Just replaced the alternator and battery on thiis car with an OEM remanufactured alternator and brand new battery. They tested car one month later and say alternator has a ripple - but they say all have ripples. Should I be worried about this or should I have them replace it with another remanufactured unit?
Yes, ripple is normal, but the question is how much? You will get REAL high ripple from a home battery charger. DC generators are three-phase units and as a result, ripple is very low, until one of the six internal diodes becomes shorted, then ripple goes very high and can cause radio noise interference, and illusive engine running problems. That also reduces the generator's maximum output to exactly one third of its rated current capacity which is not enough to run the entire electrical system under all conditions.