[jstapertfam74]

A month or so ago, I purchased a 2010 GL 350 Blue Tec. I have two questions:
1) This evening it is probably 45 degrees F in Indiana. I drove the truck home from a restaurant approximately 20 minutes away. When I pulled it into my garage and shut it off the electric radiator fan was running. It ran for approximately 10 minutes. I have not heard it running at all in the past especially after shutting it off. There have been 75 degree days when the fan has not run at all when the truck was shut off. Is this normal?

2) The oil was changed when I purchased the truck (or at least that is what we were told at a dealership). I just checked it and it is very black on the dip stick. They supposedly put Mobil 1 in at the change. I have never had a diesel before. I have put approximately 2500 miles on it since the change. Should the oil be very black in this amount of miles?

Thanks.

 

[KipF]

No idea about #1 other than you may want to check and see if you have residual heat turned on.
Re: #2, yes, the oil will turn dark pretty quickly. It's the same with all 3 of our diesels. Nature of the beast - nothing to worry about.

 

[jstapertfam74]

KibF, Thanks for the reply. I did check to see if the residual heat was turned on and it wasn't. Since the residual heat relies on the warm temperature of the antifreeze, it would seem counterproductive to run the radiator fan to cool the antifreeze down while trying to pull as many BTU's out of it as possible. Since this is the coldest evening that we have driven the truck, I am wondering if the thermostat controls keep the engine at a higher temp to run better when it is cold??

You obviously have a lot of experience with diesels. What frequency do you actually recommend for oil changes? And, how often do you totally change out the Blue Tec fluid instead of just adding to it?
Thanks.

 

[KipF]

I did a little research and I'm certain someone here can clarify, but I read that the fan runs to remove/reduce condensation in the HVAC system and vents. Some dealers are saying it is a "feature" of the car. Our GL's are an 08 and an 09 and I don't recall either of them doing this, but it could be I just haven't noticed it.
I change my oil every 5K on everything. I grew up doing it, and probably always will. Your service indicator will tell you when/what is due though. Depending on your driving habits, you may need a service based on time rather than miles. I think MB recommends every 10K. You will need to add AdBlue (DEF) fluid every 10K. It's not something that gets changed, it's a consumable so you just use it up. If you do it yourself, it's less expensive to get it at an auto supply house or even the VW dealership. Just be careful if you add it yourself not to spill as it can cause damage to the wiring below. I keep a small container of it in the back that I picked up at the VW dealer just in case I was on the road and the AdBlue light came on.

 

[TCC&D]

It seems you are talking about two different fans. The radiator cooling fan and the interior ventilation fan.
I've put 290,000 kilometres on my 2010 GL350 and many times the rad fan stays on after the vehicle is shut off, presumably to complete the cooling process. Always goes off in a few minutes.
Critical spec for motor oil is to make sure it's meets 229.51, not just 229.5.
I drive all highway kilometres so computer calculates oil change at 15,000 kilometres.
I fill ADBLUE tank at FLYING J truck stop. Just pull up to big rig pumps and fill until it runs out on my shoes.

 

[jstapertfam74]

KipF: Thanks for the great advice. I was thinking 5K miles also on the oil changes as that is what I do with my gas engines. Keeps it simple.

TCC&D: 9300 miles is a little scary for me to wait to change the oil. Maybe I will be brave enough one day to wait. For the first change, I am planning on taking it to a MB dealer because I purchased the truck from a non-MB dealer. After the first change, I plan to do it myself so it won't be too costly to change more frequently.

Concerning the rad fan, yes this is the one I am writing about. By chance have you noticed the fan running more in colder weather than in warmer weather after you shut your vehicle off?

 

[nynd]

The fan running is normal. Sometimes you may also smell something and what that is are the rear scr cat's burning themselves off of contaminants. During this, you'll notice the fans are running upfront as well.

Oil, it is an easy do it yourself. You can purchase a MITYVAC too and extract the oil with a suction. You can do this from the engine bay, so no need to get under. Filter is right there as well if you want to change that. You may also want to see if the diesel filter has been changed. This is probably more critical of an item for longevity.

 

[jstapertfam74]

nynd - Thanks for the info. That is exactly what we experienced last evening when my wife pulled the truck into the garage. This is the second time we noticed the fans running (the first time is when I wrote to this forum originally). This time we noticed that something smelled hot, so this is right in line with your description.

Concerning the filter, are you writing about one filter or two? I assume that when your write "Filter is right there" you are writing about the oil filter that I have been told is under the engine cover. Is that the same as the "diesel filter" because that sounds more like you are describing a fuel filter? If that is a separate filter, can you tell me where it is located and if it is easy to change? I know I am proving what a novice I am with these questions, but I have to start somewhere. Thanks.

 

[nynd]

Sorry for the confusion. Regarding filters - the air filters are located to the left and to the right of the engine. You need to remove some of the intake hoses (from ontop) and then get your hand down in there and unscrew the covers. Once this is down, you can slide out the air filters.

For the oil filter, that is right on top and you'll see a plastic black circle cap. All you do is unscrew that and pull out the oil filter and replace with the new one. You'll also get some o-rings include so swap those out as well.

For the diesel filter, if you did the air filter, and have removed the top cover, you'll see the diesel filter (fuel filter) sitting more or less in the middle of the engine (looking from the top). It has two hoses connected to it and a water sensor inside it. You can probably find a Youtube video of someone changing one. You just need to make sure you unplug the fuse (to the fuel pump) or disconnect the negative on the battery (under the passenger seat). This is to make sure the high pressure does continue to run when you remove the hoses. There are clips and two sets of o-rings you should purchase as they don't come with the replacement filter. The parts guy will know which they are when looking at the assembly (they are for the water sensor which you remove and re-use) and the clips are for the main two hoses. Once you've installed the new one, you need to put back the fuse (or connect the battery) and then just turn the ignition on (not start) the vehicle to listen for the diesel pump to build pressure and prime the filter (as the filter will be empty). You do this a few times and let it prime for 30 sec or so. Check for leaks, if your good, start it and check once again.

Finally, there is a set (2) of cabin filters which are accessible from the engine compartment as well. On the passenger side near the firewall, you'll see this vent type thing that mates with the hood (when the hood is down - where air enters). There are two metal spring clips which you can remove and pull upward on the plastic housing. If you look inside, you'll see the two filters sitting side by side. Good idea to change these from time to time.

Hope this helps!

 

[McGG]

Glad I cleared up the fan noise in the cold and the engine smell thing. Thanks for the great info.

My fan stayed running a few days ago, much to my surprise, as it was -30 out at the time. Yes....minus 30.

 

[jstapertfam74]

nynd - Thanks for the great filter info. I printed it off and will use it when I start playing around with the changes.

McGG - If it ever went down to -30 in Indiana, we would all think the world just came to an end and would not worry about our MB's - LOL. MB must put good batteries in their vehicles.

 

[Tobgay]

GL 350 Bluetec, changed the battery for the vehicle and now it displays "SRS and Front right side malfunction"

Please help, any idea on what it could be.