Hello I'm getting conflicting information on what motor oil to use for the 2006 Chevrolet Uplander 3.5 LS. The owner's manual says 5w 30 but when I go to a auto parts store like AutoZone O'Reilly's or Advance Auto parts to put the correct type of motor oil they all pull up synthetic oils?
And is it true if you change to a synthetic oil you have to continue using a synthetic oil which I've heard a lot of Auto parts say?

 

A synthetic or synthetic blend of the proper weight will be fine. For an 06 probably a high mileage oil selection as well. I buy whatever decent brand is on sale; have 350k on the two cars I maintain

 

Thanks, so what about when someone changes to synthetic blend they have to continue to use that and can't go back to conventional oil ?

 

You can switch back & forth from synthetic to conventional. Conventional 5W-30 is all that is required (what was put in the van at the factory). Get some Walmart Supertech or whatever is on sale.

 

i remember hearing something about synthetic doing something to the gaskets/seal and if you go back it will cause leaks. i dont really remember seeing any facts on this

 

That's just a myth. You can switch between the two at any time. If cost is a concern, Wal-Mart Super Tech Full Synthetic is an excellent synthetic oil. Testing shows it outperform many of the well known name brand synthetic oils.

5W-30 is the same viscosity whether it's conventional or synthetic.

I've worked on engines that have been run on conventional oils and synthetic oils. The synthetic only engines are always perfectly clean inside where as the conventional only engines varied from slight buildup to massive buildup of thick oil deposits.

 

I have a 2006 Chevy Uplander LS 3.5, it has a bad Neutral safety switch, so when in park it does not identifies that it is in park there for it won’t crank, any solution or may it be something else instead of yhe actual switch

 

desperately need help on this

 

Juan you will have more success starting a new thread vs jumping on this old one