5-30 in winter, we see -40*c some nites, and 10-30 in the summer +35* days. The old ranger has 260000 kilometers on the ticker, so i can' be doing any harm to it. I have read that manufactures spec such a low weight oil so that they can obtain high mpg estimates, and still provide protection to the motor.

Im a mechanic and I reccomend 5w30 in the Winter and 10w30 in the Summer. If you do this your engine will be lubricated right for the changing seasons. High mileage is definantley the way to go, if you have ever thought about it I FULLY reccomend Synthetic, this helps prevent and seal leaks it is also specially formulated to help your engine be better lubricated. Still though even for a High Mileage or a Synthetic I reccomend 5w30 in the Winter and 10w30 in the Summer.

My owner's manual says that for 2.3 & 3.0 engines, you should use SAE 5W-20,
and for the 4.0 engine SAE 5W-30 is recommended.

I have the 2.3 engine so I use 5W-20.

Actually this is completely wrong and BACKWARDS!!!!!!!!!!!!

High mile oil and synthetic oil in the same sentence meaning the same thing is like comparing apples to oranges.

If you want to REDUCE oil consumption/burn off or even MINOR leaks you most definitely want to run NON SYNTHETIC!!!

Scientific proof from a 3rd party analyst??

LMAOOOOOOOOO

It does not take a rocket scientist to know that running HIGH MILEAGE/thicker NON SYNTHETIC oil will REDUCE oil consumption and burn off and even slow down or stop MINOR leaks.

Common sense my friend!!

If you took two identical trucks with equal engine wear ( lets say 240,000 on the odometer ) and both trucks were know to ( USE OIL ) between oil changes and maybe had a minor leak around some gasket and you emptied the oil in each truck and in one truck you put in ( FULL SYNTHETIC ) and the other truck you put in ( HIGH MILEAGE OIL/NON SYNTHETIC ) and ran each truck for 5.000 miles I " guarantee " the truck that uses ( NON SYNTHETIC ) would show MORE oil on the dip stick!!!!!!! PERIOD

That is quite a guarantee...maybe you should make your own product. Just wondering if you had facts, guess not.

:bigeyes2: ^^^ :popcorn:

Not saying the guy is wrong or right...just wondering where he got his FACTS from, not opinions. He seemed pretty confident so I was just wondering.

Everyone here needs more that "Its common sense my friend" what does that prove?
Did you know that synth will break down less over time? So if you use a non-synth, your oil will break down faster, limiting its lubrication qualities. I am not saying run your oil for 10,000 miles, cause the filter generally isn't good for more that 6-7000, but think about it.

Couldn't have said it better.

I will believe science over some guy on the interwebz any day, sorry

I will still be running Mobil Full Synthetic until someone can convince me otherwise with scientific proof. I change my oil every 3000 miles.

I work at Jiffy Lube Currently and I had to take trainig sessions on oils and viscosities so I do have facts and proof, at least 300 satisfied customers. "Common Sense My Friend"

x3.. never had ne problems with running it

I just changed my oil the other day. I got Penzoil high mileage 10w30 with a purolator oil filter to run through the summer then I will switch to 5w30 in the winter. I also used that restore stuff for V6 engines, has anybody used this?

Thanks for the advice guys