Kia Sorento Transmission Problems [9 Common Issues]

In this post, I’ve covered the common problems with Kia Sorento transmission and how to go about them.

If that sounds like what you’re looking for, let’s dive in!

Table of Contents

Kia Sorento Transmission Problems

1. Slow shifting when driving uphill

One common sign of a transmission problem in a Kia Sorento is a delayed gearshift when you drive uphill. The main culprit behind this issue is a bad alternator.

An alternator charges your vehicle’s battery. So, if you have a bad alternator, your vehicle’s battery might be weak.

Since your engine rarely sources power from your battery, a low battery may not affect your transmission’s performance in most driving conditions.

In contrast, your Kia Sorento requires additional power when driving upward. The car generates this extra energy from your battery.

So, if your battery is weak when you’re going uphill, your transmission may take longer to shift gears.

You’ll need to change your alternator to fix this issue. Find your alternator at the front of your engine.

2. Transmission slips

If your transmission keeps shifting from gear to gear after you press your gas pedal, the transmission may be faulty.

Although transmission slips often occur during acceleration, you might also encounter the issue while you are driving at a constant speed.

When you try to increase your speed, the RPM might go up, but the engine won’t accelerate until after you’ve driven for several minutes. Once your tranny changes to a higher gear, the RPM may come down again.

If you turn off your engine for several minutes, the transmission may become stable for a while. But after some hours, it may resume slipping again.

Kia dealers recommend changing your transmission fluid to fix this problem. According to them, Kia Sorento transmissions tend to slip if you don’t change the transmission fluid after every 30,000 miles.

A dealer will charge you about $200 to change the transmission fluid in your Kia Sorento. But if you want to save money, you can do it yourself.

You’ll find your transmission fluid pan at the bottom of your car. Make sure to drain the old fluid out before refilling the pan. Also, check that your new transmission fluid has OEM approval before buying it.

3. Rough shifting

You can tell that your Kia Sorento transmission is bad if it shifts roughly when you increase your speed. It will feel like the metal parts in your car are hitting each other. In addition, your vehicle may start shaking vigorously when you accelerate the engine on highways.

This problem usually occurs when the transmission is between its 4th and 5th gear.

Your transmission might shift roughly because the splines on your driveshaft joints are hitting the transmission. The driveshaft is the long tube at the bottom of your car that connects your transmission to your differential.

When you are speeding on the highway, the driveshaft joints hit harder on your transmission, and this causes your vehicle to shake.

You can resolve this problem by lubing your driveshaft splines. We recommend using the Valvoline Grease for U Joint lubricant to oil the joints.

If the transmission keeps shaking after you’ve oiled your driveshaft splines, the support bearing on your driveshaft may be faulty. The center support bearing on your driveshaft keeps the tube in place while your car is moving. Once this bearing loosens, your driveshaft may shake frequently.

To fix this issue, you’ll need to replace the support bearing on your driveshaft. We advise that you ask your dealer to change your bearing. Removing the bearing involves so many technicalities that even some mechanics can’t change the component without damaging it.

Before you change the bearing, you should confirm that it is really faulty. Your center support bearing is the U-shaped metal bracket at the center of your driveshaft.

Here’s how to inspect the center support bearing on your driveshaft:

Push the support bearing onto the floorboard.
If the bearing moves up to an inch, it has developed a fault.

But if the support bearing doesn’t move, something else might be wrong with your transmission. In that case, you’ll need to contact your dealer for help.

4. Tiptronic gearbox is stuck in low gear ratio

If your gearbox won’t shift from low gear no matter how much you push on your accelerator pedal, your transmission is faulty. While driving your car in this condition, the axle symbol may flash on your display, and the transmission might jump to Neutral gear. So, you won’t be able to drive fast.

Your gearbox is stuck in low gear mode because your Transmission Control Module (TCM) has gone bad. The TCM in your Kia Sorento monitors the speed of your car and determines when to switch gears. Then, it automatically steers the gearbox from high to low, or low to high.

If your TCM is faulty, your gearbox can’t shift gears on its own. Luckily, the Kia Sorento uses a Tiptronic gearbox. So, you can change gears manually in the car.

If your gearbox gets stuck again, use the transfer case shift motor on your gearbox to move from a low gear to a higher gear. This motor looks like a windscreen wiper motor, and it is located on the outside of the gearbox.

If you can’t locate the shift motor, just switch off your ignition and restart the car. This should resolve the problem temporarily.

The only permanent solution for a gearbox that gets stuck frequently is to replace the Transmission Control Module. You can easily change your TCM by yourself. Locate your TCM behind your transmission.

5. Display doesn’t reflect PRNDL gears

Another indicator of a bad transmission in a Kia Sorento is if your display doesn’t show when you put your car in a PRNDL. In addition, your engine may release a clunking noise when you shift gears.

You may also discover that your doors lock when you shift to Reverse, and the doors unlock when you switch to Park. If you try to restart the car while it is in Park, it may not start.

The most likely culprit behind this issue is a dirty inhibitor switch. The inhibitor switch prevents your engine from starting when your car isn’t set to Park or Neutral. Once you shift to the Park or Neutral gear, the inhibitor switch automatically disengages, so your engine can come alive.

However, if dirt gets stuck in the switch, it might not detect that you have changed your gear to Park.

To fix this issue, you’ll need to clean your inhibitor switch.

Here’s how to clean an inhibitor switch:

Remove your switch from the top of your gearbox.
Extract the dirt on the switch with a clean rag.
Then spray some contact cleaner over the button before re-attaching it to your gearbox.

Now, put your car in Park and try starting it. Your car should start now.

However, if the vehicle fails to start, your transmission range sensor might be faulty.

Your transmission doesn’t switch gears immediately after you change it on your gearshift. Instead, the transmission range sensor informs the Powertrain Control Module (PCM) what gear your shift selector is set to. Based on this information, the PCM engages the new gear in your transmission.

If your transmission range sensor is malfunctioning, it won’t inform your PCM that you’ve changed the position of your shift selector to Park. As such, your inhibitor switch and the rest of your transmission will think that your car is still set to the previous gear.

Change your transmission range sensor to resolve this problem. You’ll find this sensor at the top of your transmission.

6. Shift shock on slow speeds

If your transmission suddenly shifts from one gear to another while you are driving at low speed, there might be a problem with the device. It may feel like the transmission is delaying the shift at first. But then, the change will happen instantly, making it seem like a shock.

Shift shocks often occur when the tranny moves from the first gear to the second gear. During these shifts, you may hear a loud clunking noise from the engine.

A transmission failure is the most common reason for a shift shock. So, if you take your Kia Sorento to a dealer, they’ll suggest a transmission adaptive relearn before exploring other possible problems.

A transmission adaptive relearn is a mechanism that resets the adaptive settings in your transmission and trains it to learn a new shift time. This procedure is similar to the factory reset of a device.

The adaptive relearn will remove the issues in your transmission, forcing it to work on a new slate. This should eliminate your transmission failure.

If you still encounter a shift shock after the relearn, your transmission might be broken. As such, you’ll need to replace the entire transmission.

7. Transmission fluid leaking

Is your transmission fluid leaking from your Kia Sorento? Then your transmission is problematic.

Transmission fluid leaks may indicate that the front pump in your transmission is broken. The front pump moves the transmission fluid to other parts of the transmission. Because your front pump is leaky, your transmission fluid may spill out of the system before it can circulate through the transmission.

To fix this issue, you’ll need to change your transmission assembly. This includes the following:

Torque converter
Torque converter clutch
Front pump
Transmission casing
Turbine
Stator
Planetary gears
Brake bands
Clutches.

8. Shifter makes clicking noise when set to Drive

If you keep hearing a clicking noise when you set your shifter to the Drive gear, your transmission is faulty.

This problem might signify that your shifter assembly has reached the end of its lifetime and needs a replacement.

Once you get a new shifter, you shouldn’t hear the clicking noise anymore.

9. TCM error appears on radio

You can be certain that your transmission is bad if you see the P0705 TCM error on your radio. Usually, this error appears with a solid yellow engine light. Just as the error comes on, your car shift indicator may disappear. You may also notice that the car starts rolling as it is set to Neutral.

This issue is often caused by a broken transmission range switch. Your Kia Sorento relies on this switch for information on the gear your shift selector is set to. A bad transmission range switch may give your car the wrong gear information, thus causing the vehicle to misbehave.

The only fix for this problem is to change the transmission range switch. Locate this switch outside your transmission box.

Kia Sorento Models with the Most Transmission Problems

The following Kia Sorento models have the highest number of transmission issues:

2011 Kia Sorento
2016 Kia Sorento

According to car complaints.com, the 2011 Kia Sorento has the highest number of transmission problems among all model years. Eighteen users of the model reported problems with their transmission systems.

Another Kia Sorento model with many transmission problems is the 2016 model, which garnered ten transmission-related complaints from its drivers.

Kia Sorento Models with the Least Transmission Problems

2003 Kia Sorento
2005 Kia Sorento
2008 Kia Sorento
2009 Kia Sorento
2010 Kia Sorento

Carcomplaints.com states that no one reported transmission problems with the models above.

Cost of Fixing Kia Sorento Transmission Problems

It costs between $100 – $300 to fix the average transmission problem in a Kia Sorento.

Tips to Prevent Kia Sorento Transmission Problems

Change your transmission fluid after every 30,000 miles.
Warm up your car before driving it.
Service your powertrain transmission every year.
Make sure to shift gears correctly.
Remember to engage your parking brakes when stopping the car.

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Wrapping Up

Your transmission should resume working normally after you’ve applied the recommended solutions in this article. However, if the problem returns after you’ve tried the fix, contact your dealer.