This automotive maintenance tutorial was specifically written to assist owners of the third generation (2016, 2017, 2018, 2019 and 2020) Kia Sorento SUV in changing the serpentine accessory belt on the Lambda II GDI 3.3 liter V6 engine. (The procedure may be similar for the Theta II 2.4L I4 engine and the Theta II Turbocharged 2.0L I4 engine.)

Owners of other Kia, Hyundai and Genesis vehicles such as the Soul, Seltos, Sportage, Niro, Telluride, Forte, Rio, Optima, Stinger, Cadenza, K900, Sedona, Kona, Venue, Santa Fe, Elantra, Sonata, Accent, Veloster, Ioniq, Nexo, G70, G80 and G90 may also find these instructions to be helpful.

A few compatible replacement serpentine accessory belts for the Lambda II GDI 3.3L V6 engine with their part numbers are as follows: Gates K060747, Continental 4060747, Dayco 5060750 and ACDelco 6K747.

The tools required to complete this procedure include a 10mm socket with a 1/4" drive ratchet and a 19mm socket with a 1/2" drive ratchet.

The best way to access the belt is from the underside of the engine bay. You might be able to squeeze under the vehicle, but I chose to raise it for more working room.

Carefully raise the front of the SUV with the floor jack and securely support it with at least two jack stands.

Remove the bolts that secure the under engine cover or "skid plate" by turning them in the counterclockwise direction with the 10mm socket, a short extension bar and a 1/4" drive ratchet.

I've also included a rough drawing of the belt routing diagram below.

Attach the 19mm socket to the 1/2" ratchet or a long handled 1/2" drive breaker bar.

Locate the hex head "fake" / "false" / "dummy" nut on the tensioner assembly.

If you look at Picture # 19 in the row above, you'll see a red arrow pointing to the tension release nut on the tensioner arm situated just below the tensioner pulley.

Do NOT rotate the bolt at the bottom of the tensioner assembly with the number "10" printed on it. This bolt holds the tensioner assembly in place to the engine.

Place the 19mm socket over the false hex nut attached to the tensioner arm.

If you view Picture # 22, you'll see a red arrow pointing in the correct direction that you'll need to rotate the bottom of the ratchet or breaker bar.

As your rotate the ratchet handle towards the front of the SUV, the tensioner arm and pulley will rotate back towards the rear of the vehicle.

Hold the tensioner arm in the released position with one hand.

Very carefully use your other hand to slip the old belt off the A/C compressor pulley or the crankshaft pulley.

Do NOT place your fingers or hands in between the belt and any of the pulleys!

Slowly release the tensioner arm and allow it to swing back into its resting position.

Continue slipping the old belt off the other pulleys including the alternator, idler pulleys, water pump, crankshaft and A/C compressor.

If the old belt is still in decent condition, consider keeping it as an emergency backup part just in case the new belt fails prematurely.

The OEM belt was marked as part number Hyundai / Kia 25212-3LAA0 6 PK 1705 ContiTech (Made In Romania).

Check to see if the two idler pulleys and the tensioner pulley spin freely. If the pulleys are difficult to spin, make noise or wobble, the bearings might be worn out and the pulleys should be replaced.

The compatible replacement part numbers for the pulleys are as follows: Tensioner Pulley - Dayco 89133 and Idler Pulleys - Dayco 89164.

If the old belt was loose or the tensioner arm was very easy to rotate back, you may need to replace the tensioner assembly.

The tensioner assembly replacement part numbers include the following: Hyundai / Kia 25281-3C100 (252813C100), ACDelco 39104, Dayco 89654 and Gates 39104.

Lower a new compatible replacement aftermarket belt such as the Gates K060747 down into the engine bay.

Begin by wrapping the new belt around the large crankshaft pulley.

Hold the last loop of the new belt in place near the A/C compressor pulley.

With your other hand, rotate the tensioner arm back to the released position.

Very carefully slip the last loop of the new belt over the A/C compressor pulley.

Do NOT place your fingers or hands in between the belt and any of the pulleys!

I created a rough drawing of the belt routing diagram which is shown in Picture # 18.

Make sure that the ribbed side of the new belt is wrapped around the ribbed pulleys and the flat side of the belt is situated against the smooth tensioner pulley and two idler pulleys.

With your other hand, spin in the bolts a few turns by hand in the clockwise direction.

Carefully lower the SUV from the jack stands by using the floor jack.

Start the engine and listen closely for any strange noises.

If you do hear any strange sounds, immediately turn off the ignition and check the belt installation again.

Don't forget to write down the belt change in your vehicle's service records.

Please take a look at all of my 2016-2020 Kia Sorento DIY Repair & Maintenance Guides.