Oil Brand Preference?

[Tony Mendez]

10w30 offers no benefits over a 5W30.

Its thicker at start up, meaning more wear.

Once warm, there is almost no difference.

If you want to clean your engine, start buying pennzoil and change it slightly more often than you typically do.

Matt, you have obviously never owned a Chev truck with a 8.1L. The 10W30 does make a difference on start up when these engines tend to develop noise from having shorter piston skirts. There is no additional wear. If that were the case I would not have 300k on the original engine.

 

[matt5112]

Thicker is worse when cold, most of the time.

Your specific example reminds me of ls1's. They now have piston slap spark modifier tables, still call for 5w30.