Skip the auto shop - Our mechanics make house calls

Q: Transmission problem?

asked by on

Well the car jerks sometimes when changing gear. More when putting in reverse. There's also a sort of thumping on the passenger side front when the car is moving slowly or turning right. PLEASE HELP!!

My car has 147000 miles.
My car has an automatic transmission.

This kind of reaction is often a sign of low transmission fluid or a faulty transmission control solenoid. As you know, automatic transmissions use pressurized hydraulic fluid to change gears. Every time a gear change is required, the car’s computer activates a transmission solenoid, which directs transmission fluid into the valve body to engage the correct gear. When this is faulty or not working properly, this can cause a delay in gear shifting or in some cases cause the car to not shift at all. This type of problem is amplified any time the transmission is low on fluid creating a drop in hydraulic pressure.

This may also indicate a failing speed sensor. The transmission speed sensor is a magnetic sensor that provides information related to the speed of the input and output shafts in the transmission, allowing the transmission to shift smoothly. The sensor counts the internal number of revolutions of the transmission and transmits that information to the transmission control unit, where the data is used to determine the rotational speed. As the rotation increases, the control unit directs the changing of gears. When this is not working properly, this may cause the transmission to shift erratically or in some cases not at all. I would recommend having an expert from YourMechanic come to your location to take the car for a test drive to more specifically determine the cause for this.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: driver's door ajar light will not go off, computer not working, reset button does not work

The drivers door ajar switch is mounted on the door latch inside the driver's door. If you check the striker where the latch hits in the door jam to see if it was moved. You should be able to see...

Q: Hello hi, I have a 2009 Jeep Grand Cherokee 3.7 liter there is a problem with my truck that I can't figure out when I get stuck in

Hello there. Sometimes when the engine gets hot under the hood, electrical and ignition components can become 'touchy' and cause starting issues as you have described. In most cases, the issues are caused by faulty electrical connections between a wiring...

Q: Traction control light flashes when taking off slow. Also, grinding noise when pulling off fast or going up an incline or driveway

The traction control in the vehicle uses the brakes to control the wheel spin. If you are getting a light coming on and a noise during acceleration, your vehicle may be having an internal transmission problem with the 1st and...

Related articles

Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...