gi_jon31b

Hello everyone!

I am looking at buying a GL and ditching my Suburban and I'd like a diesel for the better fuel economy. I've done my research and have seen the posts about the emissions issues and needing repairs on some of the diesels. That doesn't concern me too much as it appears to be something that I can take care of myself. Having said that, what should I be looking for or aware of in my search? What are the pros/cons of the CDI compared to Bluetec? Are there any years that should absolutely be avoided or sought after and why? I haven't been able to locate a buyers guide for these models like I have with my current S class and previous Mercedes cars.

Thank you all for your help.

Max Blast

Any and all years of the Mercedes OM642 CDI and BlueTec should be avoided at all costs.

the CDI doesn’t have DEF injection which is simpler but also more prone to EGR funky g up the manifolds and triggering random limp home events.
the BlueTec has DEF and a less intrusive EGR but is still a complex system with many opportunities to go into limp home mode at the first sign of a fault.
Both have leaky oil seals that if not rectified will grenade the engine in short order. And the mileage savings is not enough to offset the increased maintenance cost.

for less upfront and less maintenance money you can get a GL450/550. Gas mileage in a GL550 or 450 can get up to 18-19 on the highway, so the difference in that and your GM product is negligible.

stick with your burb or look for a GL450/550.

do not get a MB diesel.

gi_jon31b

My Suburban gets 12 mpg if it's lucky and I've seen the MB diesels get around 30 combined. I can do the maintenance which is a significant savings and am aware of the oil gasket issues and limp mode problems. I would be bypassing and deleting all of that anyhow. The fuel savings is what I'm looking for mostly.

Max Blast

You’ll be slightly ahead of average joe by DIYing, but chasing Fuel savings alone would not be enough in my book to consider changing cars; it’s also not my experience. The gl diesel will get around 23; 30 if you’re drafting a semi on the highway. That’s the best I ever saw with my 320 CDI and you don’t want to be drafting semis.

my 05 burb gets 14.5 no matter what, and my 07 GL450s both get around 17. Maybe 19 if you’re cruising. Considering the cost of selling and acquiring a vehicle, and the higher cost of entry and parts you will have to throw at an x164 diesel there are no net savings.

but if you’re going to delete all the crap my recommendation would be the CDI, seems to be less complex than having to program out AdBlue. Also these have fully depreciated so cost of entry is lowest.