Bimmer777

I am looking to buy a used GL diesel mostly for my parents use but at times for me and towing as well. I am wondering about the technical and practical differences between the two different motors (from the 320 and 350), and more importantly the reliability of each. I will look to buy a truck with around 100k miles and hope to put on another 100k miles on it, which should be cake for a diesel motor. Not looking into extended warranties obviously, but have access to a shop and would do most work there. Labor would be free, but would have to pay for parts.

What are technical specs for each engine? Is one known to be more reliable than the other?

What is general reliability of GLs? I have been under the impression that the GLs are pretty reliable, unlike ML counterparts. I'd love to know what can go wrong on them and the cost as the miles go up.

What should I expect in terms of maintenance? Again, I realize diesels are more expensive to maintain but dont really know whats involved.

Any help or advice is greatly appreciated!

N_Jay

07 and 08 are CDI (no urea and have a spare)
09 and up are Bluetech and have urea and no spare.
11 and up are supposed to have the new oil-cooler seal and be less prone to leaks.
All seem to be susceptible to aging sensors and such triggering random limp mode issues.
Not a problem, but can be annoying.
In general newer has more bells and whistles and better NAV etc. but not everything changes every year.

KrustyKustom

I have a mid year 2011 ( build nov 2010). Something else I learned at my 40k maintenance was the 7gtronic uses the new low friction 134fe fluid that is blue, noted as low friction. Unclear if the tranny is a. 7gtronic +, but it does use the + type fluid.

The blue fluid is not backwards compatible.

Bimmer777

Thanks for the info. I am leaning towards the early model 320CDIs with higher miles. I dont mind a sensor here and there going bad. Its annoying but still easy enough fix. I am more worried for higher ticket items. How is the air suspension? Do the turbos hold up on these?

N_Jay

I have not seen many people talk about bad turboes.


The sensor problem is a pain because you are always guessing at why it is limp.
No check engine, rarely a stored code and comes out of it with a restart.
Lots have suspected EGR issues, or sticky intake flaps.
The latest suspect is a very inexpensive DPF pressure sensor.
Some say cold weather causes it, I am leaning towards wet weather on mine.


Air suspension seems like all the rest, somewhere between 50 and 100K miles or 3 and 7 years you need a set of air springs.
Most like replacing with Arnott.


Read up on the oil cooler.

Bimmer777

N_Jay - very helpful.

I didnt understand what you meant about sensors originally. Thought it was either O2 or NoX sensors and problem solved. So these are unknown bugs that creep up every now and then. But you say it resets with a restart and goes away for a while? I'll read up on it more.

Looks like i should budget in a grand to replace the suspension with Arnott since I am going for higher miles truck. No big deal, but good to know parts are about $1k.

Will read up on oil cooler. I would think there would be a fix for it of some kind since its such a known problem.

Two more questions off the top of my head - any electrical issues like navigation or radio that would need dealer fix or programming? And separately, how are these things with towing? I am guessing should be pretty good since its a torquey diesel.

N_Jay

Depending on how it was maintained the shock may have been done before you buy it.


At least one of my fronts was replaced with MB (not Arnott).
I need to pull the VMI to find out for sure.


The "fix" for the oil cooler is to replace the seal with the later part.
It is an "easy" job with a total of 12 to 15 hours of difficult disassembly and reassembly surrounding the easy part.

Command and NAV are like any other MB of the era; solid, behind the times and expensive to fix if they break.


As for towing, That is what they do best. The air suspension combined with the torque engine, the overall weight and the long wheelbase make for one EXCELENT family friendly Tow SUV.

Bimmer777

Ah, makes sense that the oil cooler would be in a stupid location. But hopefully one time fix with upgraded part and would be done.

I am not familiar with MB Command and NAV so didnt know. I have history with BMWs and Volvos, and more recently Evos (I know, way different). I guess its the risk I have to take with the electronics.

Bimmer777

Also, is there a reference where I can look up the options that were available on early model GLs? I guess there were Package 1 and 2, but i dont know what was included in each. Is there a vin decoder that can tell me what a particular car has?

Sorry for all the questions.

N_Jay

You can sign up for MB StarTec EPC and decode vins.


I found a few option lists on line, I will try to send them, but today is not a good computer day. (Lightening strike last night)

Fourdiesel

Best way to find out about the COMAND and Nav is to test drive one of the same year you are thinking about buying. Compared to ANYTHING else you will NOT be pleasantly surprised at these two items. Example - we were driving through California on our way to San Diego and while in Stockton wanted to go to a Walmart. Did a search for Walmart and the COMAND told us the nearest one was in St Louis, Mo! Haven't trusted it since.

Bimmer777

Not that concerned about how fancy it is. Just want it functional and dont want to spend an arm and leg to fix it. I use Google Maps for any kind of navigation anyway. The absolute best in my opinion.

sak335

Bimmer777, I'm a BMW guy myself (over 20 years) and bought my 2012 GL350 specifically to tow my race car (1994 BMW 325) in a 24' enclosed trailer (6500 lb, loaded.) I used to tow with a Chevy and everything about the Benz is better.

Essentially you trade Siemens controls in the BMW for Bosch in the Mercedes, and of course Mercedes uses different connectors so you have to learn how to unclip them without breaking them. I've only done minor services so far but I've poked around a bit and haven't found anything too bad. The one thing that seems clear is that (and no offense to this list) there is a lot more information out there for fixing BMW's than there is for Mercedes.

A few things about COMAND are quirky and you need to read the manual to figure out quite a few things, but once you figure them out they are OK. Mine has NAV and I use it for getting from A to B, but I use my phone if I need to find something like fuel or a restaurant rather than trying to use the vehicle to do it.

N_Jay

Same with Porsches and Hondas!


Seems the MB mystique has a down side for good information flow.

Bimmer777

Ha thats great to hear. I used to have an e46 M3 for a while, hence the user name. Just stuck with it across forums even though I don't own it anymore. But I plan to use the GL for towing a racecar too, but mine is an Evo 9 Rally Car.

And yes, agreed on scarcity of information on Benz forums. Usually you'd find more technical info.

N_Jay

Us second owners of higher mileage diesel 164's will have to stick together and share info.

Bimmer777

Yes, and I plan to keep mine for a while. Even though parents will use it most of the time, I am the one who is stuck with the repairs