Diesel oil is always dark from soot. It has a distinctive smell to it too.

I just changed mine this morning, then spent the entire afternoon changing out the glow plug module. That was a bit of a PITA.

Were you getting glowplug fault code?

Yes. When we bought the car we were informed that there was a fault for glow plug #4 or 5 (can't remember just now) and that the plug had been replaced and the fault remained. So that pretty much points to the module being bad.

Given that the thermostat was also failed open, and the additional duty that the cold running engine puts on the glow plugs has caused failures before, based on my research.

The module is buried under the intake, under the coolant pipe that bolts to the block. If you remove the coolant pipe, I'm sure its much easier. But otherwise it requires snaking things around and the hardest part was unplugging the connectors with no room to work.

07.14.17 - Glow Plug Fault Fixed/Repairs

Brought the 35d to the stealership last week for service. After research, I decided to let someone else handle replacing the glow plug module. I don't have the space at my apartment to take everything out and drain the coolant, etc. Parts were cheap enough:
$130 for the module and $60 for plug. The labor was just under 4 hours (3.8) so everything all in all was $600.

I've been religiously check the tstat temps, and everything seems to be in working order. I expect to see a slight increase in mpg now that the glow plug fault has been fixed.

11.09.17 - Been awhile

So it's been awhile, guess that's a good thing! The 35d has been great so far. Wife is racking up the mileage on this thing. I performed another oil service on the torquey beast back in Sept. I also refilled the vehicle with DEF - it took all 2.5 gallons!

As of yesterday, I added about 8oz of power service (white bottle) to the gas tank. Temperatures are dropping around the Washington DC area. Tomorrow should be in the 20's when we wake up. I'll add another 8oz after the next fill up. Current mileage is 65,750

Next up:
[ ] New tires - most likely going with Conti DWS06. I am a little curious to try out the new Michelin A/S3 N-Spec, they are a couple hundred dollars more though.
[ ] Cabin filter replacement @ 66,900
[ ] Air recirc filter @ 66,900
[ ] Intake filter cleaning due up @ 66,900.
[ ] New front cup holders - they were broken when we bought the vehicle. It's not a huge priority at the moment but it annoys me when the beverages move around in place.

I have the Conti DWS06 and love them! They don't hydro plane at all, and as far as winter grip, they are not to bad!

Hey man - Wife is still loving her DWS06's - She just rolled 61k as we had a wicked amount of trips lately (3 trips back and forth to Florida with the dogs) -

But it will be sitting more for a while, ready for another oil change with T6 this week, and I'm just about due for a fuel filter service too so I'll have to figure out if I want to pay the dealer or DIY -

Been running like a champ though, wife loves this car, no complaints! I can get it tuned a BPC in Raleigh with all emissions equipment in place and gain another 100 ft lbs and 80 hp, if I stop buying guns for a bit maybe I'll do that for her although she loves the truck the way it is LOL