Automatic Transmission Assembly for 2014-2015 Kia Optima
Product Notes Read before buying
This transmission fits 2014 and 2015 Kia Optima models with a 2.4L engine. It is for US-built vehicles only (8th VIN digit '7'). For 2015 models, this part only fits vehicles with a production date up to August 18, 2014.
Voice or type your vehicle details and Wrenchy will confirm fitment in seconds.
Vehicle Fitment Guide
This part fits the following vehicles:
| SubmodelSUB- MODEL |
Body Style | Years | Engine | Attributes |
|---|---|---|---|---|
| EX | Sedan | 2014 - 2015 | L4 2.4L | FWD | Automatic |
| EX Luxury | Sedan | 2014 - 2015 | L4 2.4L | FWD | Automatic |
| Hybrid EX | Sedan | 2014 - 2015 | L4 2.4L FULL HYBRID EV-GAS (FHEV) | FWD | Automatic |
| Hybrid EX Premium | Sedan | 2014 | L4 2.4L FULL HYBRID EV-GAS (FHEV) | FWD | Automatic |
| Hybrid LX | Sedan | 2014 - 2015 | L4 2.4L FULL HYBRID EV-GAS (FHEV) | FWD | Automatic |
| LX | Sedan | 2014 - 2015 | L4 2.4L | FWD | Automatic |
| SX | Sedan | 2014 - 2015 | L4 2.4L | FWD | Automatic |
Know This Transmission Before You Buy
The research behind our purchase interview — recalls, bulletins and real install economics for this transmission family:
A quick look at your own vehicle makes sure the right transmission shows up:
- Verify your VIN's 1st Character starts with 5 (US-built).
- Verify your VIN's 8th Character is 7 (2.4L naturally aspirated engine).
- Verify your vehicle is Front-Wheel Drive (FWD).
- Verify the etched ID code on the top of your transmission case starts with EA or FA.
What the install really takes — plan and budget with confidence:
Special tools this job needs:
- Engine support bar
- Transmission jack
- Professional-grade bidirectional scan tool
Budget for these consumables at install:
- Hyundai/Kia ATF SP-IV (or SP4M-1, or equivalent fluid explicitly meeting this specification)
- Torque Converter Seal (OEM Part # 46131-3B000 or equivalent)
- Left and right CV axle/differential seals
- Aerosol transmission cooler flush (such as Lubegard Kooler Kleen)
- Transmission pan gasket (if pan is removed for inspection)
What your vehicle’s computers will need after the swap:
What’s involved: TCM Adaptive Relearn (Resetting Auto Transaxle Adaptive Values)
A TCM adaptive relearn procedure is mandatory after replacement to teach the controller specific clutch engagement points. Skipping this can cause severe shifting issues and burn out the clutches. While some basic resets can be attempted without one, a proper relearn is best done with a capable diagnostic scan tool (such as Kia GDS, Autel, or Snap-on).
Pro tips for a smooth first start-up — hand them to whoever does the install:
- Torque Converter Seating (CRITICAL): Must be fully seated onto the input shaft and oil pump gears (clicking/dropping 3 times) before bolting to the engine. Forcing it will crack the oil pump gear, destroying the transmission instantly.
- Engine Alignment Dowel Pins: Ensure two alignment dowel pins are present in the engine block to prevent misalignment, which causes rapid wear of the front pump seal and torque converter bushing.
- Fluid Level Check Procedure (CRITICAL): No dipstick. Check via overflow plug on the plastic side cover with vehicle level, engine idling in Park, and fluid temperature between 122°F and 140°F (50°C - 60°C).
- Plastic Side Cover Warping: Valve body cover is plastic. Do not overtighten bolts (torque spec is 7 to 9 lb-ft) to prevent warping and leaks.
- Ground Straps: Ensure all grounding straps between the engine, transmission, and chassis are clean and securely reconnected.
Easy to get right once you know them:
- Ordering the Wrong Build Origin (US vs. Korea): Ordering this US-built transmission (VIN starting with 5XX) for a Korean-built Optima (VIN starting with KNA).
- Bolting the Torque Converter to the Flexplate First: The torque converter must be installed and fully seated onto the transmission first, then bolted to the flexplate through the starter pocket access hole.
- Skipping the Adaptive Reset: Driving the car without resetting the TCM adaptive values, causing the computer to apply old high-pressure adaptations to the new unit.
- Using Generic ATF: Using generic 'multi-vehicle' fluids that do not explicitly meet the strict SP-IV specification.
- Assuming All 'A6' Transmissions are the Same: Ordering similar-looking A6-family transmissions (like A6GF1) which have different mounting brackets, bolt holes, and gear ratios.
Not issues with the units on this page — the manufacturer documented these for every transmission of this family, wherever you buy one. Handy for your installer:
🔎 Recommended at install: Inspect the internal harness and sensor before installation, or replace if any codes are present.
🔎 Recommended at install: Ensure you install a functioning inhibitor switch on the replacement transmission.
🔎 Recommended at install: Caused by rough surface finish inside the underdrive brake drum from the factory; requires internal rebuild/inspection.
🔎 Recommended at install: Bores wear out over time causing drop in line pressure; requires valve body repair or replacement.
🔎 Recommended at install: A software update for the Transmission Control Module (TCM) is available from the dealer to correct hard downshifts, upshifts, or shift delays.
🔎 Recommended at install: A pump bolt can obstruct a drain passage causing the front pump seal to leak. Replace the front torque converter seal.
Researched from factory recalls, TSBs and OEM service data (reference unit 400-62621-2264337). Unit-specific details — mileage, condition, warranty, freight — are covered in the checkout interview.
Policies, in plain English.
Shipping & Handling
- Ships by LTL freight on a pallet — a real freight truck, not a parcel van
- Your checkout freight quote covers delivery to your door (liftgate service included for residential addresses)
- The carrier calls ahead to schedule a delivery window — someone must be present to receive it
- Typically palletized and picked up within 2–3 business days; transit time depends on distance
120-Day Warranty
This part includes a 120-day warranty.
- If the part fails within the warranty window, we'll replace it or refund per the coverage terms
- Coverage is parts-only — installation labor is not included
- Warranty covers defects — not installation errors, misuse, or damage after installation
Your pre-purchase interview reviews these exact terms with you before anything is charged.
Returns (30 Days)
We accept returns of uninstalled parts within 30 days of delivery for this part.
- Defective parts: We will replace the part or issue a refund at our discretion
- Programming: "Needs to be programmed to my vehicle" is not a valid return reason. Many modules require dealer programming — we're happy to help connect you with resources if your dealer says it's not programmable
- Return shipping: This part ships by freight (LTL) — the part price is refundable per the terms above, but shipping costs are non-refundable and return freight follows the seller's return terms. Your pre-purchase interview walks through the exact numbers before you buy
- Parts must be returned in original packaging and unmodified condition
- Poorly packaged returns that arrive damaged will not be credited
Damaged in Shipping?
Freight damage is rare — and you're fully protected when you do two things at delivery:
- Inspect before you sign — you're allowed time to look the pallet over while the driver waits
- Write any damage on the delivery receipt before signing — that one line is what makes a freight claim succeed
- Severe damage? Refuse the delivery — it goes back at no cost to you and we make it right
- Photograph the pallet before unwrapping; report concealed damage within 24 hours of delivery
We handle the carrier claim — you just help document it. Your pre-purchase interview walks through this checklist too.
Order Cancellation
Cancel before shipment for a full refund. Once the pallet has been built, a preparation charge may apply — and once the freight carrier picks it up, shipping costs are non-refundable and standard return terms apply. Your pre-purchase interview shows the exact numbers before you pay.
Expert Guides
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Identify what kills the A6MF1 transaxle, diagnose common shifting issues, and learn exactly what to look for when buying a used OEM replacement unit.
Read Full Guide →Related Trouble Codes (OBD-II)
29 matching guidesIf your scan tool is showing one of these trouble codes, this part is a common fix. Each guide explains the code, how to diagnose it, and exactly what to replace.
Miscellaneous Information
OEM Part Numbers:
Kia: 450003B740, 450003B740R
Fits Years: 2014 2015
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This unit ships with the selling yard's 120-day warranty. Longer plans can be requested during checkout.
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