Surprise Alternator Replacement
10/29/2024
The weather’s been too good lately—perfect motorcycle days—so the 4Runner’s been on a little vacation. But with rain on the way, I figured I’d better move her before the kids’ cars boxed her in. Simple enough, right?
I hop in, turn the key… nothing. Dead battery. No big deal—I’ve got my trusty jump pack for moments like this. Hooked it up, hit the button, and she fired right up like nothing ever happened. There was a bit of a weird noise, but hey, she’s been sitting a few weeks. Probably just clearing her throat. I let her idle to charge up while I went back inside.
When I came back out, something felt off. The first red flag—no puddle under the A/C drain. The second—she wasn’t running anymore. Great. My gut said “alternator,” but before dropping a few hundred bucks on a hunch, I decided to test it.
Pulled out the jumper cables, hooked up my wife’s car, and brought the 4Runner back to life. Voltage looked good at first, but when I pulled the positive cable, the multimeter dropped from 12 volts to 8 faster than my motivation on a Monday. Yeah… alternator’s toast.
Parts store had exactly one in stock—a remanufactured Ultima, a brand that doesn’t exactly scream “confidence.” But time was short, so I grabbed it anyway.
The swap was straightforward: battery out for some elbow room, loosen the belt, unbolt the tensioner, and disconnect the wiring. The old alternator looked every bit of its 25 years and 163,000 miles—honestly, I think it might’ve been factory original. Kind of sad to replace a legend with a discount parts-store special, but here we are.
Once the new one was in, I fired it up, and—smooth idle, solid voltage, no weird noises. Took it around the block, and everything checked out.
For now, she’s back in action, but I’ll admit—I don’t totally trust that new alternator. Turns out, these Ultimas have about a 20% failure rate, so I might grab a backup just in case. Oh, and while I was under the hood, I noticed my LED engine bay light switch had rusted solid. Add that to the list.
There’s always a list…