On a slightly different note...I think since I made the switch to Royal Purple synthetic oil my mileage has improved slightly,about 2 MPG around town! I recently went from Mobil 1 to the Royal Purple because a good friend said the same thing about his mileage.Or maybe it's just because the planets are in alignment.

 

HB- How many miles on your HHR before you made the change to M1?



Goose

 

Goose...I bought mine from a rental fleet.It had around 26K when I got it.Got a great deal that way.I switched right away to M1 and about 2K ago changed to Royal Purple.I have heard that you should break in with dino oil for about 3K before you switch to synthetic. :http://www.royalpurple.com/prodsa/rpmoa.html

 

I switched to M1 at 5K. Mileage did not increase..... I use a 10K interval on my wifes MPV and tested, the oil was still within tolerances. So I stick to that. For the HHR, I'll let the DIC let me know. Oil companies are already getting too much money from me, I'm not going to volunteer more with 3K oil changes. Those days are long gone. Even using dino.

 

I agree. I did the first change at about 5,000 kms/3,000 miles because I wanted the break-in oil out of the motor.
The second run I did on dino I ran it to about 8,300 kms/5,000 miles (about 24% oil life left).

By the end of that run, my MPG was starting to drop off and the motor was feeling sluggish, so I switched it out for synthetic when the mileage on the car hit 13,000 kms/7,800 miles.

I'm going to run the synthetic as long as possible and send a sample away for analysis. It will be changed out for fresh synthetic before winter arrives.

My plan is to have two oil changes a year.

 

I changed more often when I lived in Montana and Eastern Washington. Thats another thing to remember for those living up north. Condensation from heat up and cool downs. No two areas will probably see the same "mileage" between changes on average. Here, mild winters are less stressful, but the heat from the summers will cook. I can't remember the exact numbers off my head, but after 10K miles the 3.0 DOHC in the Mazda was about 24% or something like that. 15K would have been pushing it and 10K was making me go . But I held on and sent for the test. Only did it once, but it was enough to let me know I was good to go.

 

I avg 500 miles per week so my oil changes come a lot quicker than most folks do. Valvoline dino in there right now until 4100 miles (changed out at 1100) If I stuck to 3K changes I'd go broke! Even so I will do one more 3K run with dino and then maybe switch to synth. Will be hard to do though...I have quarts and quarts of dino in my garage lol


Goose

 

If it's the right weight, I would just run that and switch to syn when you run out. Your not going to hurt anything changing later.

 

That is prolly what I will do...my wife will kill me if I start to hoard oil again



Goose

 

I changed mine to full synthetic at 2979