing up but at this point I believe the PU in my sumps will be dumped rather quickly.
Friday evening I drained the SSO and replaced with it with PU in the GM 5.3L. On this vehicle the oil filter can be pre-filled and I do. After buttoning everything up I started the vehicle to check for leaks. I let the vehicle run for about 3 minutes and shut it down for about 30 minutes and then restarted to see if the PU flowed as fast as SSO by monitoring the gauge. It did not. The gauge moved as it had with the FF, Mobil 1 7500, and GC. Humm, oh well, no worries. While the engine was running I made note in my log of the oil change and put up my tools. Just as I was about the close the hood I heard what sounded like a lifter clack. Wow, what was that… I let the engine continue to run and sporadically I heard what sounded like lifter clacking. This engine has never produced any noise of any type so this was of concern to me.
Why I have no idea but I decided Sat. morning to go ahead and change the oil in the Enclave. In the Enclave I changed the FF with Mobil 1 7500, then switched to Mobil 1, and last October changed to PP. I drained the PP in the Enclave and replaced it with PU. The 3.6L is a quite engine I assume due to the design and the sound deadening shrouds used. However, 3.6L was a bit nosier with PP than with the FF, Mobil 1 7500, or Mobil 1 especially when accelerating. When I was about finished with the Enclave my wife, who had gone to the store in the SUV, arrived home and I could hear the sporadic clacking coming from the SUV’s 5.3L as she pulled in the garage. I was not a happy camper. I finished the Enclave and stated it to check for leaks. I could tell no difference with the PU in regards to noise from the PP. I then left for the car wash. When I retuned I pulled into the garage and a noise caught my attention. I popped the hood and holy cow I could hear timing chain noise. This was not sporadic and certainly was not present prior to the introduction of PU.
It is my assumption that once the PU washed out the oil film left by the previous oils it simply did not provide the same level of protection. Everyone else who has filled their sump with PU has raved but unfortunately I can not join that band wagon based on my experience thus far. I am extremely surprised by this but there is no reason to think things will get better.
I will be interested in seeing used oil analysis for PU when they start showing up but at this point I believe the PU in my sumps will be dumped rather quickly.
