2011 E550 Transmission Slipped going 80mph
I was driving my 2011 E550 4m on the highway at roughly 80mph, as I started going uphill the transmission starting slipping and revs climbing and I could not maintain speed. I got off the next exit about a mile down the road, I came to a complete stop and when i tried to pull away from the light the car would barely move. I was able to pull into a parking lot, i went to position the car after pulling in and didn't have reverse. I shut the car down waiting for the tow truck, when he arrived I started it back up and did have reverse. (i have a suspicion the car would have driven)
I had it taken to a local shop (only one who could take a look midday Friday). He is reporting no leaks of any kind (although it looked like it was leaking underneath where the car was parked, hard to tell with rain) and has taken the car on 2 drives of 15+ miles and has not been able to repeat the issue. He let the car idle for 25 minutes between rides, there are no codes coming up when checked.
Car has 130,000 miles, fluid was changed about 25,000 miles ago. The car is driven 50-75 miles daily with no previous issues.
Any thoughts would be appreciated, thank you.
matt
Could a bad battery cause this issue? Was just thinking that I haven't changed it since i bought the car 8+ years ago, the aux has been replaced but not the primary.
matt




I was driving my 2011 E550 4m on the highway at roughly 80mph, as I started going uphill the transmission starting slipping and revs climbing and I could not maintain speed. I got off the next exit about a mile down the road, I came to a complete stop and when i tried to pull away from the light the car would barely move. I was able to pull into a parking lot, i went to position the car after pulling in and didn't have reverse. I shut the car down waiting for the tow truck, when he arrived I started it back up and did have reverse. (i have a suspicion the car would have driven)
I had it taken to a local shop (only one who could take a look midday Friday). He is reporting no leaks of any kind (although it looked like it was leaking underneath where the car was parked, hard to tell with rain) and has taken the car on 2 drives of 15+ miles and has not been able to repeat the issue. He let the car idle for 25 minutes between rides, there are no codes coming up when checked.
Car has 130,000 miles, fluid was changed about 25,000 miles ago. The car is driven 50-75 miles daily with no previous issues.
Any thoughts would be appreciated, thank you.
matt
This means you would have a slow leak that took level down during the 25 000 miles you drove it since the fluid change.
I don't think the fluid can drain too low thru the transmission pan gasket so the leak would need to be somewhere else, like at the transmission cooler leaking out or into the engine cooling system.
Just guessing here...
matt
Just reread your comment, " into the cooling system" . Had that drained at the same time I had the transmission serviced last and it was "clean" for coolant anyways.
Last edited by MRLE550; Apr 23, 2024 at 02:43 PM. Reason: addition




matt
Just reread your comment, " into the cooling system" . Had that drained at the same time I had the transmission serviced last and it was "clean" for coolant anyways.
Are you the first owner? How well has that thing been serviced? The NIGHTMARE scenario is that you have intermix between your radiator/transmission cooler at the radiator with coolant, can you check your coolant to make sure its not oily? Coolant has something in it that strips the glue from the friction discs which can total out your transmission. I've yet to see this happen but its possible with any car with this radiator.
I sell transmission services damn near almost annually and nothing fixes a car like maintenance. Having a W212 E550 myself I have a soft spot for you and I want to make sure I help you as much as I can getting through this.
Vaico has the best filter kit I use.
Filter Kit
If you wanna upgrade to 100% synthetic fluid, use preferred customer program to save 25%. This stuff ages and handles heat cycles much better, with better cold flow characteristics on those early morning drives.
https://www.amsoil.com/p/amsoil-sign...tf/?zo=7236674
If you have the patience to DIY this I can walk you through it over the phone, call me.
Alpha European Autotech
Purchase Amsoil at 25% off from me
Chris Tran, Retired Alpha European Autotech Owner
Amsoil Independent Dealer #7236674
Are you the first owner? How well has that thing been serviced? The NIGHTMARE scenario is that you have intermix between your radiator/transmission cooler at the radiator with coolant, can you check your coolant to make sure its not oily? Coolant has something in it that strips the glue from the friction discs which can total out your transmission. I've yet to see this happen but its possible with any car with this radiator.
I sell transmission services damn near almost annually and nothing fixes a car like maintenance. Having a W212 E550 myself I have a soft spot for you and I want to make sure I help you as much as I can getting through this.
Vaico has the best filter kit I use.
Filter Kit
If you wanna upgrade to 100% synthetic fluid, use preferred customer program to save 25%. This stuff ages and handles heat cycles much better, with better cold flow characteristics on those early morning drives.
https://www.amsoil.com/p/amsoil-sign...tf/?zo=7236674
If you have the patience to DIY this I can walk you through it over the phone, call me.
Thank you Arrie and Chris.
I am the second owner, I've had the car about 8 years for 100 of the 130k miles. I do most of the maintenance myself aside from the transmission service or when I just flat out don't have time. I live in PA so corrosion is an enemy here garage kept or not. I won't get into the whole story but a lightbulb went off yesterday when reading a post, makes me think i could have had an external leak near the transmission cooler(perhaps a seal/gasket/line). I've never really looked under the very front under panel, I'm going to pull that and take a look today along with seeing if anything is in the coolant.
matt
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Otherwise, I'm going to throw a new battery in for my own sanity since it at least 8 years old. Next I'll schedule a transmission service and go from there. I just wish there was an easy way to check the fluid level.(Also for my sanity)
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Otherwise, I'm going to throw a new battery in for my own sanity since it at least 8 years old. Next I'll schedule a transmission service and go from there. I just wish there was an easy way to check the fluid level.(Also for my sanity)
It is a job to do but at least it would tell if the fluid is at correct level. Maybe your indy did not fill it correctly when last serviced?
It just kind of points to the low level when slipping happens going up a hill but then it is fine later on flat. Perhaps you could drive the front wheels on a ramp and see if it repeats it?
Thats my anecdoctal evidence, obviously it could be something else but I reckon the fluid is real real dark I have pics of 20-30k fluid within the 60k interval that is cooked and smells absolutely vile.
Alpha European Autotech
Purchase Amsoil at 25% off from me
Chris Tran, Retired Alpha European Autotech Owner
Amsoil Independent Dealer #7236674
Alpha European Autotech
Purchase Amsoil at 25% off from me
Chris Tran, Retired Alpha European Autotech Owner
Amsoil Independent Dealer #7236674








