BAY 12V / CHARGING SYSTEM REGISTER
Alternator/Replacement/Cost
12V Charging System Cost Register
Bay 12V / 05Form 12V-005

New vs Remanufactured vs OEM

Four part options, four price tiers, four reliability levels. The right choice depends on vehicle age, how long you plan to keep the car, and how much warranty matters to you. Below: cost and warranty side-by-side, brand-by-brand quality ratings, and the cases where reman is the smart choice or a bad idea.
Reman saving / vs new
$100 – $300
Reading verified at battery posts
Field 05a / Decision Card

Quick Recommendation

  • Vehicle under 10 years old, plan to keep: new aftermarket from Denso, Bosch, or Motorcraft.
  • Vehicle 10+ years or budget priority: remanufactured from Denso, Bosch, or ACDelco.
  • In-warranty or certified pre-owned: new OEM at the dealer to preserve coverage.
  • Beater car, selling soon: junkyard unit if available, accept the warranty risk.
  • European luxury (BMW, Mercedes, Audi): OEM is the safe choice; aftermarket reliability is mixed.
Field 05b / Four Options

Four Options Side-by-Side

OptionPriceWarrantyLifespanBest For
New OEM$300 – $7002 – 3 yrSame as factory originalIn-warranty vehicles, premium owners
New Aftermarket$150 – $4001 – 3 yrEquivalent to factoryMost owners, best value
Remanufactured$100 – $3001 – 3 yr*About 90% of newOlder vehicles, budget priority
Used / Junkyard$50 – $15030 – 90 dayUnknown, often shortBeater cars, temporary fix

* Reman warranty period varies more than any other option. Read the specific terms before buying.

Field 05c / Brands

Brand-by-Brand Quality

BrandNew $Reman $WarrantyTierNotes
Denso$220 – $620$130 – $3102 – 3 yrTop-tierToyota, Honda, Subaru OEM supplier
Bosch$240 – $680$140 – $3402 – 3 yrTop-tierEuropean OEM, very reliable
ACDelco$200 – $560$120 – $3001 – 2 yrStrongGM OEM; excellent on Chevy/GMC
Motorcraft$220 – $590$130 – $3102 yrStrongFord OEM
Valeo$220 – $640$130 – $3202 yrStrongAudi/VW OEM
Mitsubishi$210 – $580$120 – $3002 yrSolidJapanese OEM (Mitsu, Nissan)
Remy$160 – $420$110 – $2601 – 2 yrMid-tierMass-market reman supplier
TYC$130 – $360$90 – $2301 yrBudgetCheap; expect shorter life
Duralast (AutoZone)n/a$110 – $280Lifetime to original buyerMid-tierEasy returns; quality varies by SKU
Field 05d / Reman

The Remanufacturing Process

What Gets Replaced
New bearings, new brushes, new voltage regulator, new diode pack (rectifier), often new slip rings. The wear-prone consumables are all swapped.
What Gets Reused
Aluminium housing, rotor core (with new windings if needed), stator. The structural and magnetic parts are tested and reused if within spec.
Why Quality Varies
Reman is only as good as the rebuilder. A reputable Denso or Bosch reman is held to factory spec; a no-name reman might use bargain bearings and skip the diode-pack swap.
When Reman Is a Bad Idea
Water-cooled alternators (harder to seal correctly), very high-output units (heat margins matter), and vehicles you plan to keep 5+ more years.
Field 05e / Warranty

Warranty Reference

OptionPeriodCoversWhere to Claim
New OEM2 – 3 yr / unlimited miParts only by defaultBring the part to the OEM dealer counter
New Aftermarket1 – 3 yr (varies)Parts only; some chains include labor for first yearRetailer where purchased
Remanufactured1 – 3 yr (varies widely)Parts only; lifetime tier exists at chain storesRetailer where purchased
Used / Junkyard30 – 90 dayOften parts only and very limitedYard receipt; bring the failed unit

Full warranty terms (parts vs labor, factory coverage, credit-card extensions): see warranty reference.

Field 05f / Junkyard

The Junkyard Alternator Debate

A used alternator from a self-service yard is $50 to $100, but you are buying someone else worn unit with no service history. Reasonable when: a beater car you plan to scrap within a year, you can return it within 30 days, and you can get the donor vehicle’s mileage from the yard intake card. Unreasonable when: daily driver, family vehicle, or anywhere reliability matters. The $200 saved over a quality reman is the wrong economy.

Disclaimer / This site provides general cost estimates for informational purposes only. We are not affiliated with any auto repair shop, parts manufacturer, or warranty provider. Always get multiple quotes for your specific vehicle.