9 Reasons Your Transmission Won’t Go Into Gear
Your transmission is the part of your vehicle’s drivetrain that transfers power from the engine to the wheels. Having problems with your transmission can prevent you from driving your car. Here are some common reasons why it won’t go into gear.
Why won’t my car go into gear?
Transmission problems have different causes depending on whether you have an automatic or manual transmission. Some components that cause shifting difficulties have nothing to do with the transmission at all. Before rebuilding or replacing your transmission, here are some common causes of shifting problems in both transmission styles:
Automatic Transmissions
1) Faulty Shift Lock Solenoid
A shift lock is a part of the transmission that locks out when you can’t use other gears. For example, you might only want to be able to shift out of Park when you press the brake pedal.
The shift lock solenoid is an electrical device that tells the lock when to unlock the shift lever. If your shift lock solenoid is bad, you won’t be able to shift into gear from Park or Neutral.
2) Faulty Brake Switch
The brake switch is a special switch that tells your car when you press the brake pedal. This switch is especially important in automatic transmissions because they creep when you put the transmission in gear.
To prevent unwanted movement of the vehicle, manufacturers require that you press the brake pedal before shifting out of Park. If you can’t shift out of Park, pull the brake switch to test it. A faulty brake switch will often cause the check engine light or brake lights to stick.
Most brake switches are easily accessible, so if you have a multimeter, this is an easy DIY job. They are usually located near the pedal assembly.
3) Faulty Shift Linkage
Many automatic transmissions use a cable to change gears in the transmission. It’s the cable that connects to the shifter. If this shift rod comes loose, the shifter will move slightly between gears, but the actual gear in the transmission will not change.
Manual Transmission
4) Low Clutch Fluid Level
The majority of manual transmissions use a hydraulic system to disengage the clutch. If the clutch fluid level is low, it may not be possible to apply enough hydraulic pressure to the pressure plate to disengage the clutch.
If the clutch does not disengage, it will be very difficult (and sometimes impossible) to shift gears with the engine running. The clutch fluid level can be checked in the clutch reservoir in the engine compartment. Some vehicles use a fluid reservoir between the brake and clutch.
5) Clutch Pedal Assy
Your car may not go into gear because of a problem with the clutch pedal. Perhaps the pedal assembly is bent, preventing the clutch from disengaging completely. Check to see if the pedal is working properly.
6) Broken Pressure Plate Spring
The pressure plate is the part of the clutch system that separates the clutch from the flywheel, allowing them to spin at different speeds. If one or more pressure plate fingers are damaged, you may not be able to fully disengage the clutch even if the hydraulics are working properly.
7) Faulty slave cylinder or faulty clutch fork
The slave cylinder is the part that transfers pressure from the clutch hydraulics to the clutch fork when you press the clutch pedal. The clutch fork is the lever that physically separates the pressure plate from the flywheel.
If the clutch fork becomes disengaged from the slave cylinder or the slave cylinder is defective, the clutch will not disengage at all. This means you will not be able to shift gears while the car is moving (unless you’re already driving, in which case clutchless shifting may be possible). 8) Faulty Shift Cable
Like automatic transmissions, many manual transmissions use a shift cable to transfer motion from the shifter in the cabin to the transmission. This is especially true in vehicles with front-wheel drive, transverse engines, and transaxle drive.
If the shift cable breaks or comes undone, you won’t be able to shift gears; the shifter will be able to move freely with little or no resistance.
9) Honorable Mention: Poor Dubbing
A synchronizer, or “synchronizer,” matches the speed of each selected gear to the transmission’s output shaft when shifting from one gear to the next. If the synchronizer is defective, you may have difficulty shifting into a particular gear. Normally, it won’t matter what gear you shift into, but it will only shift into that particular gear because the synchronizer device will wear out in that one spot.