I had two cheap advance auto alternator remans die in about that same mileage on my 3rd gen. After those two died I went with a denso and haven't had any issues for the last several years and probably 50k+ miles.

Also had a cheap Chinese rebuilt starter that the previous owner put in instead of replacing the contacts in the Toyota one. That one died much sooner than it should have, opened it up and it had all sorts of corrosion in it.

I won't put anything that isn't OEM quality for electrical into any of my Toyotas after those experiences. Those parts are the only time my 3rd gen almost left me stranded. Never did leave me stranded, but got real close with those cheap parts.

I'd put a denso in your 4th gen. Or rebuild the OEM one if you still have it.