Hi I always use millers oil,this is my 3rd Impreza but my 1st type ra and have always used 10w40. I have recently notice people on the forums saying they use 10w50. Would this be the preferred oil for my ra?
Cheers Rich

 

RCM recommend 15w50 or 10w60.

I use 10w60

 

Depends on how you drive the car.... Road, track?

 

Doing more reading and looks like there are few different opinions on this and most answers are right or at least not wrong,different strokes for different folks
I guess there are a few correct options.
It's my daily driver so mostly road use,I will probably have a few track days further down the line.

 

It really comes down to how modified the car is. The more modifications to the engine, the hotter it runs, leading to the oil becoming thinner. A few minor mods will mean there is no need to use a thicker oil than standard. A heavily modified car might need a grade or two thicker.

Cheers

Tim

 

It also depends on the build spec of the engine, a full race engine with 'slacker' bearings needs thicker grade oil.

 

Some good answers there making it a lot clearer for me to understand. Cheers guys