A Guide to Replacing the Alternator on Your 2000-2007 Subaru Outback
Everything you need to know before buying a new aftermarket alternator for your second or third-generation Outback.
- Verify your engine size (2.5L H4 or 3.0L H6) before ordering, as they use different alternators.
- Choosing a Denso-branded aftermarket part is often the same as buying the OEM part, ensuring quality and fit.
- The alternator is easy to access on top of the engine, making this a very feasible DIY job for most owners.
- Always replace the serpentine belt at the same time as the alternator to save time and prevent future issues.
Is Your Outback's Alternator Failing?
An alternator rarely fails without warning. For a 2000-2007 Subaru Outback, the signs are usually clear. If you notice any of these symptoms, it's time to inspect your charging system.
- Battery Warning Light: The most obvious sign is the battery-shaped light on your dashboard. This light specifically indicates a problem with the charging system, not necessarily the battery itself.
- Dim or Flickering Lights: Headlights and dashboard lights that seem dim, pulse, or get brighter when you rev the engine are a classic symptom.
- Whining or Grinding Noises: A high-pitched whine or a grinding sound coming from the front of the engine can signal failing bearings inside the alternator.
- Electrical Problems: Radio acting up, power windows moving slowly, or other weird electrical glitches can happen when the alternator isn't providing consistent power.
- Dead Battery: If your battery keeps dying, the alternator may not be recharging it properly. A quick test after a jump-start can help diagnose this: if the car dies shortly after removing the jumper cables, the alternator is the likely culprit. 🎬 Watch: A visual guide to diagnosing these common alternator symptoms.
Choosing the Right Aftermarket Alternator for Your Outback
When replacing the alternator on your Outback, you don't have to buy an expensive part from the dealer. Aftermarket parts can offer the same quality for less money, but it's important to choose a reputable brand.
OEM vs. Aftermarket Quality: The original alternator on your Subaru was likely made by Denso. This means buying a new Denso alternator from an aftermarket supplier is often the same as getting the original equipment part. Other high-quality aftermarket brands offer reliable performance and are a significant savings over dealer prices. The key is to avoid the cheapest, unbranded options which can fail prematurely.
Brand Tiers for Your Subaru
Not all brands are created equal. Here’s how they generally stack up based on owner experiences and industry reputation:
- Tier 1 (OEM or Equal): Denso. As the likely original equipment manufacturer, a new or remanufactured Denso alternator is a top choice for reliability and fitment.
- Tier 2 (Trusted Aftermarket): ACDelco, Bosch, and WAI Global. These brands have a strong reputation for quality. ACDelco and Bosch are major OEM suppliers for other carmakers, and their aftermarket parts are well-regarded. WAI is known for producing quality new units.
- Tier 3 (Value-Oriented): Remy, MPA, and BBB Industries. These brands are often remanufactured units that offer a cost-effective solution. While they can be a good value, some forum discussions report mixed experiences with brands like Remy. They are a viable option if budget is the main concern.
Common Ordering Mistakes to Avoid
The most common mistake is ordering the wrong alternator for your engine. The 2000-2007 Outback was available with a 4-cylinder (H4) or 6-cylinder (H6) engine, and they use different alternators.
- 2.5L H4 Engine: Typically uses a 90-amp alternator.
- 3.0L H6 Engine: Typically uses a more powerful 110-amp alternator. 🎬 See this walkthrough for replacing the alternator on H6 engines.
Always verify your engine size before ordering. Using a VIN to confirm fitment is the best way to guarantee you get the correct part.
Cost of Replacing a 2000-2007 Subaru Outback Alternator
The total cost depends on whether you do the work yourself or take it to a shop. The alternator on this generation of Outback is very easy to access, making it a good DIY project for those with basic tools.
| Item | Estimated Cost |
|---|---|
| New Aftermarket Alternator | $151 - $340 |
| Shop Labor | $120 - $250 |
| Total Professional Installation | $271 - $590 |
| DIY Cost (Part Only) | $151 - $340 |
While You're In There...
Since you have to remove the serpentine belt to replace the alternator, it's the perfect time to install a new one. Belts are inexpensive and replacing it now can save you from having to do the job again later. Check the belt tensioner and idler pulleys for noise or roughness while the belt is off.
Frequently Asked Questions (FAQ)
Can I install the alternator myself?
Yes. On the 2000-2007 Outback, the alternator is mounted on top of the engine and is easily accessible. The job requires basic hand tools (sockets, wrenches) and can typically be completed in 1-2 hours. Many step-by-step videos are available online for this specific vehicle.
🎬 Watch: Step-by-step replacement guide for 2.5L 4-cylinder Outback models.What's the difference between a new and a remanufactured alternator?
A new alternator is made of 100% new components. A remanufactured alternator has been completely disassembled, cleaned, and tested. Wearable parts like bearings and brushes are replaced with new components. A quality remanufactured unit from a top brand like Denso or Bosch can be just as reliable as a new one.
Were there any recalls or TSBs for the alternator on my Outback?
No. Searches of the NHTSA database and technical service bulletin (TSB) records show no specific recalls or service bulletins for alternator failure on the 2000-2007 Subaru Outback. Any recalls you may find are for much newer model years and different issues.
My battery light is still on after replacing the alternator. What's wrong?
First, ensure your battery is fully charged and healthy; a battery at the end of its life may not accept a charge from the new alternator. Second, check all connections, especially the small plug on the alternator and the main power wire. Finally, check the fuses in the main fuse box under the hood. A blown main fuse will prevent the alternator from charging the battery.
Helpful Videos
Technical Specifications
OEM Part Numbers: 23700AA37A 23700AA401 23700AA4018A 23700AA5228A 23700AA37AR1
Amperage varies by engine. The 2.5L H4 engine typically uses a 90 Amp alternator. The 3.0L H6 engine uses a 110 Amp alternator. The pulley is a 5-groove design.
We Have This Part in Stock
The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
- Subaru Outback: