Spark Plug Replacement - How to?
Thread Starter
Newbie
Joined: Apr 2025
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2020 GLS450
Spark Plug Replacement - How to?
Hi there,
Has anyone come across a video or pictorial on how to change the spark plugs in an X167 (2020-present GLS450)? I've searched online but can only seem to find videos for the older models. I
As a fairly handy home "mechanic" I'm sure I could figure it out, but I always appreciate a solid step-by-step set of instructions with pics/video.
Thanks all!
Has anyone come across a video or pictorial on how to change the spark plugs in an X167 (2020-present GLS450)? I've searched online but can only seem to find videos for the older models. I
As a fairly handy home "mechanic" I'm sure I could figure it out, but I always appreciate a solid step-by-step set of instructions with pics/video.
Thanks all!
MBWorld Fanatic!
Joined: Oct 2019
Posts: 5,161
Likes: 1,772
From: Colorado
G550
Hi there,
Has anyone come across a video or pictorial on how to change the spark plugs in an X167 (2020-present GLS450)? I've searched online but can only seem to find videos for the older models. I
As a fairly handy home "mechanic" I'm sure I could figure it out, but I always appreciate a solid step-by-step set of instructions with pics/video.
Thanks all!
Has anyone come across a video or pictorial on how to change the spark plugs in an X167 (2020-present GLS450)? I've searched online but can only seem to find videos for the older models. I
As a fairly handy home "mechanic" I'm sure I could figure it out, but I always appreciate a solid step-by-step set of instructions with pics/video.
Thanks all!
Thread Starter
Newbie
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Posts: 4
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2020 GLS450
MBWorld God!
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I am not sure if it covers your model year though is the problem, I heard the newer MBs, they transitioned to a different system.
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Maybe you could get a copy for cheaper: https://mbworld.org/forums/s-class-w...-epc-like.html
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11 E550, 16 AMG GTS, 13 S550
It's pretty painless I do quite a few of these through the shop. It's one of the few engines I openly recommend DIY on
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It's pretty painless I do quite a few of these through the shop. It's one of the few engines I openly recommend DIY on
https://youtu.be/VZqFW1Skm-4?si=VayYw__A7NzS6wq6
https://youtu.be/VZqFW1Skm-4?si=VayYw__A7NzS6wq6
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MBWorld Fanatic!
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From: Colorado
G550
PM me and I might be able to direct you to further information.
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From: Colorado
'21 AMG53 wDPP & ARC, 19 GLC300 - Former-03 C240,2 ML BlueTecs,20 GLE450 E-ABC,15 Cayenne D,17 Macan
It's pretty painless I do quite a few of these through the shop. It's one of the few engines I openly recommend DIY on
https://youtu.be/VZqFW1Skm-4?si=VayYw__A7NzS6wq6
https://youtu.be/VZqFW1Skm-4?si=VayYw__A7NzS6wq6
It's for a V6. Do you know of one for the I6?
My shop says that the plugs last a lot longer than the 60,000 recommended replacement, but the reasons to change at 60k are the really long reach (tip to seat) that gets combustion deposits, and that the factory doesn't use anti-seize on initial assembly. So there can be troubles in removing them.
And to use anti-seize on the new plugs.
I'm at 45k, and this is a likely task for me.
On a recent pre-warranty-expiration inspection, they found the oft-mentioned deteriorated plug wiring harness and warranteed it.
Last edited by mikapen; Apr 6, 2025 at 07:26 PM.
MBWorld God!
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Thanks for the link.
It's for a V6. Do you know of one for the I6?
My shop says that the plugs last a lot longer than the 60,000 recommended replacement, but the reasons to change at 60k are the really long reach (tip to seat) that gets combustion deposits, and that the factory doesn't use anti-seize on initial assembly. So there can be troubles in removing them.
And to use anti-seize on the new plugs.
I'm at 45k, and this is a likely task for me.
On a recent pre-warranty-expiration inspection, they found the oft-mentioned deteriorated plug wiring harness and warranteed it.
It's for a V6. Do you know of one for the I6?
My shop says that the plugs last a lot longer than the 60,000 recommended replacement, but the reasons to change at 60k are the really long reach (tip to seat) that gets combustion deposits, and that the factory doesn't use anti-seize on initial assembly. So there can be troubles in removing them.
And to use anti-seize on the new plugs.
I'm at 45k, and this is a likely task for me.
On a recent pre-warranty-expiration inspection, they found the oft-mentioned deteriorated plug wiring harness and warranteed it.
MBWorld Fanatic!
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From: Colorado
'21 AMG53 wDPP & ARC, 19 GLC300 - Former-03 C240,2 ML BlueTecs,20 GLE450 E-ABC,15 Cayenne D,17 Macan
I've always been careful not to over torque the plugs, but my wrists aren't as calibrated as they once were.
Still, I don't like seeing all the combustion deposits along the threads. I guess the solution is to respect the 60k mile recommendation.
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From: Colorado
G550
The article referenced in #10 above says anti-seize is a no-no, and is not necessary as spark plugs are plated to resist corrosion and interaction with the engine block alloy. However, dielectric grease on the plug boot is a must-must.
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I've used it for decades, but you're probably right, with newer plug thread coatings.
I've always been careful not to over torque the plugs, but my wrists aren't as calibrated as they once were.
Still, I don't like seeing all the combustion deposits along the threads. I guess the solution is to respect the 60k mile recommendation.
I've always been careful not to over torque the plugs, but my wrists aren't as calibrated as they once were.
Still, I don't like seeing all the combustion deposits along the threads. I guess the solution is to respect the 60k mile recommendation.
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GLE 580
Out Of Control!!
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From: unbegrenzt
2017 GLE350 4MATIC
Hi there,
Has anyone come across a video or pictorial on how to change the spark plugs in an X167 (2020-present GLS450)? I've searched online but can only seem to find videos for the older models. I
As a fairly handy home "mechanic" I'm sure I could figure it out, but I always appreciate a solid step-by-step set of instructions with pics/video.
Thanks all!
Has anyone come across a video or pictorial on how to change the spark plugs in an X167 (2020-present GLS450)? I've searched online but can only seem to find videos for the older models. I
As a fairly handy home "mechanic" I'm sure I could figure it out, but I always appreciate a solid step-by-step set of instructions with pics/video.
Thanks all!
Coil screw torque is 8Nm or 9Nm for all German brands. It doesn't matter which torque value you use.
Spark plug torque is 23Nm for all German brands. Buy them from the dealer. They are expensive. No one cares about the price of spark plugs. Use dielectric grease in the coil boot when reinstalling coils. Never use anti seize on spark plugs, coil screws, lug screws, caliper screws, axle fill or drain plugs or axle shaft nuts. Or anything else.
MBWorld Fanatic!
Joined: Oct 2019
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From: Colorado
G550
In another forum thread, there is discussion about spark plug indexing. While controversial generally, MB insists that indexing is critical on certain of its engines that use direct injection. MB branded plugs are designed to properly index when torqued to spec, and anti-seize would likely interfere with achieving this. The reference in #10 above has a link at the bottom to a MB technical paper that discusses indexing. It's cheap insurance to pay more for MB spark plugs every 50K miles to ensure it's done correctly.
MBWorld God!
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Standard maintenance is dead easy on all German brands. Search videos for E53/450, GLE53/450, GLS450. Lean how to release the coil electrical connector without destroying it.
Coil screw torque is 8Nm or 9Nm for all German brands. It doesn't matter which torque value you use.
Spark plug torque is 23Nm for all German brands. Buy them from the dealer. They are expensive. No one cares about the price of spark plugs. Use dielectric grease in the coil boot when reinstalling coils. Never use anti seize on spark plugs, coil screws, lug screws, caliper screws, axle fill or drain plugs or axle shaft nuts. Or anything else.
Coil screw torque is 8Nm or 9Nm for all German brands. It doesn't matter which torque value you use.
Spark plug torque is 23Nm for all German brands. Buy them from the dealer. They are expensive. No one cares about the price of spark plugs. Use dielectric grease in the coil boot when reinstalling coils. Never use anti seize on spark plugs, coil screws, lug screws, caliper screws, axle fill or drain plugs or axle shaft nuts. Or anything else.
MBWorld God!
Joined: Dec 2019
Posts: 32,533
Likes: 6,354
In another forum thread, there is discussion about spark plug indexing. While controversial generally, MB insists that indexing is critical on certain of its engines that use direct injection. MB branded plugs are designed to properly index when torqued to spec, and anti-seize would likely interfere with achieving this. The reference in #10 above has a link at the bottom to a MB technical paper that discusses indexing. It's cheap insurance to pay more for MB spark plugs every 50K miles to ensure it's done correctly.
MBWorld God!
Joined: Dec 2019
Posts: 32,533
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Out Of Control!!
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From: unbegrenzt
2017 GLE350 4MATIC
Ignore anything related to spark plug indexing and follow the steps below.
Buy new OEM spark plugs from the dealer
Remove old spark plugs
Install new spark plugs, torque to 23Nm
Done
Buy new OEM spark plugs from the dealer
Remove old spark plugs
Install new spark plugs, torque to 23Nm
Done
