Should I replace just the alternator pulley or the whole alternator?
Replacing just the pulley is cheaper, but on a high-mileage vehicle near 200k miles, a new alternator is often the more reliable choice. Finding the most cost-effective option can be difficult when trying to balance DIY repair costs against long-term reliability.
What the numbers show
Counted from the threads quoted below. How we count
- The most recent one is from October 2026.
- This comes up 13.9× more often in r/AskMechanics than across the site as a whole.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
Found another way around this?
Share your steps and trade-offs so fellow engineers don't have to reinvent the wheel. No account required.
- 1Replacing just the pulley or bearing instead of the whole unitDid this help you?
- 2Removing the entire alternator to inspect or replace partsDid this help you?
- 3searching online sources for installation adviceDid this help you?
- 4starting the vehicle and letting it run to prevent battery deteriorationDid this help you?
- 5checking battery terminals and the big ground cable from the block to the frameDid this help you?
- 6Asking online mechanics forums for advice on whether to replace individual worn drive component parts vs full assembliesDid this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“Trying to figure out if I can replace the pulley myself or the whole alternator.”source ↗
“Im looking for the most cost effective solution since times aren’t the best at the moment”source ↗
“Yeah you’re right, I’m near 200k miles so a new alternator is my best bet”source ↗
“Gonna go with a new alternator tho! Thanks”source ↗
“The main purpose of this post is to see if investing into a new alternator is worth it, or if you guys think there’s another solution to my problem.”source ↗
“the truck had shut off on me on two different occasions, stopped at a stop light, and once while driving home (while driving).”source ↗
“I had noticed a humming/whining noise coming from my alternator, that wasn’t there before. And recently it had been shutting off (on its own) after about 15 minutes of idling, throwing codes P0562 & P0700”source ↗
“Having trouble with my alternator replacement.”source ↗
“Looks Like your missing the Pulley for that alternator where the belt sits”source ↗
“Rattling, banging, clunking. All the noises and I can visibly see the wear.”source ↗
Where this came up
People with this problem also raised
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