Some years ago I was headed south to Needles, Ca. on reaching a stop sign into Barstow noticed when starting off that the red light for battery charging was on, I pulled off and increased revs. but the light remained the same. It was just getting dark so headed into Barstow for the night and see what it was in the morning, as the Ford pickup had 84,000 miles on it since new and was 4 years old and the same battery . I noticed a Kragen auto supplies so pulled into front and told the attendant my problem, I thought it was the battery not taking a charge, so he said he'd check it out, I asked if I needed to move the pickup, he said he'd check it right there. He came out with a wheeled piece of equipment then checked,he said the battery was OK but the alternator was not charging, so we went inside and he checked if he had a new or rebuilt one to suit my truck. He had one, then took it outside, fitted it and then checked if the battery was taking a charge, it was. He had all ready told me of the price of the alternator, so I asked for the total cost, he gave me the price of the alternator plus sales tax, I asked him for the cost of installation, he said no charge as I had bought the alternator. I felt I did owe something, so I said the battery is 4 years old and he assured me the battery was OK. I told him I was so pleased with his work I'd buy a new battery to make me feel better. I believe the cost of the alternator was around $182, later on checking that was the average cost at that time.
Some years ago I had a Dodge pickup, bought it new, bought it as a stand-by for a Masda pickup that had 145,000 miles on it, and as I worked on construction needed reliable transportation, the only part replaced was the distributor cap at 87,000 miles which I was told average for that type of ignition. Some time later I received from the Dodge dealer the usual coupons, check, battery charging system, etc, etc, each check $15, so I took it in, about one month later a friend needed a battery start so I took the cables of the battery so as the Dodge wiring was isolated, under the grease the build up of crap around the battery posts was unbelievable, the most I have ever seen, I thought they would have at least removed the battery cables for cleaning when they did the checkup. Honesty is in such short supply it seems, and money undervalued.