Time for another oil change, time for another oil question.

I was looking at Shell Rotella T6 and I noticed that it is offered in a 5W40 and a 15W40. Which one should I use? I also noticed that since T6 was offered in a 15W40 so I started looking at other 15W40 oils and saw there was a Rotella T5, which is a synthetic blend. Is it better to go full synthetic of a blend at high mileage?

I'm coming up on 190k miles and I live in North Alabama, so it doesn't get very cold in the winter.

 

I prefer the T6 15w40 in my V8.
But honestly any oil is good as long as you change it and the filter regularly.
Actually, I was thinking of trying out the Amazon oil on my next oil change.

 

hahaha I was thinking about it to, I put the Amazon stuff in my wife's Ford Escape.

 

I think when it matters is when temps drop in winter to -10-20 Celsius. You want that 5 w grade

 

 

Use the 15w in your neck of the woods, if you drive less than 20mins regularly, change the oil every 5k. If you drive more than 20mins, you can extend the oil changes if you run synthetic, but I prefer more frequent changes.

 

I’ve been running the Amazon oil in my Excursion seems fine and the V10 is happy

 

Anybody else use STP oil treatment (ZDDP)? My truck likes it quite a bit with Rotella T5.

 

Since watching a video from RPI Engineering I've been running what they suggest which is

• High zinc/phosphorus for anti-wear protection, including push-rod and flat tappet applications

Valvoline 20W-50 VR1 Racing Motor Oil

 

personally I can’t tell by engine noise or power etc what oil is in there. I would like to hear how you can tell your engine is happy by what type of oil you put it