Excessive Engine Braking in 2nd, 3rd, and 4th Gear/ HELP

[QawimK]

Vehicle Information:
• Model: 2011 BMW 328i xDrive
• Transmission: GM Transmission
• Current Mileage: [123,000]

Problem Description:
I’ve been experiencing an issue where the car feels like it’s engine braking excessively when letting off the gas, mainly in 2nd, 3rd, and 4th gear. It happens more when the car is warmed up. There are no rough shifts or hesitation when accelerating; the issue is only noticeable during deceleration. The engine braking feels more pronounced than normal, and it almost feels like the car is downshifting unnecessarily also the exhaust cuts off like it does when shifting.

Recent Maintenance:
• Transmission Fluid: Recently changed.
• No rough shifting or hesitation during acceleration.
• No fault codes: I’ve scanned the car, and there are no active transmission and only a code for the front right wheel speed sensor

Potential Cause:
I suspect this might be related to a faulty front right wheel speed sensor. I’ve heard that the speed sensor could be affecting the transmission’s ability to properly handle engine braking.
I’ve also considered the possibility of the torque converter lockup not disengaging properly or the transmission needing an adaptation reset but not sure.

What I’ve Already Tried:
• Transmission fluid change (no improvement).
• Scanned for fault codes (none found).
• Took it to two different shops. They didn't find anything wrong and told me its normal.

Request for Help:
Has anyone experienced something similar? Could a faulty wheel speed sensor be causing this issue? I’d appreciate any advice on troubleshooting or fixing this problem.

Additional Information:
• The issue seems to occur mostly when the car is warm.
• I haven’t noticed any problems with rough shifts or hesitation during acceleration.

[drewusmaximus]

It could be the wheel sensor, since you have the xi model, but what kind of fluid did you use? Valvoline Multi vehicle full synthetic (Red bottle)? That's what I used on my 2011 328xi and the transmission loves it. Did you change the filter? Did you reset the transmission by turning the car in the on position and holding down the gas pedal for one minute, then turn off the car and wait two minutes, then start the car? Do you have ISTA to reset the adaptations?

[QawimK]

It could be the wheel sensor, since you have the xi model, but what kind of fluid did you use? Valvoline Multi vehicle full synthetic (Red bottle)? That's what I used on my 2011 328xi and the transmission loves it. Did you change the filter? Did you reset the transmission by turning the car in the on position and holding down the gas pedal for one minute, then turn off the car and wait two minutes, then start the car? Do you have ISTA to reset the adaptations?

I did use that fluid for the trans and it works great. I just changed the fluid not the filter. Should I? I took it to a shop expecting them to do the filter but they just did the fluid change saying you’re not supposed to change the filter. I haven’t reset the trans yet or have a ISTA. I’m planning too after i do my speed sensor to see if that fixes it.


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[QawimK]

It could be the wheel sensor, since you have the xi model, but what kind of fluid did you use? Valvoline Multi vehicle full synthetic (Red bottle)? That's what I used on my 2011 328xi and the transmission loves it. Did you change the filter? Did you reset the transmission by turning the car in the on position and holding down the gas pedal for one minute, then turn off the car and wait two minutes, then start the car? Do you have ISTA to reset the adaptations?

I did use that fluid for the trans but I didn't change the filter. Did you change the filter on yours? Ill reset the transmission tomorrow and see if the problem still exist. I do not have a ISTA to reset the adaptations, and not sure how to get one exactly.

[JDStrickland]

Vehicle Information:
• Model: 2011 BMW 328i xDrive
• Transmission: GM Transmission
• Current Mileage: [123,000]
Recent Maintenance:
• Transmission Fluid: Recently changed.
• No rough shifting or hesitation during acceleration.
• No fault codes: I’ve scanned the car, and there are no active transmission and only a code for the front right wheel speed sensor


What I’ve Already Tried:
• Transmission fluid change (no improvement).
• Scanned for fault codes (none found).
• Took it to two different shops. They didn't find anything wrong and told me its normal.

Are you sure you used the correct transmission fluid? The transmission is little more than a hydraulic pump, if you used fluid that's too heavy then this could affect the operation of the solenoids that do the gear selection things. Yes, there are more things than a hydraulic pump, but the point is valid, if you did not use the correct fluid then you can have solenoids that are not routing fluid to the right places at the right time.

ALSO, the Sport Mode changes the personality of the transmission, if you are using DS (Drive - Sport) instead of D, then the transmission will upshift later and downshift earlier. To use Sport Mode, you move the gear selector to the left (USA) and the display on the speedometer will say DS. From this position, you can move the selector fore and aft to manually change the gear selection -- the display will become M1 thru M6, depending on the gear you have manually selected.

How do you judge "engine braking" and ascertain that it is more aggressive?