I have a 2002 VX II Commodore Equipe that I use as a second car, local trips, risky trips to the supermarket etc. It has just passed 230,000 KLM.
I have been changing the oil every 5,000 KLM because letting it go to the 10,000 KLM, the oil ended up very dark ( probably due to piston ring blow by or sloppy valve guides )
All this time I have been using the Castrol Magnatec 10 W 40.
I have been really happy with this in the earlier life of the car but I notice it has changed its formula over the years.
I just recently decided to use a cheaper mineral oil because I change it every 5,000 KLM.
I use a Valvoline 15 W 40, it was half the price of the Magnatec.
To my surprise, the motor seemed quieter and smoother.
I did a fuel consumption check using a full tank and again to my surprise, I dropped from the usual 10.5 to a 9.2 Litres per 100 KLM. This was a mix of both local traffic and a bit of 100 klm open road driving.
This is a big difference.
On paper a 14W40 is really no different to a 10W40.
At operating temperature, both have a 40 rating.
Could it be that the Magnatec is a semi synthetic ?
Are older worn motors better of with a thicker mineral oil ?
Does the slightly thicker oil seal rings and valve guides a little better ?
Would appreciate any informed comment on this.
Cheers All
I have been changing the oil every 5,000 KLM because letting it go to the 10,000 KLM, the oil ended up very dark ( probably due to piston ring blow by or sloppy valve guides )
All this time I have been using the Castrol Magnatec 10 W 40.
I have been really happy with this in the earlier life of the car but I notice it has changed its formula over the years.
I just recently decided to use a cheaper mineral oil because I change it every 5,000 KLM.
I use a Valvoline 15 W 40, it was half the price of the Magnatec.
To my surprise, the motor seemed quieter and smoother.
I did a fuel consumption check using a full tank and again to my surprise, I dropped from the usual 10.5 to a 9.2 Litres per 100 KLM. This was a mix of both local traffic and a bit of 100 klm open road driving.
This is a big difference.
On paper a 14W40 is really no different to a 10W40.
At operating temperature, both have a 40 rating.
Could it be that the Magnatec is a semi synthetic ?
Are older worn motors better of with a thicker mineral oil ?
Does the slightly thicker oil seal rings and valve guides a little better ?
Would appreciate any informed comment on this.
Cheers All