Picture is worth .....

pic of one valve RHS rear with electrical connector
Disconnect both sides. See previous poster instructions re white locking tab and pull white tab out first and then disconnect plug.

 

Hello,

I just bought a 2021 GLE 580 and the gas mileage is horrendous. Would other 580 owners mind sharing their experience with me? I feel like the gas mileage of my 580 isn't even in the ball park but I have no frame of reference.

Thanks for your help!

 

Need more details. Not that I have a 580, but what is "horrendous"? Do you have a heavy foot or leave it in sport mode all the time?

 

I have a 580 and by horrendous I assume you mean the same 11-13 MPG I'm getting? I mean that's to be expected to a degree, it's a 2.5+ ton SUV w/ close to 500HP. I used to have a BMW X5 M50i which got a solid 14.5mpg no matter what I did.

Is that better? Technically yes, but saving gas money is not the point on a GLE 580.

 

I have a stage 2 tune on mine, and it's actually better than it was stock, but city I think I average around 15 and highway its been at 21, but I could probably muster 23mpg long distance.

 

I average 17.8 mpg … I’m 90% in town driving; 10% highway
2021 GLE 580

 

I have a 21 580 with 18k. I get about 16 city and 21 highway mostly in comfort mode.

 

2021 GLE 580.

 

Yes, this is the same horrendous mileage I'm getting in comfort mode and I definitely don't have a lead foot. I was foolishly expecting the stated epa estimates, or at least something in the ballpark...

 

I've heard the tune makes mpgs better. What tune are you running? Are you concerned about voiding your warranty?
I was considering Renntech but was talked out of it by a local authorized Mercedes dealer's director of service. He told me if there were any drivetrain issues I'd be SOL.

 

Wow! Look at you you hypermiler! 🤪 What's your secret?

 

That’s a correct assumption….EPA. City driving can be a little unpredictable but highway at a set speed should be right on or better. People with the GLE 63 are getting better than you report.

 

I hear you on wanting to trust the EPA estimates. My personal opinion is the tests really don't simulate real world driving and are usually optimistic. Wish they'd update them.
Well on the bright side, you are getting the same MPG as me and I do have a lead foot. So speed away

 

The EPA estimates are easy to beat on the highway, in Comfort mode, at posted speed limits. If you drive aggressively in Sport or Sport+ then mileage takes a big hit. On my last 4 German cars I usually got close to averaging EPA at speeds of 85+. Passing frequently on 2 lane roads, Wind and hilly terrain will all also make a difference in results.
My last two GM trucks with a 6.2 V8 averaged better than some are posting here for the GLE 580.

 

Wish we had a 580 in Canada.

 

Thats good! I see about 13-15 city 18-20 highway. I do smash wot often.
Can finally average 18mpg city and almost 25 highway.

 

who tuned?

 

Tuned through a dealer who uses Labworx. PM me if you are interested.

 

I saw a Brabus 800 waiting for pickup at the Dealer last week.
The Service Manager thought it was a good mod. He said the Tech who worked on it was impressed with the integration, and it didn't disturb any diagnostics.

My right foot is itching, but the 53 is all I can handle at the track. Not enough tire.

 

Anyone know of any exhaust kits for the 580s? I’ve only found one but it’s like $10k lol

 

Wasn’t someone earlier in this thread talking about doing something simple to the exhaust on the 580 and changing the sound. Look through the previous comments. Maybe someone will post an update and possible sound clip of the change.
Good luck.

 

Friendly but bad recommendation, sounds mediocre , and major loss of power as well as worsened mpg

 

Makes me wonder if there should be a combined GLE580 and GLS580 sub-forum since there are many more GLS580s, and together there's a decent amount.

 

Well I disconnected both of the valves in the muffler yesterday and drove fine for me first part of the day. My wife ended up taking it out on her own and I got a call from her later that day saying the check engine light is on and its shaking (misfire) and proceeded to yell at me saying "Quit modifying the car!" Guess I didn't get as lucky as some of you.

Shame because I for sure heard a difference with them unplugged. I am starting to wonder if her leaving it in comfort mode instead of sport mode had anything to do with it. Wild that just a little exhaust valve will do that.

 

Just reading this update. Bummer... I loved the gurgle on the downshift of our GLC63...