ULTRA LOW SULFUR DIESEL for My Q5 TDI
 

Hello Everyone,

I got my Q5 TDI one week before and now its ready for its first diesel refill. I live in Houston, TX and wondering whether anyone has a recommendation on which Gas station to use for low Sulfur Diesel based on the quality? Like Chevron Vs. Shell Vs. Exxon -Or is all the same and just pick one based on the price?

Also is there any benefit trying to stick with one vendor i.e Shell and try to use same chain every time you refill?

Thank you very much in advance - Below are some pics of my sweet baby Qufffeeeey :p

It's virtually the same product regardless where you shop. I try to buy my diesel fuel from locations that sell a LOT of fuel.

It's all ULSD.

Luckily, being in Houston means that you have no cetane-related concerns since Harris County is covered by TxLED which mandates a minimum 48 cetane. ULSD is a requirement nationwide and has been for years, so any passenger diesel you get will be ULSD so the sulfur content's not a problem, either.

Brands tend to matter less than with petrol (especially within TxLED counties since they'll have the same cetane) as the biggest problem with diesel is water contamination. To combat that, you ideally want a station with a lot of turnover in their diesel tanks, and good drainage so there won't be water pooling near the tank access points. Just look for a clean station that hopefully has a bunch of diesels filling up at it and you should be good. Personally I wouldn't trust a Murphy or similar "discount" station when given the choice, but I don't know if there's really any logical reason to avoid them other than bias. :D

Personally up here in Austin I tend to fill up more at Chevrons or the occasional Shell, but it's a combination of location convenience, how quick it is to fill up (my preferred station is a Chevron where all pumps have diesel nozzles), and whether the station seems like it's well-maintained (less likely for water contamination and leaky/dirty pumps).

Sticking with one brand doesn't necessarily mean much, but for consumption-tracking purposes it's ideal to try and use the same station, and same pump if possible, just to be somewhat confident that the auto-shutoff is stopping at the same place from tank to tank. If you switch stations all the time then individual fillups won't be accurate (later shutoff = lower calculated MPG, earlier shutoff = higher calculated MPG), but your overall average will be. One other reason to stick with a station is trust in the product, but most likely any major station there should be fine, we've got a lot of diesel pickups in the major cities, in addition to the typical box trucks. :D

Another tip: you may run into a diesel pump with a nozzle larger than what the Q5 TDI filler neck will accept.
VW/Audi sells a funnel-like adapter (part number 000-072-709; circa $9.00) which allows use of any size nozzle, including semi-truck size. It's come in handy for me a couple of times already ...

Just make sure you don't put biodiesel in it. Maybe not an issue where you are, but in the midwest you have to be selective, and in Illinois it's hard to find regular diesel.

And +1 on the adapter- ran into one station in DM where I needed it, and just avoid that station now anyway.

One a recent road trip to and from Arizona, luckily didn't find much biodiesel...


BTW, I think you just took pictures of our Q...

Like with petrol, it's hard to avoid the low-percentage blends (B5 is what everywhere has around here), but you definitely don't want anything higher than B5 or you'll end up having problems since the system's not set up to handle biodiesel.

I agree with most of the above. Working in the industry there is virtually no difference between distillate fuels and marginal diffference in gasolines. Most of the base stocks are just simple refinery grade.

As for biodiesels, stick to someplace that sells b5. That level of bio is actually helpful to engines as it has addtional lubricity charactoristics which only help seals, rings and such. beyond b5 though you start to lose some of the energy properties.

Thank you all for your valuable feedback - I will definitely ask my dealer for the funnel-like adapter (part number 000-072-709) before our next road trip.

get the adapter on amazon etc.