Death Rattle

pdr

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Just wondered if any one has run across having changing oil Moble synthetic 5-30 in a 03 LS 3.9 on cold starts and I live in Hawaii there is a horrible bearing sounding rattle for just about 2-3 seconds then gone all day till about 8-10 hrs. of sitting and it does it again. 107,000 MI. just happened right after oil change . Not like this was slowly coming on . Just came on. Sounds real bad for those couple seconds then runs great other than all the other problems I read about on this Forum. Anyone use additives like Lucas . Getting ready to change oil. Thanks in advance for any help.
 
Are you sure that it's not the cam synchronizer(s)? I'm pretty sure that was the source of the start-up rattle that my 04 started having around 220K miles.
I switched away from Mobil-One a few years ago. I'm sure it is fine, but there are better oils for the same price. Mobil-One always tested out at the bottom of the viscosity range for its stated weight. Note that the correct weight for your engine is 5W-20 or 0W-20. Despite the popular theory (with no backing), thicker is not better. If you've been using that weight for a while, the increased pressure may have damaged some of the seals, causing the synchronizers to leak out their oil while the engine sits.
If it is the synchronizers, it should be functionally okay for a long time yet.
Also, make sure you are using a good oil filter. The check valve can allow leak back on the cheaper ones. I had/have good luck with Wix, but I'm sure there are plenty of other good ones.
 
first make you sure you have a working oil filter. an fl2021 is like 4 bucks
Note that the correct weight for your engine is 5W-20 or 0W-20. Despite the popular theory (with no backing), thicker is not better. If you've been using that weight for a while, the increased pressure may have damaged some of the seals, causing the synchronizers to leak out their oil while the engine sits.
all oil is much thicker when cold. the difference in oil pressure between 5w30 and 5w20 at operating temperature is not significant. regardless more MOFT = more protection.

the designers of the engine did not use 5w20 on their own cars because american fuel economy tests were not important to them
 
Motorcraft filter? Not sure if the filter has an anti drainback valve or not on this car. When I had the 99 Continental I started using Motorcraft only because of longer noisy starts from the others.
 
Motorcraft filter? Not sure if the filter has an anti drainback valve or not on this car. When I had the 99 Continental I started using Motorcraft only because of longer noisy starts from the others.
Yes, the correct filters do have an anti-drainback valve. You can see it looking through the outer holes.
 

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