Mercedes-Benz GLA Forum banner
1 - 4 of 4 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter · #1 ·
Hi-I've had a lot of foreign cars so I am not new to the cost madness associated with them but I recently downsized to this MB. I bought this car used 8 months ago as the second owner with 35k miles on it from a dealer who has sold my family many MBs. Bought the extended everything warranty: rims, paint dents etc and today took it in for schedule A service and for this clunking that I have heard from day one but it has gotten worse.
Here is what came back:
$393 spark plug-???
Replace, mount and balance ONE tire-$360
Rear axle fluid change -$660 (this is their recommendation but also the only way to figure out the differential issue so if I don't do it, I'll never know what the issue is)

I have read a lot of threads about people having to have the rear differential being replaced sometimes 4-5 times on this model. I also cannot help but think that has affected the balance of the tires hence the hefty fee for that above. Can anyone shed some light as to the spark plug replacement and more specifically the rear differential issue being chronic or widely known as an issue?
Thanks-
I am in the Chicago suburbs
 

·
Registered
2018 Gla250/4matic mountain grey option 1 and more
Joined
·
16 Posts
Hi-I've had a lot of foreign cars so I am not new to the cost madness associated with them but I recently downsized to this MB. I bought this car used 8 months ago as the second owner with 35k miles on it from a dealer who has sold my family many MBs. Bought the extended everything warranty: rims, paint dents etc and today took it in for schedule A service and for this clunking that I have heard from day one but it has gotten worse.
Here is what came back:
$393 spark plug-???
Replace, mount and balance ONE tire-$360
Rear axle fluid change -$660 (this is their recommendation but also the only way to figure out the differential issue so if I don't do it, I'll never know what the issue is)

I have read a lot of threads about people having to have the rear differential being replaced sometimes 4-5 times on this model. I also cannot help but think that has affected the balance of the tires hence the hefty fee for that above. Can anyone shed some light as to the spark plug replacement and more specifically the rear differential issue being chronic or widely known as an issue?
Thanks-
I am in the Chicago suburbs
I also have an 18 4matic I have 37k on it. I can tell you from experience that all your tires must be from the same manufacturer same style and must be within 3/32nds of each other if not they will cause drive line vibrations and damage to the rear diff As the tires will rotate at different speeds causing the diff to overheat. I recently replaced all of my tires so as to maintain a rotational rpm balance among the four tires. 4 magic is a fantastic system but there are some drawbacks.
 

·
Registered
Joined
·
285 Posts
I've done the rear diff service (oil) twice now with not quite 31k on the car, that is way too much to pay. Both times mine was about $250-270 each time and even that I consider expensive. I would guess they changed all your spark plugs, again that seems expensive but I've really not looked at how difficult they are to get to. I will be doing mine soon as well, I think the plugs are something like 40k service.
 
  • Like
Reactions: Huey52

·
Super Moderator
Joined
·
952 Posts
Yes, GLA45 spark plug replacement interval is at 40K miles. GLA250 even longer at 50K miles.

Since spark plugs these days last so long there may be a bit less logistical design emphasis and therefore their remove/replace effort may be more intensive and therefore cost more (haven't done mine so just conjecture). Benz et al luxury marques these days love to shroud everything in plastic panels as well. And of course the rear 'plugs on any traverse mounted engine are innately more difficult. Even my home Generator's V-twin rear 'plug had to be done essentially in the blind, taking me more care-time.
Rectangle Font Parallel Pattern Circle

Rectangle Slope Font Material property Parallel

I've done the rear diff service (oil) twice now with not quite 31k on the car, that is way too much to pay. Both times mine was about $250-270 each time and even that I consider expensive. I would guess they changed all your spark plugs, again that seems expensive but I've really not looked at how difficult they are to get to. I will be doing mine soon as well, I think the plugs are something like 40k service.
 
1 - 4 of 4 Posts
Top