drilled back rotors?
04-07-2013, 09:22 AM
#30
This is just a wild conjecture but I noticed that breaking power on my new GL550 doesn't feel inspiring. Per Motor Trend reviews, breaking performance is very good and I presume those launch cars had drilled rotors and probably a ringer engine 
I am curious if lack of drilled rotors in the back is contributing to lack of braking performance.
I am curious if lack of drilled rotors in the back is contributing to lack of braking performance.
04-07-2013, 10:03 AM
#31
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This is just a wild conjecture but I noticed that breaking power on my new GL550 doesn't feel inspiring. Per Motor Trend reviews, breaking performance is very good and I presume those launch cars had drilled rotors and probably a ringer engine I am curious if lack of drilled rotors in the back is contributing to lack of braking performance.
I am curious if lack of drilled rotors in the back is contributing to lack of braking performance.
04-07-2013, 10:18 AM
#32
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The purpose of drilled rotors is to reduce heat under heavy use. Drilled rotors would likely not improve braking performance in normal everyday use. MB's decision to drill the front rotors only on the GL is most likely because the front brakes do most of the heavy lifting (or braking) when it comes to slowing or stopping the vehicle. The back rotors would rarely over-heat.
So I agree with Cookstar, solid rotors, while not as sexy looking, would provide a larger surface area and therefore better braking performance.
So I agree with Cookstar, solid rotors, while not as sexy looking, would provide a larger surface area and therefore better braking performance.
04-07-2013, 01:14 PM
#34
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The "brake drying" function ensures that full braking power is available even under wet conditions. And with the "priming" function, the system reduces the brake response time.
04-07-2013, 06:10 PM
#35
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The purpose of drilled rotors is to reduce heat under heavy use. Drilled rotors would likely not improve braking performance in normal everyday use. MB's decision to drill the front rotors only on the GL is most likely because the front brakes do most of the heavy lifting (or braking) when it comes to slowing or stopping the vehicle. The back rotors would rarely over-heat.
So I agree with Cookstar, solid rotors, while not as sexy looking, would provide a larger surface area and therefore better braking performance.
So I agree with Cookstar, solid rotors, while not as sexy looking, would provide a larger surface area and therefore better braking performance.
Last edited by blittle; 04-08-2013 at 04:45 PM.
04-08-2013, 10:33 AM
#36
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it looks like MAYBE in Canada if you do not have the sport package the front disks will not be drilled either.... saw two today without the sport package with no mb logo on the caliper or drilled rotors.... again this could be a couple of vehicles or all....
04-09-2013, 10:16 PM
#40
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Nov 2012 build GL350 no holes front or rear breaks. Doesn't really concern me at all since its the mamma wagon anyway. Is interesting how they are switching things up so soon...
04-12-2013, 12:24 AM
#41
got a call from MB corporate today- she listened to the entire issue and concerns of why the difference in same model year with no mention of this anywhere..
She wasnt sure why the difference and I mentioned that its was advertised in a way where we all felt that rears should be drilled as well. (had to explain what drilled exactly means)
She will do some research on this issue and get back to me- i mentioned that since it is available on same model year and different models ( not specific to a particular model) that should we expect a change (something like, though not really, like a recall)
will let you know when i know...
She wasnt sure why the difference and I mentioned that its was advertised in a way where we all felt that rears should be drilled as well. (had to explain what drilled exactly means)
She will do some research on this issue and get back to me- i mentioned that since it is available on same model year and different models ( not specific to a particular model) that should we expect a change (something like, though not really, like a recall)
will let you know when i know...
04-12-2013, 09:11 AM
#43
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got a call from MB corporate today- she listened to the entire issue and concerns of why the difference in same model year with no mention of this anywhere..
She wasnt sure why the difference and I mentioned that its was advertised in a way where we all felt that rears should be drilled as well. (had to explain what drilled exactly means)
She will do some research on this issue and get back to me- i mentioned that since it is available on same model year and different models ( not specific to a particular model) that should we expect a change (something like, though not really, like a recall)
will let you know when i know...
She wasnt sure why the difference and I mentioned that its was advertised in a way where we all felt that rears should be drilled as well. (had to explain what drilled exactly means)
She will do some research on this issue and get back to me- i mentioned that since it is available on same model year and different models ( not specific to a particular model) that should we expect a change (something like, though not really, like a recall)
will let you know when i know...
04-12-2013, 09:57 AM
#45
04-14-2013, 09:19 PM
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I have the 21" wheel package and don't have drilled rotors. Maybe it's only part of the base wheels? Doesn't make sense, but just a thought.
04-16-2013, 09:28 PM
#48
mb corporate called yesterday-- still no idea why the difference.
I was told it should be standard with amg package which I immediately confirmed that it is not as several 550s do not have it and some without amg package have it and it has nothing to do with off road package..
they spoke to MB technical staff and were told that without VIN numbers it is impossible for them to be able to identify the difference..
so I guess the only way we'll know is to provide vin number of cars with and without rear drilled rotors to be able to find out why the difference....
I was told it should be standard with amg package which I immediately confirmed that it is not as several 550s do not have it and some without amg package have it and it has nothing to do with off road package..
they spoke to MB technical staff and were told that without VIN numbers it is impossible for them to be able to identify the difference..
so I guess the only way we'll know is to provide vin number of cars with and without rear drilled rotors to be able to find out why the difference....
