Walker
CalCat

Walker 84178 Catalytic Converter - Front

Brand Walker 84178
Position Front
Mounting Hardware Included No
Universal Or Specific Fit Specific
Grade Type Regular
Body Shape Round
Inlet Type 3 bolt welded flange
Outlet Type 4 bolt welded flange
Body Height 4.02
Body Height 4.020
Body Length 6.25
Body Length 6.250
Body Width 4.02
Body Width 4.020
Inlet Quantity 1
Body Material Stainless steel
Outlet Quantity 1
California Air Resources Board (CARB) Certified Yes
Substrate Material Ceramic
Overall Length 14
Overall Length 14.000
Air Tube No
Air Tube Count No
Converter Quantity 1
Inlet 1 Type 3 bolt welded flange
Inlet Type 3 bolt welded flange
Max Year Covered 2015
Min Year Covered 2013
Most Popular Make / Model Chevrolet malibu
Most Popular Year 2015
Outlet 1 Outside Diameter 1.995
Outlet 1 Type 2 bolt welded flange
Product line CalCat
Fits Chevrolet · 5 vehicles

CARB certified. Built to meet California emissions standards with assured compliance.

Direct-fit design. Delivers a precise OE-style fit for easier installation.

Stainless steel body. Ceramic substrate helps support efficient exhaust flow and durability.

Cross-references 551889 for the same application. See all 1.

$491.77Free shipping
In stock · usually ships same day before 1pm CST
Step 1 — Confirm fitment
Free return shipping if it doesn't fit when you check fitment here first.

Select your vehicle to confirm fitment
Verify this part fits before purchasing — free returns if it doesn't
Step 2 — Quantity
Order total $491.77
Free shipping to the continental U.S.
Free returns within 60 days if it doesn't fit when fitment is verified.

Walker CalCat Direct-Fit Catalytic Converter

Walker CalCat Part Number 84178 is a direct-fit catalytic converter built for CARB-compliant replacement on select Chevrolet applications. It is designed for a precise OE-style fit and is validated to meet California Air Resources Board standards for regulated emissions service.

Key Features

  • Direct-fit design for straightforward replacement on confirmed applications
  • CARB certified for use in California and other states that require CARB-compliant converters
  • Stainless steel body with a ceramic substrate
  • Round body shape with welded flange connections
  • Front-position fitment for select Chevrolet Impala and Chevrolet Malibu models
  • Walker CalCat line engineered for OBDII and non-OBD vehicle coverage

Product Details

This Walker CalCat catalytic converter is built for 2013-2015 Chevrolet Malibu, front; 2014-2015 Chevrolet Impala, front. The design uses a 3-bolt welded flange inlet and a 2-bolt welded flange outlet, with an overall length of 14 inches and a stainless steel body for durable exhaust service. Part number 84178 is also cross-referenced to 551889 for the same application.

The Walker CalCat product line focuses on direct-fit replacement converters that follow OE-style dimensions and emissions compliance requirements. For buyers searching for a 2015 Chevrolet Malibu front catalytic converter or a CARB-compliant replacement catalytic converter for a 2014 Chevrolet Impala, this part is built around the listed vehicle-specific fitment and emissions certification.

Common Problems This Part Addresses

  • Failed catalytic converter emissions test results
  • Check engine light concerns related to catalyst efficiency
  • Restricted exhaust flow from a worn or damaged converter
  • Replacement needs after corrosion or internal substrate breakdown
  • CARB compliance requirements for regulated-state vehicle service

Installation Notes

Exhaust gasket is recommended during installation. Additional parts needed to complete installation are 31616 and 31532. Confirm the vehicle’s engine family number and front-position application before installation, and verify state emissions requirements for CARB-regulated replacement parts. This converter does not include an oxygen sensor port location.

Quality Assurance

Walker designs, tests, and validates CalCat converters to meet CARB standards and deliver OE-style fitment for the listed Chevrolet applications. Part number 84178 is intended for regulated emissions replacement service where CARB certification is required.

This part fits 5 vehicles
Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
YearMakeModelLitersCylindersPositionNotes
2015ChevroletImpala2.5LL4FrontCARB Executive Order D-182-72; Engine Family Number (EFN) FGMXV02.5001; Legal for sale and use in California and other states requiring CARB-compliant replacement converters. Consult the aftermarket converter regulations in your state for details.; Exhaust Gasket is Recommended; Additional part(s) needed to complete installation - 31616 and 31532; Direct Fit Type; CalCat
2015ChevroletMalibu2.5LL4FrontCARB Executive Order D-182-72; Engine Family Number (EFN) FGMXV02.5001; Legal for sale and use in California and other states requiring CARB-compliant replacement converters. Consult the aftermarket converter regulations in your state for details.; Exhaust Gasket is Recommended; Additional part(s) needed to complete installation - 31616 and 31532; Direct Fit Type; CalCat
2014ChevroletImpala2.5LL4FrontCARB Executive Order D-182-72; Engine Family Number (EFN) EGMXV02.5001; Legal for sale and use in California and other states requiring CARB-compliant replacement converters. Consult the aftermarket converter regulations in your state for details.; Exhaust Gasket is Recommended; Additional part(s) needed to complete installation - 31616 and 31532; Direct Fit Type; CalCat
2014ChevroletMalibu2.5LL4FrontCARB Executive Order D-182-72; Engine Family Number (EFN) EGMXV02.5001; Legal for sale and use in California and other states requiring CARB-compliant replacement converters. Consult the aftermarket converter regulations in your state for details.; Exhaust Gasket is Recommended; Additional part(s) needed to complete installation - 31616 and 31532; Direct Fit Type; CalCat
2013ChevroletMalibu2.5LL4FrontCARB Executive Order D-182-72; Engine Family Number (EFN) DGMXV02.5001; Legal for sale and use in California and other states requiring CARB-compliant replacement converters. Consult the aftermarket converter regulations in your state for details.; Exhaust Gasket is Recommended; Additional part(s) needed to complete installation - 31616 and 31532; Direct Fit Type; CalCat
Directly replaces or cross-references 1 part number
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.
551889