Alternator Woes

Had my old alternator for around 5 years. Crank seal blew and got oil on my alternator, which in turn caused it to fry the regulator(Voltage gauge jumped to 17.5V and luckily I could shut it off and coast off the roadway).
Skip a few hours, I go, attain new alternator from O'Reilly's. Install then new one and I've noticed a good difference in voltage on my dedicated voltage gauge. O'reillys swears it's the OEM replacement for a 1986 Honda Accord LXi...I'm not 100% sure though. Old alternator ALWAYS kept 13.9V at idle, with all electronics and such running and up to 14.2V when it's first cranked and very cold outside. New alternator holds 13.4 at idle with all electronics and such running. Only a few times it's been cold enough it'll throw out 13.9V until it warms up then back to 13.4V.

I'm aware 13.4V is still charging the battery, and it DOES have a 4 prong plug and not a 3 prong plug...but what is everyone elses experience. I'm thinking i may need to take it back and get another. I have a feeling something is up with this one, whether it's for an Lx or just slung together crappy...idk...what say you?

Mine does the same except under full load at hot idle it will fall under 13 V. Not saying its correct but its the Orilleys brand.

Yeah, that's probably right for a reman unit. Nobody builds anything worth buying anymore so you just get to deal with the garbage they sell. O'Reilly has been pretty good for me though.

When it comes to buying parts now, I try to buy New stuff from OE suppliers on Rock Auto. It seems like Reman electrics are especially problematic.