Q: Transmission intermittently won't shift to next gear

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My car has a SMG transmission. The problem began around 1 month ago and it is intermittent. Sometimes the transmission won’t shift at all, no matter which gear the car is in. Sometimes the gear that it is in won’t change. I have to take my foot off the gas pedal so that it will shift. When on the highway, if I go from first-second-third- then it won’t shift into fourth and I have to take my foot off the gas to get it to shift into fifth. One time, while changing gear with the paddle shift, it stopped at 2nd and a SMG light came on telling me to check the dealership. So I took the car to the BMW dealer and they ran a diagnostic on the transmission. They said that the transmission stopped at third gear and it didn’t shift any more. Then, they told me that I needed a new transmission. That doesn’t make sense to me since I can still shift the gear. The SMG doesn’t shift some times, even when on 5th and driving on the highway, it won’t shift into 6th until I take my foot off the gas. I’ve heard different analysis of the problem - computer - reset battery, etc. Do you think my car needs a new SMG transmission, and if not, what do you suggest?

It is very possible that the transmission may require a full rebuild or a replacement in order for it to perform properly. Although you are able to shift into other gears, if certain gears are not working correctly, transmission damage may be the cause.

If the transmission has already been diagnosed by the dealer that it needs replacement and the transmission is still not shifting properly, it is unlikely that the transmission will get any better without replacement.

It does not hurt to attempt any reset procedure that may be available, but it is also unlikely that a reset of any kind will resolve transmission issues. Small things to check before replacing the transmission if possible would be the fluid level and any trouble codes that may have been stored due to the issue your transmission is causing.

If any codes exist, this may lead you to other possible parts inside the transmission that may be able to be replaced and have your transmission working again as it should. You can get a second opinion from an local expert, such as one from YourMechanic, in order to diagnose your shifting problem and advise you on the next steps.

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