- First Name
- Tom
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- Los Angeles Metro
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- 2021 Bronco Sport
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Update
Over the past 3-4 months, I have been experiencing a stumbling issue. This occurs all the time between 25 and 45 mph under light to moderate throttle. When under hard throttle, the issue does not appear. There has also been a rhythmic surge at highway speeds. The tachometer would jump every second while driving.
My 21 OB has 117,000+ miles. The spark plugs were changed at 105,000. I cleaned the MAF, mass airflow sensor; the MAP, manifold absolute pressure sensor and the IAT, intake air temperature sensor. I used MAF cleaner on all three. I did not see any visible debris or discoloration. The engine air filter is clean.
Three weeks ago, while out of town, an MIL appeared on the dash (check engine light). I pulled into an O’Reilly Auto Parts. They read the code as P3402, cylinder deactivation solenoid. When arriving back, I had the dealer order and replace the cylinder deactivation solenoid.
After picking the vehicle up, the issue remained. I again dropped the vehicle off to be diagnosed, it ended up in the transmission area. I was told the torque converter is bad. New transmission replacement over $11,000. Rebuild the existing transmission over $8000 and torque converters are on back order.
I asked them to drain and refill the transmission fluid. I picked it up and it still had the issue.
The 8F35 transmission was co-developed with General Motors. I researched this and found the GM version has a known torque converter shudder issue. I searched for this same issue and found the Edge has a known torque converter shudder issue also.
The next day, I purchased Lubegard Instant Shudder Fixx and a funnel. I pulled the air box out and removed the cap from the transmission fill tube. Inserted the funnel and in goes the 2 oz of Instant Shudder Fixx. I reinstalled the air box and went for a drive. I was shocked. The torque converter shudder was gone right away. I continued the drive, making sure I included freeway driving, around 25 miles total. The vehicle was driving like new. The rhythmic surge is also gone.
I just repaired the issue for $15.45
https://www.lubegard.com/products/isf/
I feel that as more BS owners are accumulating over 100,000 miles, this issue will become much more common.
Do not assume that you need a new or rebuilt transmission. Try this as a solution first. I would recommend having the transmission fluid drained and refilled with new fluid before adding the Lubegard Instant Shudder Fixx. The 8F35 is not recommended to be flushed.
It is not possible to drain all the old fluid. However, by draining and adding new fluid you will dilute the old fluid with new fluid.
Over the past 3-4 months, I have been experiencing a stumbling issue. This occurs all the time between 25 and 45 mph under light to moderate throttle. When under hard throttle, the issue does not appear. There has also been a rhythmic surge at highway speeds. The tachometer would jump every second while driving.
My 21 OB has 117,000+ miles. The spark plugs were changed at 105,000. I cleaned the MAF, mass airflow sensor; the MAP, manifold absolute pressure sensor and the IAT, intake air temperature sensor. I used MAF cleaner on all three. I did not see any visible debris or discoloration. The engine air filter is clean.
Three weeks ago, while out of town, an MIL appeared on the dash (check engine light). I pulled into an O’Reilly Auto Parts. They read the code as P3402, cylinder deactivation solenoid. When arriving back, I had the dealer order and replace the cylinder deactivation solenoid.
After picking the vehicle up, the issue remained. I again dropped the vehicle off to be diagnosed, it ended up in the transmission area. I was told the torque converter is bad. New transmission replacement over $11,000. Rebuild the existing transmission over $8000 and torque converters are on back order.
I asked them to drain and refill the transmission fluid. I picked it up and it still had the issue.
The 8F35 transmission was co-developed with General Motors. I researched this and found the GM version has a known torque converter shudder issue. I searched for this same issue and found the Edge has a known torque converter shudder issue also.
The next day, I purchased Lubegard Instant Shudder Fixx and a funnel. I pulled the air box out and removed the cap from the transmission fill tube. Inserted the funnel and in goes the 2 oz of Instant Shudder Fixx. I reinstalled the air box and went for a drive. I was shocked. The torque converter shudder was gone right away. I continued the drive, making sure I included freeway driving, around 25 miles total. The vehicle was driving like new. The rhythmic surge is also gone.
I just repaired the issue for $15.45
https://www.lubegard.com/products/isf/
I feel that as more BS owners are accumulating over 100,000 miles, this issue will become much more common.
Do not assume that you need a new or rebuilt transmission. Try this as a solution first. I would recommend having the transmission fluid drained and refilled with new fluid before adding the Lubegard Instant Shudder Fixx. The 8F35 is not recommended to be flushed.
It is not possible to drain all the old fluid. However, by draining and adding new fluid you will dilute the old fluid with new fluid.
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