Top Tier Gasoline vs. Diesel
 

Since my first "premium" new car in 1995, I have ALWAYS used Chevron Supreme gasoline (per the recommendation by my Mercedes and BMW Service Advisors).

Now that I have a Diesel, does it matter? There is a Chevron somewhat close to my son's school, but not close to home, that has Diesel #2 (new station, great pumps, family owned...).

Very close to home, is a Shell station that also has Diesel #2. I have NEVER used Shell gas, as it always seemed "cheap" and inferior to Chevron.

Is Diesel fuel top tier rated, as gasoline is? Is Shell Diesel the same as Chevron Diesel? Also, the Shell station is consistently 5-10 cents a gallon less than Chevron Diesel and gasoline.

I need to diesel up in the next few days, and since my son is out of school for Christmas Break, I do not know whether to drive to the Chevron station, or just go around the corner to the local Shell station!

Also, I know part of my OCD :) , but I never have mixed brands of gasoline. I always think since Chevron has Techron and 76 or Shell do not...it will cause a problem. If I use Chevron Diesel, and then for some reason do not have time to drive back to Chevron for the next fill up, can I use Shell or Union 76 Diesel? Does it matter in the slightest bit??

Thanks a lot!!

I have used Chevron and Shell interchangeably for the entire 13k miles I have owned my 35d. Both are top refiners and maintain very clean stations. Never had a problem. I personally would not fuel up anywhere else.

By law, in California, all stations must meet a certain level of Cetane content in diesel. So, if you only judge by Centane content, it really doesn't matter where you fuel up (only applies to CA.) But I only trust Chevron and Shell for my 35d.

I can't really comment on the diesel fuel situation in the US but BMW does specify a minimum cetane number for its diesel engines.

Not to the extent that you are worrying about it.

You should buy diesel fuel from a name brand supplier, who does a reasonable volume. Brand matters little, if at all. You can look up cetane ratings if you like, but what the state mandates as a minimum should be fine.

A station being clean, with clean pumps, is enough of a reason to use them. If you notice a difference between one fuel and another, then fine, use the one you like. You should know, though, that much of the fuel comes from the same distributors, no matter which station you use.

Nothing wrong with Shell. I like Chevron (used to work there, like Techron a lot) but Esso and Shell are fine. With gasoline, all the majors either use Techron, or have an equivalent additive. Shell has really good advertisements with Ferrari race cars, which I think about when I fill up at Shell.

Top Tier has no applicability for diesel. Top Tier itself is not a quality designation, they have just done so much marketing that people tend to believe that it is. It only applies to gasoline, and all it means is that there is sufficient quantity of the additives that prevent deposits on valves. It doesn't have any bearing on fuel cleanliness, octane, water content, ethanol content, or any other property associated with quality. It mattered far more a few years ago, when some low-grade gasolines did not have sufficient additives to prevent deposits. These days, that is far less of a problem. I use Top Tier most of the time, but I wouldn't drive across the street for it if a station I used was on the right side of the street.

Thank you for all the replies. My last diesel was a 1993 300D and a 1983 300TD...and I did not care where or what diesel I put in them. With the new X5, I care! ;)

Again, thanks! Merry Christmas!

Well, you have moved up a little in technology. Those were good engines, though.

Merry Christmas to you.

All diesel fuel sold in CA meets BMWs spec for 'premium diesel cetane'.

Now, in terms of the other stuff in diesel fuel that provides for lubricity (ie good for your fuel system, pumps, injectors), there is virtually no way to know what is being sold... websites, links, marketing claims, etc... but in terms of "premium diesel" it is almost unregulated.... There are minimum standards, and then that's it- all the rest is hype and trust. Folks seem to think "Oh, they are a Top Tier gas company, must be top tier diesel too"

Just spent about 20 minutes on Shell and Chevron's websites, and read about their diesel fuels. Besides our great weather, California is the ONLY state that only allows Ultra Low Sulphur Diesel (ULSD) to be sold. All other states must say in writing if it is Low Sulphur (LSD) or Ultra Low beng pumped. Using LSD in our new BMWs can ruin the emission controls and damage the engine. Scary if you are on a road trip, and are unlucky to be in a state with only LSD, and not ULSD!

What do you guys do, who are outside CA? Is it hard to find Ultra Low Sulphur Diesel? Both Shell and Chevron said it is mandatory to use ULSD for any 2007+ diesel passenger vehicle.

Chevron's website does talk a lot more about their diesel being as clean and top notch as their gasolines, compared to Shell!

I havent seen any LSD in Arizona at all, but then again, given my other car is an 06 dodge diesel and it doesnt care what i put in it, i dont look too hard.

I use top tier, high volume stations...other than that, not too concerned...and in a pinch i'll use what's available without much concern.

Interesting that you mention the sulphur content issue. Here in Australia where we have various E53 and E70 diesels since 2003, many of the updates with the diesel engines (and there's been lots of them) have coincided with a reduction in diesel fuel sulphur content according to the Australian government mandates. Over the last decade the mandated maximum sulphur content has dropped from literally anything to 5ppm in a series of steps. From memory it first went to 500ppm, the 50ppm (we call that LSD) to 5ppm (our ULSD).