What are your opinions on the proper type of oil to use?

A: What viscocity (dealership said 5W30 of any oil, but a mechanic friend says synthetic 10W40)

B: Synthetic versus traditional oil.

I live in the mountains of Arizona where the weather hits single digits in the winter and the 40's in the afternoons. Summer temps range from the 60's at night to 120's in the summer at lower elevations (two hours down the hill). Any advice or words of wisdom?????? Thanks

 

I live in New England and run Valvoline Max Life 5w-30 High Mileage conventional (I think its conventional). No issues with it in the cold or heat, but I am not at your extremes.

 

One suggestion I have is to use lucas oil with every oil change. I have used it for 2 years now and can feel a differance for the first 1000 miles or so. My buddy also has a 2001 5.9lt Ram with over 200,000 hard miles on it. He uses it at every oil change and the truck still runs like brand new. I am sold on Lucas products.

 

Synthetic oil has been proven in test after test to be superior to conventional oil or syn blends. Since you get what you pay for, it cost more. You can pm me for a list ot websites for oil test results and a discussion of oil, oil treatments and fuel treatments.

Dusty

 

I just swtiched to the new Mobil synthetic, the one w/ 15,000 mile change intervals... I can definitely tell a difference... It's 10W-30, which is what is recommended in the owner's manual... If you live in a high heat area, you can go to a 5W-30, trust me, where I live, even that can be thick, but unless you see consistant 100+ degree heat, I wouldn't recommend it... I'd stick with the 10W-30, or maybe even stepping up to a 25W-40 weight, especially if you have the 5.9 liter (360cid)...

 

So let me ask this, is Stright Syn enough better then Syn blend to warrant the differance in cost? I have been running the blend in everything I own for years now, my boss swears by Mobile One Stright Synthetic. So just wondering if it is that much better to go ahead and switch over? Is there any issues going from Blend to straight on a 130K motor, it doesnt use any oil or leak, but just making sure before I go ahead and make the switch.

 

Can you mix the Lucas with the syn oil?Im sold on Lucas too but never tried synthetic.