S_W222

Does anyone have any real experience between the 580 and 450? Any pluses and minuses beside engine power, smoothness, etc. Am specifically interested in reliability and engine performance in general as a family hauler.

Additional context: Again, my BMW dealer is offering me same amount we paid for our X7 in exchange to some issues they've been trying to fix since we got it brand new not long time ago this year (their way to avoid buyback, which I appreciate). They have many X7s (none of them is as good as ours) but they also have 3 good and well equipped GLS (2x 450 and one 580). I am tempted, but still not sure. X7 issues will be fixed soon for sure but can take sometime, and I don't mind the GLS but still LOVE the X7. If I decide to trade for a GLS, am interested to hear about the 450 vs 580 outside the typical engine power discussion.

jkaetz

Your statement contradicts itself. You ask if there are differences besides the engine, then you ask about reliability and engine performance.

The 450 isn't slow, but the 580 moves effortlessly. The M176/177/178 engine has been in use for years in various vehicles. I don't believe there are any major known issues.
Outside the engine, the 580 lets you add E-ABC and includes some optional things on the 450 as standard.

wildta

If the 580 has E-ABC, I'd get that. I have a GLE 580 with E-ABC and 22" wheels and at the moment I'm renting a GLS 450 with airmatic and 21" wheels. The I6 is adequate even with 7 people going up very steep grades, sure you can hear the engine straining under those extreme circumstances but it's a lot better with the MPGs than the V8. I'll say that I easily got used to the I6 after a 100km of driving, and I can't believe I'm saying this but I probably wouldn't even miss the V8, afterall it's a family hauler and not a sports car.

What I miss about my GLE is the E-ABC. I don't feel any connection to the road with the Airmatic, sport mode is hardly discernable from comfort mode. I don't feel as confident taking curvy roads as fast as I do in my GLE since the E-ABC also acts as sway bars keeping the vehicle flat in turns. I have also learned that the electric 2nd row seats are really slow to move out of the way for the 3rd row passengers to enter/exit. My only comparison would be Escalades and Suburbans rentals, I much prefer the manual 2nd row folding operation in those vehicles to make it faster.

wildta

I didn't know this but I read that the GLS (including the GL) has always been designed for more comfort than the GLE (and ML) so maybe my comment here is a bit of an apples to oranges comparison.

jkaetz

Our E-ABC GLS feels very connected to the road. It's actually deceptive and can get you into trouble since it won't feel like your on the edge until the tires break free.

OldManAndHisCar

We got the 8 as the 6 did NOT qualify for the Fed Tax (company car) deal....due to weight. That said, it has been a blessing to have power on tap, ZERO issues with the engine, certainly as compared to the M157 in my E63. The Designo interior is amazing....(I think you can get that on the six). On the rate times we have needed a "truck" (towing)...it is a god send. Now we have a Sprinter 3500 (dualie) that we use to tow the occasional trailer - did so just yesterday picking up a new medical bed.

chassis

M17x 4.0TTV8 is becoming more frequently known for rear main seal failures as a result of failed oil-vapor separators. Most commonly in E63 installations but also reported elsewhere. A few recent incidents reported on mbworld. Oil-vapor separator design is borderline and seems sensitive to tube/pipe geometry of each vehicle installation. It is more or less a distillation system and sludge builds in the still (OVS) and internal valves, depending on vapor temperature and flow velocity which is vehicle installation dependent.

Read this site.

Do not own any MB without manufacturer’s warranty.

Caveat emptor in extremis.

wildta

Have you read or heard of any examples of the RMS on the GLE or GLS? I haven't yet. 🤞🏽

chassis

No.

A question for you: have you read all of the RMS failure posts on this site?

wildta

Not all the posts since that RMS thread is quite long but I started following it maybe a year ago. Hence the crossing of fingers, I'm hoping that the RMS issue isn't contagious across all the models, and so far it doesn't seem to be but maybe I missed something that you might be aware of?

mikapen

The only engine that I know of where this was common, is the Cummins inline 6 in the years just prior to their adopting DEF.

Even in that case it's not enough to reduce its desirability.

DC-BENZ

I thought the tires would unexpectedly break free in curve mode but I got a progressive understeer the one time I went 9/10ths in a corner.

Splaktar

If you love the x7, I don't think that you will like the 450. The 580 (with E-ABC) is much more connected to the road and enjoyable to drive if you want a feeling like the x7. It is not on the same level of driving feel as the x7 though.

The 580 (with E-ABC) does give a superior and smoother ride for its passengers than the x7.

Does the dealer's 580 have any other options like executive rear seats or captain's chairs? Acoustic glass? Off-road package? AMG line?

wildta

To be eligible for the Section 179 deduction, a vehicle must have a GVWR (gross vehicle weight rating) over 6,000 pounds, but not more than 14,000 pounds. The GLS 450 qualifies for Section 179. It weighs 7275lbs GVWR.

It doesn't really matter since you already have your V8 but I thought others should be aware.