H-FIELD

So i decided to change the oil in my 2000' LS1 I had been running delo 5w-30 and decided to switch to Royal purple 10w-30 after reading some recamendations for summer oil and it being a heavier weight so it would have better oil pressure but imediatly after firing it up and driving it alittle i notice the lifter rattle is terrible now. when hot or cold, before the rattle was slight when the engine was cold but cleared up and was very smooth and quiet when the engine warms up. this sucks because the oil was 60+$ when normally the engine oil was less the 20$ any ideas? did I make a bad choice of oils. I always thought royal purple was supposed to be good stuff but why would the rattle be worse?

mannyman84

iTrader: (2)

Depends where you live? Is it really cold in the morning? If so you will need to go back to 5w 30. You don't want more oil pressure at cold start but better flow. And 5W flows better then 10W. Stick with 5w30 and u should be good.

2000_SS

iTrader: (24)

i've heard the stock lifters have a more difficult time picking up 10w oil. this could be your issue.

i'm sure there's 10,000 people on this board running 10w oil "with no problems," but i'm just relaying what i've heard.

Darkman

iTrader: (2)

I was not able to locate a Product Data Sheet on Delo 5W-30. How do know that the Royal Purple is "heavier" oil once warmed up? (Setting aside the startup number.)

H-FIELD

Wel it has much better oil pressure once warmed up and the lifter rattle is worse when the engine is warm then when cold so i'm wondering if the heavier oil is too heavy for the lifters? and its far from cold here in the mornig it is high 60 and almost 100deg during the day.