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Whether you’re a seasoned gearhead or a weekend warrior who prefers the passenger seat, this blog is your one-stop shop for all things reverse-related car trembles. We’ll dive deep into the mechanical culprits, from dodgy engine mounts to low transmission fluid, leaving no stone (or spark plug) unturned.
By the end of this blog, you’ll hopefully have the knowledge to soothe even the most temperamental of transmissions.
What Are The Potential Causes Of Your Car Shaking in Reverse? How To Diagnose The Issue?
A gentle hum might be expected when shifting gears in your car, but a violent shake? That’s not normal. If your car throws a wobbly fit every time you reverse, the culprit could be hiding among a multitude of suspects.
Let’s delve into the potential causes of your car’s shaky syndrome and how to diagnose these causes:
The Tremor Meter
First, calibrate your “tremor meter.”
- Slight Vibration: Engine mounts, exhaust, or suspension might be worn.
- Violent Shake: Transmission, driveshaft, or wheel alignment could be to blame.
Next, listen for grinding, clunking, or squeaking – each a clue to a specific problem. Remember, early diagnosis saves you headaches and car repairs!
1) Low Fluid Levels
Dive under the hood and crack open the transmission fluid mystery. Is it a shimmering pool reflecting the engine’s hum, or a puddle clinging to the dipstick’s bottom? Low fluid can starve your car’s gears, leading to jerky movements and frustrating tremors, especially when reversing uphill or pulling out of tight spaces.
To diagnose, consult your car’s manual – it’s your roadmap to the ideal fluid level. Grab a clean rag and carefully check the dipstick.
2) The Morning Sickness
Ever notice your car throws a wobbly fit only when you first put it in reverse? You’re not alone. Some transmissions suffer from a quirky cold-start condition known as “morning sickness.”
The telltale sign? If the shaking subsides after a few minutes of driving and returning to reverse, “morning sickness” might be the culprit.
3) Mechanical Issues
Listen intently! Does the shaking come with an unwanted and unrhythmic sound? Grinding, squeaking, or clunking noises are red flags for mechanical issues. Grinding might point to transmission woes, clunking could indicate trouble with the driveshaft or universal joints, and squeaking might hint at worn belts.
4) Over-Inflated/Under-Inflated Tires
Give your tires a thorough examination. Uneven wear patterns can cause vibrations, especially when reversing. Over-inflated or under-inflated tires can disrupt driving dynamics.
5) Inadequate Fuel Pressure
Does your car seem sluggish and hesitant when reversing uphill? This might be a sign of inadequate fuel pressure. The increased demand uphill exposes any fuel pressure issues that might go unnoticed on flat surfaces.
6) Clogged Filter
A clogged filter can be another cause for car tremors in reverse.
How to identify a clogged filter:
- Shaking in reverse, especially at low speeds.
- Harsh or delayed gear changes.
- Burning smell from the transmission.
7) Transmission Issues
Does shifting out of reverse feel like navigating a maze? Does the car respond sluggishly when engaging reverse? These could be clues for a lurking transmission problem, a frequent suspect in reverse-related shakes.
8) Other Root Causes That Are Causing Car Shaking In Reverse
- A Faulty TPS
- Torque Converter Trouble
- Faulty EPC Solenoid
- Throttle Body Issues
Uncovering The Solutions To Stop Your Car From Shaking In Reverse
Now that we’ve identified the culprits, let’s explore the step-by-step solutions to put an end to your car’s reverse shake.
Solution #1 – Replace Damaged Engine Mounts
If your engine mounts are the issue, replacement is the key.
Here are the general steps involved in replacing engine mounts:
- Locate the damaged mount: Inspect the engine mounts to identify the damaged one. Check for cracks, tears, or other signs of wear and tear.
- Consult your car’s manual: Look up the right part number for the engine mount in your car’s manual. Make sure to get the correct part for your specific make and model.
- Prepare the car: Park the car on a level surface and engage the parking brake. Open the hood and disconnect the battery.
- Support the engine: Use a jack and various blocks of wood to support the engine from underneath. Make sure to use two methods of supporting the engine for redundancy.
- Remove the old engine mount: Remove the bolts that hold the old engine mount in place.
- Install the new engine mount: Put the new engine mount in position and loosely thread the bolts in. Most engine mounts have a dowel pin that needs to be positioned.
- Position the engine and torque the mounts: With the bolts loosely threaded, make sure to position the engine properly from the top. Torque the mounts to the manufacturer’s specifications.
Solution #2 – Replace The Transmission Mounts
Similar to engine mounts, locate the torn transmission mount and replace it. A new transmission mount restores stability and eliminates vibrations.
The process for replacing a transmission mount involves the following steps:
- Gather the necessary tools and parts: Ensure you have the correct replacement transmission mount and the tools required for the job. Common tools include a jack, jack stands, wrenches, and sockets.
- Prepare the vehicle: Park the car on a level surface, engage the parking brake, and chock the wheels. For safety, disconnect the battery to prevent any electrical mishaps.
- Raise the vehicle: Use a jack to lift the vehicle and place jack stands under the frame for support. Ensure the vehicle is securely positioned on the jack stands before proceeding.
- Remove the old transmission mount: Unbolt the old transmission mount from the crossmember and transmission. Support the transmission with a jack during this process.
- Install the new transmission mount: Position the new transmission mount and secure it in place using the appropriate bolts. Ensure it is aligned correctly before tightening the bolts.
- Lower the vehicle and test: Carefully lower the vehicle from the jack stands and remove them. Reconnect the battery and start the engine to test the new transmission mount.
Solution #3 – Top Up The Transmission Fluid
Here’s how to get your ride smooth again by topping up the transmission fluid:
- Locate the transmission fluid dipstick (consult your car’s manual for guidance). It usually has a bright yellow handle.
- Pull it out and wipe it clean.
- Reinsert it fully, then pull it out again. Check the fluid level on the marked area of the dipstick.
If the fluid is below the minimum mark, top it up with the recommended type. Your car’s manual will specify the right fluid for your transmission. It’s usually labeled as “Dexron” or “Mercon,” followed by a number (e.g., Dexron III, Mercon V). Don’t guess, as using the wrong fluid can cause major problems!
If the fluid is dark or smells burnt, a complete fluid change is recommended. This involves draining the old fluid, replacing the transmission filter, and refilling it with fresh fluid.
A simple top-up can be done at home. Buy the recommended fluid and carefully pour it in through the dipstick tube until the level is correct.
A complete fluid change is more involved. You’ll need a drain pan, transmission filter wrench, funnel, and some know-how. It’s best left to a mechanic if you’re not comfortable working on your car.
Solution #4 – Replace Clogged Transmission Oil Filter
Here’s the lowdown on tackling the job yourself:
- Tools: Drain pan, wrenches (sizes based on your car’s manual), new transmission filter and gasket (if applicable), transmission fluid of the recommended type, funnel, rags, and gloves.
- Manual Instructions
- Park on a level surface, engage the parking brake, and chock the wheels for safety.
- Locate the transmission pan drain plug (usually near the bottom). Place the drain pan beneath and carefully loosen the plug. Hot fluid will gush out, so be prepared!
- Let the fluid drain completely. This can take 15-30 minutes.
- Once the fluid has drained, locate the transmission pan bolts around its perimeter. Using the appropriate wrenches, loosen and remove them one by one. Gently lower the pan and watch for any remaining fluid dripping out.
- Inside the pan, you’ll find the culprit – the old, likely grimy transmission filter. Carefully remove it, taking note of its orientation for proper installation of the new one.
- If your filter comes with a new gasket, replace the old one on the pan flange, ensuring a clean seal. Apply a thin layer of gasket sealant (if recommended in your manual) for extra assurance.
- Place the new filter in its slot, aligning it with the corresponding grooves or tabs. Gently push it in until it’s securely seated.
- Reinstall the transmission pan bolts in the reverse order of removal, tightening them evenly to the specified torque (check your manual).
- Using the funnel, carefully pour the recommended amount of fresh transmission fluid into the pan through the dipstick tube. Check the level regularly, stopping when it reaches the “Full” mark on the dipstick.
- Wipe up any spills and replace the dipstick. Close the hood and give your car a pat on the hood.
- Fire up the engine and let it run for a few minutes, allowing the fluid to circulate.
- Shift through all gears, including reverse, paying attention to any shaking or unusual noises. If all seems smooth, you’re good to go!
Solution #5 – Repair/Replace The Torque Converter
For a faulty torque converter, professional help is recommended. Consult a mechanic or transmission specialist for repairs or replacement, restoring seamless power transfer.
Solution #6 – Address The EPC Solenoid
Addressing a faulty EPC solenoid requires professional intervention. Seek a mechanic’s assistance to diagnose and repair or replace the solenoid, restoring proper transmission pressure.
Solution #7 – Understand Faulty Throttle Body Sensors
Before diving into sensor replacement, it’s essential to properly diagnose the issue. Here’s how to get started:
- Check the Engine Code: Many car models display diagnostic trouble codes (DTCs) when the Check Engine Light is on. These codes can point you towards specific sensor issues. You can read the code using an OBD-II scanner (available at most auto parts stores) or have a mechanic do it for you.
- Sensor Inspection: Once you have the code, consult your car’s manual to identify the specific sensor involved. Locate the sensor on the throttle body (usually a butterfly-shaped valve near the air intake) and visually inspect it for any damage or corrosion.
If the sensor shows signs of wear or the code confirms its malfunction, it’s time for a replacement.
Here’s what you’ll need:
- The correct replacement sensor
- Basic tools
- Your car’s manual
Here’s how to replace faulty throttle body sensors:
- Carefully disconnect the wiring harness and unbolt the faulty sensor from the throttle body.
- Slide the new sensor into its rightful place, secure it with the bolts, and reconnect the wiring.
- With the culprit replaced, reset the “Check Engine” light using your scanner or a quick visit to the mechanic.
- Take your car for a spin, paying attention to that reverse gear.
Solution #8 – Clean The Throttle Body
To clean your car’s throttle body, first gather the tools:
- Throttle body cleaner (choose one specific to your car’s material)
- Shop towels or rags
- Screwdrivers or wrenches (based on your throttle body mounting)
- Gloves and safety glasses (for eye protection)
Get down to business:
- Locate the throttle body: Consult your car’s manual for its specific location (usually near the air intake manifold).
- Disconnect the air intake: Depending on your car, you might need to remove some hoses or clamps to access the throttle body.
- Unbolt the throttle body: Loosen and remove the mounting bolts holding it in place. Be careful not to lose any gaskets or seals.
- Cover The Intake Manifold: Cover the intake manifold opening to prevent debris from falling into the engine during cleaning.
- Cleaning time: Spray the throttle body cleaner liberally onto the butterfly valve and surrounding passages. Use the rags to wipe away any loosened grime and carbon buildup.
- Rinse and repeat: If necessary, spray more cleaner and wipe again until the surfaces are clean and free of visible debris.
- Seal the deal: Let the throttle body dry completely before reassembling. Replace any gaskets or seals if needed.
- Reconnect and reinstall: Reverse the steps you took to remove the throttle body, ensuring everything is securely fastened.
- Reset the ECU: Disconnect the negative battery terminal for a few minutes to reset the Engine Control Unit and allow it to relearn the newly cleaned throttle body parameters.
- Reignite and check again.
- Reconnect the battery terminal and start the engine.
- Let the engine idle for a few minutes to stabilize.
- Take your car for a test drive, paying attention to gear changes, especially in reverse. You should notice a smoother, more responsive ride and hopefully, say goodbye to those unpleasant shakes!
Bonus Solution – Fixing Your “Car’s Morning Sickness”
If your car tends to shake in the morning, consider a gentle warm-up. Drive in lower gears for a few minutes after starting out to allow the transmission to warm up, providing a smoother reverse experience.
The warm-up period allows all the fluids and components to reach optimal operating temperature, leading to smoother gear changes and preventing those pesky morning shimmies.
In conclusion, understanding the root causes of your car’s reverse shake empowers you to take effective action.
Whether it’s a DIY cleaning task or seeking professional help, the above-listed solutions ensure a comfortable and shake-free driving experience.