Shell Ultra vs. Petro Canada diesel

Has anyone noticed a big difference between these two fuels? Importantly, has anyone noticed that the Shell fuel is badly inferior? I had a really, really bad tank (only 550km) from Shell. The next tank was from Petro Canada, which happened to be the only station open late, and I was 500mL away from an empty tank. The next tank, driven under the same conditions, got me over 740km. I filled up at shell for my next tank, and it looks like it's going to give me another lousy one.

I just want to know if this is something that other people have noticed, or if it's just the station, or a certain batch, or what.

I prefer Shell for completely lazy reasons, ie. a dongle that I can attach to my keychain to make paying faster and easier. If the fuel is that much worse, though, I'm gonna be a little less lazy and head to PC.

I just had my car for a couple of weeks. But for what it worth, my last 2 tanks were filled at PC and the first gave me a solid 792 KM and the last one a ''not too bad'' 820km both in the same driving conditions. Will go test the Shell stuff on my next one (i need to go get some air miles anyway..)

You're a long way from me, and I haven't used Shell fuels for a long time (biodiesel available here, and Sunoco before that) but my car always ran very nicely on Shell Diesel and Shell Ultra Diesel. I don't think I've ever put PC in the tank because about three years ago, when I was hanging around TDI Club frequently, it was mentioned as a place to avoid. There have been a lot of refinery improvements since then, and the introduction of ULSD must have done a lot for fuel quality from all sources.

Don't forget that diesel fuel formulations change throughout the year for lowest expected temperatures and its about now that the BTU content of the fuel starts to rise again leading to better fuel economy.

Interesting, I tried the refinery row FlyingJ (supplied by Shell) a few weeks back. Mostly highway miles and had about a 10-20% reduction in mpg's verses the local COOP diesel.

Luckily FnJ's price was about 10-20% less than the local COOP. But then again, we usually get a 6-10% rebate from the COOP at the end of the year.

Next time I'm by the FnJ I'll try it again, nice to have a bit bigger sample size.