That $600 super duty alternator upgrade was a waste on my old truck

I see everyone online swearing by those high output alternators for older diesel trucks, so I dropped $600 on a 270 amp unit for my 2001 Ford 7.3. Figured it would handle my plow lights, winch, and whatever else I threw at it. But honestly, my stock 95 amp alternator never once let me down in ten years of heavy use. The new one actually caused voltage spikes that messed with my glow plug controller last winter. I had to put the old one back on after two months of chasing electrical gremlins. Has anyone else had a similar experience where a so called upgrade made things worse instead of better?

2 comments

2 Comments

hernandez.blake18d ago

Did you ever check the voltage regulator on the new alternator? I had a similar issue with a high output unit on my 2002 7.3 and it turned out the internal regulator was set too high from the factory. I swapped in a adjustable external regulator from a local shop and set it to 14.2 volts cold. That fixed the spike problem and the glow plug controller started working normal again. Sometimes those stock regulators are just more stable for our older trucks.

henderson.vera18d ago

Man I feel your pain, that sounds like $600 worth of headaches right there. My old 12 valve ate a 250 amp alternator in about three months and left me stranded with a dead battery in a blizzard, so now I just carry a spare stock one in the toolbox. Sometimes those fancy upgrades just give you more expensive problems to fix.