We seldom think about our automatic transmissions, as they work seamlessly most of the time.
Apart from the occasional need to top up a transmission fluid reservoir, there’s very little maintenance that is required.
So, when there’s a problem with the automatic transmission, it can be a little surprising as well as concerning.
Automatic transmissions are more complex than the gearbox on a manual transmission, and that makes it a little more difficult to diagnose the source of the problem.
Table of Contents
Car Jerks When Shifting from Park to Drive – Reason & Remedies?
When a car jerks when shifting from Park to Drive, it could be due to a low level of dirty transmission fluid or transmission pump failure. Fixing the problem could be as simple as topping up the transmission fluid. But the transmission fluid filter may also be blocked, or a sensor may be misaligned.
The transmission fluid level is low
If your transmission fluid levels are low, there is usually an engine check light that comes on or an error code will appear.
In modern cars, it is quite common for sensors to become misaligned or fail.
If this is the case, fixing the problem is as simple as running a diagnostic check, identifying the culprit, and replacing that sensor.
The fix is usually quick, simple, and cheap.
If you are unlucky, then a solenoid may have failed, in which case the repair may be a little more expensive.
5 Common Transmission Problems
Low Transmission Fluid Levels
While the transmission may use a little bit of transmission fluid over time, it is unusual to suddenly experience a drastic drop in the fluid level.
This usually indicates that there is a leak somewhere. Check under the vehicle to see if you can see a dark red stain or puddle where the car is parked overnight. Transmission fluid is a very distinctive red color and it is easy to identify.
The early indications are that the car will struggle a little to change gear with a little bit of jerking around before the car goes into gear. If this gets worse, then it’s a sure sign that there’s a problem and it’s a good idea to check your fluid levels.
Dirt or Debris in the Transmission Fluid
As your transmission changes gears, they grind away at each other. Very tiny amounts of metal break loose and enter the transmission fluid.
Transmission fluid is also hygroscopic. What this means is that it attracts moisture. Both water on the road and in the atmosphere makes its way into the transmission fluid, causing the fluid to lose some of its hydraulic properties.
This makes it more difficult to build pressure, which makes shifting gear a little more difficult.
All of this wear and tear together with contaminants that may have entered the transmission fluid result in it not being able to do its job properly. At that time, you need to drain the transmission fluid and refill the system with brand-new transmission fluid.
A Clogged Transmission Filter
The transmission filter’s job is to prevent debris from entering the system and physically damaging the gearbox.
The particles are usually pieces of metal that have worn away during normal use. As the filter becomes clogged, the transmission pump has to work harder and harder to develop the pressure necessary for the system to work. Eventually, the pump fails and your transmission will not change gears at all.
You generally have a bit of a warning that there’s a problem when your car jerks when changing gears or struggles to change gears at all.
Checking and changing the filter can solve the problem and is usually done when the fluid is completely replaced.
Transmission Pump Failure
An early warning sign that your transmission pump is about to fail is a jerky gear change accompanied by a high pitch whining every time you try to change gears or put the vehicle into Drive from Park.
It is also likely that the engine check light will come on to alert you to the impending problem. If your transmission filter was clogged, then you can be sure that the pump was working overtime to make up for the loss in pressure. The additional strain on the pump caused by the blocked filter will quicken the pump’s demise.
Allowing the filter to get blocked can cause serious wear to the gearbox and its associated parts, so replacing the filter each time you replace the transmission fluid can save you an expensive repair bill.
Worn Out Components
The automatic transmission on modern cars has to deal with powerful engines that put a huge strain on the components. As with most parts of the car, aggressive driving, rapid pull-aways, and speeding all cause excessive wear on the drivetrain.
Accelerated wear will manifest itself in many ways, one of which is a jerky gear change. This is an indication that the various components are reaching the end of their lifespan and must be replaced.
Fix the Problem Early
Transmission problems are initially easy to ignore. The problem will get progressively worse though, and could potentially leave you stranded.
The longer the problem persists, the greater the chances are that something expensive will get damaged when the gearbox finally breaks completely. It is better to have the problem looked at early and have worn-out parts replaced ahead of time than to leave it and risk an expensive repair later.
Service Your Transmission Regularly
Checking and changing your transmission fluid should be done as part of your regular maintenance. The owner’s manual will indicate when the transmission fluid should be changed and the number of miles between services.
It is common for the fluid change interval to be around 30,000 miles. However, if the fluid is dirty, then changing it sooner is a safer option.
There are some vehicles that can run for a lot longer without changing the transmission fluid, but your mechanic is the best person to decide whether the transmission fluid is ready to be changed.
Frequently Asked Questions About Car Jerking When Shifting from Park to Drive
How do I know if my transmission fluid is low?
You know that your transmission fluid is low when the car jerks when changing gear. The transmission will develop a high-pitched whine and you’ll experience poor acceleration. You’ll also most probably see the engine check light and transmission warning light coming on.
What happens if you drive with low transmission fluid?
While you may still be able to drive the car with low transmission fluid levels, every mile that you travel will cause damage to the gearbox. You will likely cause serious damage that will be expensive to repair.
How long will a transmission last without fluid?
You can probably drive 10-15 miles with low or no transmission fluid. After that, the build-up of heat will cause the gearbox to seize, which will cause permanent damage, requiring a replacement gearbox.
Conclusion On Car Jerks When Shifting from Park to Drive
An automatic gearbox will eventually require a change of transmission fluid to prevent damage to the gearbox and its components.
By the time the car starts to jerk whilst changing gears, the fluid levels may already be too low. Other components can fail, but regular maintenance will help to prevent an expensive repair bill.