GLS Class (X166) Produced from 2016 to 2019

Holy (Liqui) Moly!

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Old Jun 12, 2021 | 01:01 AM
  #1  
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AUDI Q7
Holy (Liqui) Moly!

Hello Gents,

Just hitting 40k, so time for an oilchange. Here's the ceremony:

Added 2 Proflush Engine cleaner , ran iddle for about 5 minutes.

Drained oil, replaced.with Liqui Moly LeichtLauf 5W40 (Mercedes approved, LM recommended).

Added MoS2 Anti Friction Engine treatment (2 cans).

Added Pro Line Fuel System Clener to gastank. Very powerful, it actually works, sensibly!

Will add DI Jectron Fuel Injector Cleaner before refuel.

Runs amazingly smooth and powerful! Engine shines (inside/out), literally.
Best i felt from this platform so far! BTW, it really shows its worth when pushed in triple digits pulls!! Generous powerband carrying this heavy rig fully loaded (crew&gear) with ease.

...which brings me to my next point: tune...

This LM oil would be good for tuned engines also, per LM, used successfully by one of their r a cing teams.

So very excited for the next 6k miles .

chirboiz

Bob

Last edited by Promo Bob; Jun 12, 2021 at 01:22 AM.
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Old Jun 12, 2021 | 02:10 PM
  #2  
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GLS350d V6 AMG Line G-Tronic
VIP Treatment !! Enjoy
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Old Jun 12, 2021 | 03:54 PM
  #3  
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Yesssir! Is that good. It sensibly improved everything, in Audi as well. Nothing too expensive either, outsourced from Amazon, except for DI Jectron(hard to find). Worth every DM!!!
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Old Jun 17, 2021 | 04:54 PM
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AUDI Q7
Originally Posted by Golfather
VIP Treatment !! Enjoy
not really, i just like to take care of things that take care of me. She really deserves it.
on the long road now, long roadrips in triple digit temps, rig sails beautifully, fully loaded, ac blast, love the generous powerband! Lots of torquies early on, wonderful pulls especially in the triple digits!!!
MPG great too(considering)..

Chirboiz,

Bob
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Old Jun 18, 2021 | 05:09 PM
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AUDI Q7

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Old Jun 19, 2021 | 09:45 PM
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2017 GLS 550
Is this 350, 450, or 550?
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Old Jun 19, 2021 | 10:46 PM
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AUDI Q7
Originally Posted by DBMC
Is this 350, 450, or 550?
550
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Old Jun 22, 2021 | 11:55 AM
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2017 GLS 550
I had JUST done an oil change and used Liqui Moly, then noticed when I was under there that there was an oil leak. I took it to the dealership and they had to remove and re-seal the lower oil pan which means they dumped out the LM and put in whatever stuff they use at the dealership I asked a few times if they could re-use the oil and they said no. I was NOT happy.
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Old Jun 25, 2021 | 04:37 PM
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Sorry to hear that, spoiled all that goodness. The secret is in the LM oil and additives together. Dealers stay away from any other than yhey sell, especially performance enhancing products. Had to tip my local oil (chain)change guy to do it right.
Anyways, runs like a charm. On the road for some 3k miles, hot weather. Excited about the next oil change when we get back.
i may switch to Molygen though if i decide to tune soon.Molygen is recommended for tuned vehicles. Have it in 2 tuned Audis and is amazing also!


Chirboiz,

Bob
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Old Jul 2, 2021 | 01:12 PM
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Too many german broads
Thinking about using the same (liqui moly engine flush), any risk using first time on a high mileage engine??
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Old Jul 2, 2021 | 02:12 PM
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Risks??? It is well known it brings older high mileage noisy engines back to smoothness.
28MPG in 100F№ weather.
Danke Schön, LM!
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Old Jul 10, 2021 | 11:44 PM
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Drop it like it's hot!
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Old Jul 13, 2021 | 07:02 PM
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GLS 450
I am impressed that your auto-start turned off your engine with that outside temp!
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Old Jul 13, 2021 | 11:17 PM
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Originally Posted by wyatt88
I am impressed that your auto-start turned off your engine with that outside temp!
yeah, 100°F @ 8pm , cooler than the 115°F during the day. Heatdome or something. Nonetheless rig performed admirably, loaded to MAX, AC full blast constantly. Merc , No Sweat!
Sweet!
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Old Mar 24, 2023 | 09:51 PM
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gl450
Just did this full service for my 2015 GL550, my car literally flashed “thank you stud” on the HUD when I reset the service indicator
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Old Mar 25, 2023 | 12:46 AM
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X166 gls450 2017
I've tried everything 229.5 and believe it or not Motul exceeds LM ... she purrs like a kitten, best stuff on the market hands down
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Old Jun 30, 2023 | 11:34 PM
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Originally Posted by 007_e350
I've tried everything 229.5 and believe it or not Motul exceeds LM ... she purrs like a kitten, best stuff on the market hands down
Which Motul did you use? The 8100 x-cess gen2?
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Old Sep 6, 2023 | 04:32 PM
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2018 GLS 550
Hmmm, based on other merc forums opinions, this should not be done. I’m interested to see how it works out for you.
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Old Sep 6, 2023 | 04:36 PM
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Originally Posted by bakestein1
Hmmm, based on other merc forums opinions, this should not be done. I’m interested to see how it works out for you.
Can I ask what you're referring to?
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Old Sep 7, 2023 | 12:28 AM
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2018 GLS 550
Some folks over at another MB forum think that the MoS2 will damage the car.
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Old Sep 10, 2023 | 10:10 PM
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So, will it, or has it?
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Old Sep 28, 2023 | 11:55 PM
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AUDI Q7
Hello Gents,
Did a beautiful 70,000 miles Liqui Moly ritual, Proflush/Ceratec&LeichtLauf, rig rides soo smooth and beautiful!
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Old Sep 2, 2025 | 09:49 AM
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W124 300D
Couple years later... I assume all still holding up well? In the market for an X166 and debating GLS 450 vs 550 for my wife's daily + family ride. Was leaning towards the 450 but your mileage is making me think a 550 wouldn't be a bad idea.
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Old Sep 2, 2025 | 10:15 AM
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Originally Posted by capflya
Couple years later... I assume all still holding up well? In the market for an X166 and debating GLS 450 vs 550 for my wife's daily + family ride. Was leaning towards the 450 but your mileage is making me think a 550 wouldn't be a bad idea.

Hello Gents,
Oldies , but goldies indeed,. Almost hitting 100k on the ig, awesome big , beautiful ride (no pun intended). After ECU/TCU tunes, air intakes, smoother, more powerful (700++ torquies), and yes better MPG, especially after intakes. It seems to stabilize better, especially around town. Have been doing the Liqui Moly ritual eversince: Proflush/ Leichtlauf 10w40/ Ceratec/MoS2 every 5k. Now for the 100th anniversary, will switch to Liqui Moly Molygen 10w40 (Also MB spec)+MoS2. Successfully used in the other 4 rings rig.

stock i think 450/550 doesn't make much difference, both thirsty, especially city driving.

is after showing it some extra love when it does wonders for you.

Cheers,

Bob

PS: So I'm getting around 25MPG highway driving, A/C, chairs on, which drops to low 20's when driven spirited. It used to drop to 10-12 when driven aggressively, but now it stabilizes at higher numbers, even when pushed hard. Hope that helps


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