The Reasons for Manual Transmission Won’t Go into Gear When Running

The transmission of a car controls the transfer of power from the engine to the driveshaft. It’s a complex mechanical system that is more susceptible to wear and tear than other components because of the huge amount of friction and heat it has to endure. Even a well-maintained gearbox is likely to undergo problems depending on your driving habit, mileage, and some other related factors. One such problem is manual transmission won’t go into gear when running.

Manual Transmission Won’t Go into Gear When Running: The Symptoms

Any repair or replacement of the transmission components is inconvenient, time-consuming, and requires a handsome amount of money. So, you should be on alert for unusual activities to detect a glitch at the primary stage.

When the transmission won’t shift gears despite the engine is running, you should immediately have it diagnosed by an expert mechanic. The signs that the car will show at this time are:

The transmission won’t shift and the car makes a grinding sound when the engine is running. Besides, pulling out of first gear will feel harder than normal.
The transmission will shift in and out of gear without any issue when the car is not running.
It won’t come out of the reverse gear when the car is running.
You can push the clutch to the limit but the engine almost halts upon allowing the clutch out.

The Reasons For Manual Transmission Won’t Go into Gear When Running

There are some specific reasons for the manual transmission to behave in that way. Let’s check if your car is having issues in these areas:

1. Look into the clutch

The problem could be the result of a stubborn clutch refusing to disengage. One way of checking it is to start the car after engaging the gear and clutch. If the vehicle stumbles forward, you should take it to a servicing shop. An experienced mechanic should diagnose the clutch system because it indicates that the hydraulic clutch is not putting any pressure on the pressure plate.

Like the braking system, most clutch systems will use hydraulic fluid to transfer the force you apply to a pedal into the cabin. This force pushes on the clutch fork which then pushes the pressure plate springs. If the clutch fluid is low, you can’t transfer this force from the clutch pedal properly. This could make it difficult to take off from a traffic light and hard to get into the gear.

Be careful not to do the clutch testing in a busy area. The car will lurch forward suddenly when you turn on the engine. So, choose a vacant place where there is no chance to hit anything or anybody.

A stubborn clutch is a symptom of this problem. (Photo: carthrottle.com)

2. Low level of transmission fluid

The components in a modern manual transmission are always in motion even when the gears are in neutral. If there is no lubricant in the gearbox, you could have done major damage to the engine and gearbox components by running the car. You could end up with an expensive repair and even replacement of the whole transmission system.

3. Damaged gears

There are lots of gears in a manual transmission system (1st gear, 2nd gear, 3rd gear,… or even 7th gear). There’s also a hub gear that goes between 1st gear and 2nd gear). If any one of these gears becomes damaged or worn out, you may have trouble shifting.

4. Damaged master cylinder

The clutch system consists of a variety of components. There is a clutch master cylinder, the clutch cover, the release fork, etc. If any of these parts is damaged, particularly the master cylinder then you may have difficulty shifting gears.

5. Failed synchronizer ring

The synchronizer ring has a lot of small teeth which allow the hub sleeves easily to engage it so it can go into one of the main gears. Synchros have made the practice of double clutching. When this part fails or is worn, it won’t be able to engage with the hub sleeve. As a result, you will encounter a shifting issue.

6. Bad shifter cable

Many vehicles don’t have a direct shifter linkage due to packaging reasons. This means the transmission and shifter are located in different parts of the car. On the vehicle architecture, a shifter cable is used to link the shifter lever and the transmission shift fork. If your shifter cable is stretched or misaligned, you have trouble putting the car into gear.

How To Fix Manual Transmission Won’t Go into Gear When Running?

In case the car has trouble getting into gear while driving even though the clutch pedal is fully depressed, the main reason is that the clutch is not cut off definitively. This is the intermediate bridge between the engine and the transmission and the active bridge in the powertrain. Therefore, if the clutch has a problem, it will cause many difficulties in controlling the car, even inoperable.

The car owner needs to check the operation of the clutch. The easiest way to check is to start the engine, set the gear, and release 1/2 of the clutch pedal (clutch foot). If the car moves smoothly, without jerks, and when accelerating, the car accelerates quickly, then the clutch is still in good condition.

In addition, you can also start the engine, pull the handbrake, press the clutch pedal, and set the 4th gear, slowly let go of the clutch pedal and slightly increase the throttle to be able to check. If the clutch works, the engine will stall when we let go of the clutch pedal. In case the engine is still running normally, it shows that the clutch disc is slipping due to wear.

Another way you can try is to start the engine, press the clutch pedal, put the first gear, and release the clutch while increasing the throttle. If you hear the engine rumble and the car moves poorly, the clutch may be worn. But to diagnose the most accurate condition, drivers should still give the car to trusted service centers to accurately assess the condition of the clutch on the car.

Watch the video to know more:

Conclusion

The best way to stay away from transmission problems is to follow the recommended maintenance schedule and regular checkup procedures. A well-maintained transmission will perform better and have a longer lifespan.