DennisG01

Hello everyone! I'm considering an '08 GL 320 with about 62K miles. I've been lurking for a bit and enjoying reading the various threads. I've got a couple questions and I tried searching first, but was unsuccessful... although I could be that my searching skills aren't that good!

-- Is there a "common problems" thread (areas to focus on when checking a vehicle out)? I have 'googled' and come across things like air suspension and oil cooler seals. Anything else? I realize any used (or even new, for that matter) car can have issues - just wondering if there's any recurring problems that are common to the GL, in general, or the diesel engine.

-- I'm familiar with diesels and the general maintenance involved... fuel filters, glow plugs, etc. Anything else specific to this diesel?

-- I've always used an additive for lubricity, cetane improvement and fuel quality in my other diesels. Do you guys/gals do that, too, with this engine?

-- I try to do most of the maintenance and repairs myself. When it comes to something like resetting a "service needed" type of light/warning, are there ways to do that at home without a fancy computer? For example, in my '97 BMW 528, I can short certain pins together in the engine-bay mounted OBDII port.

Thank you for any insight you can provide! Again, I did try searching for these questions first, but wasn't able to find anything. I apologize if I'm asking questions that have been answered many times already!

For what it's worth, I'm in Pennsylvania.

a2j

We got our GL320 when it was at 61k miles. No regrets so far.
I'd ask if rear shocks and all, if any, air springs were replaced. If not, you will have to do it rather sooner than later. I don't add anything to the fuel. Once in a while I fill up with B20 to lubricate the pump. Not sure if it even does anything. Leaking oil cooler seal is another thing, but its not just for GLs.

DennisG01

Thank you. I will definitely inquire about the shocks and air bags.

Good point about the cooler seals - the same engine is used in other vehicles and I can look in those forums, as well.

DennisG01

The dealer (independent) has already replaced the air bags and the cooler seals. I'm test driving the vehicle for a few days. The air suspension works well and holds it's height. There's a couple other small issues that the dealer is going to fix - the biggest of which is the rear hatch doesn't open and close automatically. The other stuff is pretty minor.

Not that I care too much about the Nav system (I'm 42 years old and have gotten along just fine so far without one), but I would like to at least figure out why it doesn't show my location. I read something in the Command manual about it having to "find itself" again. Maybe that's all it needs - a little more time to figure out where it is? I'm in PA and the map thinks it's in CA.

amthatiam

Hi Dennis,
I have an 08 GL320 that is just about to turn 150,000 miles and absolutely love it. Sounds as though you are mechanical so you should be able to save a bunch o money. My opinion is that these trucks are easy to work on as far as the maintenance and general upkeep. Common issues are the air suspension which really is just a standard maintenance issue really, I don't get why people get upset when the system has a part fail, it's really all just normal wear and tear. Though it can be inconvenient if a part fails and leaves the truck sitting in a parking lot with the bags deflated and the compressor not working, or a bag fails wile driving.

I replaced the rear air bags on mine recently, very simple and looked into the fronts, Arnott has a really good video to swap them, not very difficult, I bought a set of front bags and have them as spares in my shop in case one fails I'll replace the pair.

Other common areas to watch for are the rear hatch latch which you mentioned, the oil seals which you mentioned and apparently being remedied, also the transmission has an electronic gadget called a conductor plate which is known to fail, do a search and you will find much information about it, their are a couple of companies that will swap out/exchange the plate with a rebuilt one if you pull the old and give them the part/serial number, they can even code it so you do not have to go to the dealer to have it done, sometimes the valve body fails though that is less common.

Rock auto and autohauz are your friends when it comes to parts, and I also highly recommend Akebono brake pads, great stopping power no dust, oh and also Toyo Versado CUV tires, love them very quiet and so far a little over 20,000 miles and well more than half the tread left.

I've gotten as high as 27.8 mpg highway and average 22-23 around town. I really like this truck.

Dan

DennisG01

Dan, thank you - that is some great information to hear! I had not heard of the (possible) tranny problem before. I will do some searching on that.

Just out of curiosity, is that mileage according to the computer or hand calculated? The reason I ask is my older BMW 528's computer tends to run about 1 to 1.5MPG on the 'high' side compared to hand calculating. Not that one or two MPG really matters, I'm just curious. Also - what speeds do you typically drive on the highway?

Thanks again!

a2j

replacing airbags and struts after 60k miles is premature failure and not a regular wear and tear in my book. But than again, I'm used to japanese vehicles, so maybe I'm expecting too much from something that was made in alabama.

amthatiam

I always hand calculate the fuel mileage as I don't trust the on board system, if I keep it at 65-70 on the highway it does really well. I drove from Lexington Kentucky to Souderton PA. one tank 737 miles 26.5 gals to fill, I fill it to the top of the filler neck every time.

Bimmer777

My normal highway driving speeds of 75-80mph I get 21-22mpg. However, I took a 500 mile trip to Canada back in November and was driving behind a boxtruck with racecar on trailer, so speeds were about 60-65mph. The GL had 6 people in it and loaded. Got 28mpg on that trip! So speed matters a lot.

DennisG01

That's interesting to see such a difference at the different speeds; although at 80mph, that still ain't too bad! I have a '98 3/4 ton Suburban with a diesel and I see a difference with speeds, too. Aside from the noise that the Sub will make at 80mph, I'd be down to about 16/17mpg. Although given it's rather UNaerodynamic shape, it's 7,000lb+ weight, and the older/inefficient style fuel injection, I suppose that isn't too bad, either. 'Course, it doesn't ride "quite" as nice as the Merc, though...

DennisG01

As sometimes is the case, it took a little longer to put everything together and get the deal done. But all in all, it came together nicely for what I believe to be a very fair price, too. It still has the light oil leak, but we'll work through that. They tore into the cooler seals repair they did to see if they made a mistake there, but everything was dry. They added dye to the oil to try and track down where it's coming from with no luck. They are absolutely "good for it", meaning as soon as they/me/someone else finds the leak they will repair it. For now, I took delivery and will monitor things. The business has been around for about 30 years and has very good reputation in the area with lots of repeat customers.

If there's any ideas as to where the leak might be coming from (common spots?), all thoughts are appreciated. The leak shows up dripping out of the flywheel housing. I'm kinda thinking rear main seal?