[Christi K]

I’m going to be completely honest and really need input. I’ve had my car for many years, keep pretty good maintenance, but recently became disabled and therefore no more re dealership appointments. When I first start my suv it feels as though all my brakes have locked up, and a loud grinding noise… I read somewhere maybe it’s a frozen caliper and try spraying it with a little WD-40. I know your cringing right now but I didn’t know how to get home since my car wouldn’t move out of this lock position. So I did it waited about 10 mins slowly went in reverse then slowly forward back into reverse and again into drive real slow and it helped now all tires are moving. Got home shut off car, got back in car one hour later, happened all over again???? Driving it shifts normally drives normally, just happens when I’m trying to go first thing. Any ideas would be helpful, I live quite rural in Louisiana so mechanics are hard to find that understand Mercedes

 

[Csuki]

I am sorry to hear you have this problem with your ML. Great cars but it is not just a car anymore when it stops working... Do not use WD-40 on your wheels/brakes as this is not suitable for the job and it might cause your brakes to stop working properly!

One thing I had to really create a habit for is checking the release of the emergency brake before every drive. This is mostly due to the fact that this is not a 'regular' method of applying an emergency brake in Europe. Check if it is released properly, try to apply it and then releasing it again. Something might be wrong there but it would only effect the rear wheels.

If your on of your brakes (or multiple) is stuck you should notice an increase in fuel consumption as I read you can still drive. Another thing that might happen is one of the wheels getting extremely hot when driving due to the increased friction. When I ride a lot of offroad and dirt roads mud and sand can get stuck in the caliper/piston but that would require a complete rebuild of the caliper assembly.

If you want to check your brakes you will have to jack up the car, remove the wheels and do some serious mechanical work. It includes removing the calipers and brake pads and releasing the piston (which can be dangerous because it can launch itself out of the piston). If the seal is OK you can just use the proper lubricant to get the piston to move smoothly again. If it is this bad it might require a new piston and seal.

The tricky part with the ML is working with the ABS system. In order to work on the brake system I believe you need advanced scan tools to work with the ABS system. Perhaps the ABS system is faulty in some way (valve or something) which sometimes happens if your wiper fluid reservoir starts leaking wiper fluid over the ABS module.

The information you have given is really minimal but maybe another member can help out!

Whatever the issue is I would strongly advise you to look out for a mechanic that can help you locate the issue.

Hope you can get it fixed soon, please let us know if it got fixed!

 

[khomer2]

More info please for readers.
Locked up?
Which side? or Both.
Have you checked brake fluid levels?
When was the last time they were flushed?

 

[Christi K]

I am sorry to hear you have this problem with your ML. Great cars but it is not just a car anymore when it stops working... Do not use WD-40 on your wheels/brakes as this is not suitable for the job and it might cause your brakes to stop working properly!

One thing I had to really create a habit for is checking the release of the emergency brake before every drive. This is mostly due to the fact that this is not a 'regular' method of applying an emergency brake in Europe. Check if it is released properly, try to apply it and then releasing it again. Something might be wrong there but it would only effect the rear wheels.

If your on of your brakes (or multiple) is stuck you should notice an increase in fuel consumption as I read you can still drive. Another thing that might happen is one of the wheels getting extremely hot when driving due to the increased friction. When I ride a lot of offroad and dirt roads mud and sand can get stuck in the caliper/piston but that would require a complete rebuild of the caliper assembly.

If you want to check your brakes you will have to jack up the car, remove the wheels and do some serious mechanical work. It includes removing the calipers and brake pads and releasing the piston (which can be dangerous because it can launch itself out of the piston). If the seal is OK you can just use the proper lubricant to get the piston to move smoothly again. If it is this bad it might require a new piston and seal.

The tricky part with the ML is working with the ABS system. In order to work on the brake system I believe you need advanced scan tools to work with the ABS system. Perhaps the ABS system is faulty in some way (valve or something) which sometimes happens if your wiper fluid reservoir starts leaking wiper fluid over the ABS module.

The information you have given is really minimal but maybe another member can help out!

Whatever the issue is I would strongly advise you to look out for a mechanic that can help you locate the issue.

Hope you can get it fixed soon, please let us know if it got fixed!

Thank you for all of your insight. I will keep you apprised if my findings.

 

[Christi K]

More info please for readers.
Locked up?
Which side? or Both.
Have you checked brake fluid levels?
When was the last time they were flushed?

I’m not positive which sides but I think it’s my rear brakes both sides.
Locked up meaning as I try to drive forward I feel as though my brakes are holding me back even though I’m pressing the gas petal.
Brake fluid is full
Can’t remember when flushed, trying to look up in previous servicing paperwork

 

[khomer2]

Serviced by an (qualified) indie?
When?
Did they check and service the rear brakes?
It's possible that the parking brake friction material (one side of both) came off from the shoes?

 

[Witek_M]

I’m not positive which sides but I think it’s my rear brakes both sides.
Locked up meaning as I try to drive forward I feel as though my brakes are holding me back even though I’m pressing the gas petal.
Brake fluid is full
Can’t remember when flushed, trying to look up in previous servicing paperwork

Have someone stand besides the car and listen where noise comes from. I am with @khomer2 parking brake material may have rusted off shoes.

 

[Christi K]

Serviced by an (qualified) indie? When? Did they check and service the rear brakes? It's possible that the parking brake friction material (one side of both) came off from the shoes?

Serviced by an (qualified) indie? When? Did they check and service the rear brakes? It's possible that the parking brake friction material (one side of both) came off from the shoes?

Serviced by a foreign car specialist ASE ( as good as I can find out here). Jan, last year Yes they inspected all brakes said front was fine and back brakes were installed Never thought of the parking brake, I never use it. Thank you for your feedback, greatly appreciate it. I’ve been told different things to look at: Master cylinder Replace calipers New brakes Caliper pins Transmission flush Brake fluid flush Transmission fluid Manuel valve position switch Lateral acceleration sensor These are all different feedbacks I’ve heard so far…. any thought on these?. Someone also just suggested to have someone stand outside to try and hear where the sound comes from, so my pastor is going to come over after church on Sunday to help me out.

 

[khomer2]

Dont throw parts at it until you check the parking brakes.
Also, those need to be used regularly (massaged) otherwise they will become problematic.

 

[Christi K]

Dont throw parts at it until you check the parking brakes.
Also, those need to be used regularly (massaged) otherwise they will become problematic.

Ok will check into the parking brake first thing before I do anything else. I can’t say thank you enough.

 

[Witek_M]

Ok will check into the parking brake first thing before I do anything else. I can’t say thank you enough.

Need to get all four wheels off the ground and attempt to spin them.