Plenty of drivers dream of keeping one car forever. One Utah owner has come close with his 2016 Mazda6 Grand Touring, which now shows 450,000 miles. Yet the repair that nearly broke him had nothing to do with the engine or transmission.
The owner, who posts as @TheEpling, bought the sedan with 45,000 miles. Since then, he has added ten times that much.
“I wasn’t sure I’d make it this far.”
A Mazda6 Transmission That Was Never Serviced
He is upfront about one choice. He has never had the transmission serviced, and he calls it more of an experiment than something to brag about. Years ago, he says, his 1998 Corolla reached 430,000 miles without a transmission service. He wanted to see whether the Mazda6 could do the same.
So far, it mostly has. Still, he stresses that he drives a lot of freeway miles and is not telling anyone to skip that service. Also, the gearbox is showing its age. About a year ago, the gear display went blank on a windy uphill climb, and the car stopped shifting until he slowed down. Restarting the car fixes it, and he suspects the transmission control module. Lately, fifth gear also slips under hard acceleration, so he drops to fourth instead.
The Battery Problem That Cost $3,326
The real headache came from i-ELOOP, Mazda’s capacitor-based energy recovery system. As he explains, it needs the correct battery and the correct alternator. If either one is wrong, the charging system can cook the alternator.
“this was the biggest car pain that I’ve ever had to deal with.”
On March 25, 2025, at 420,528 miles, the battery and alternator failed on a trip to Boise. He had the car towed to a Mazda dealer, which he does not name, and paid over $1,500. According to him, that dealer installed the wrong type of battery.
About three months later, at 434,270 miles, it happened again in Boise. This time, the warning light came on and systems shut down one by one, ending with the power steering. He says the parts warranty covered 12,000 miles, and he had just passed it.
Four Shops, Three Alternators And A Car Hauler
Next, an independent shop stayed late trying to install a new alternator, but it was the wrong part for his car. Then a second dealer kept the car for three days without anyone looking at it, he says. In the end, his father-in-law drove out with a car hauler to bring it home to Utah.
There, a dealer finally spotted the battery mix-up and installed the right one. Even then, the story was not over. A remanufactured alternator failed after three weeks, and a second one threw error codes. Finally, a genuine Mazda alternator went in, and he says it has run without trouble since August.
He did get the first dealer to refund $842.18 for parts. Even so, his grand total came to $3,326.12. Had it happened near home, he estimates it would have cost about $1,900.
“Needless to say, I’m not a big fan of the i-ELOOP system.”
What Mazda6 Shoppers Can Learn From His Car
His experience offers some simple lessons for anyone shopping for a high-mileage car with a special charging system:
- Find out whether the car uses a start-stop or energy recovery system before buying a battery.
- Ask the shop to confirm the exact battery type, not just the size.
- Keep every receipt, because a parts warranty can run out sooner than you think.
- Plan for breakdowns on long trips. Repairs far from home usually cost more.
- Treat high mileage as a sign of care, not a guarantee against expensive surprises.
Where Things Stand
Today, the Mazda6 is still on the road with the right battery and a genuine alternator. It has rock chips, worn door seals and a noisy cabin, but the interior has held up well. As for advice, his is blunt.
“If you’re looking for a Mazda 6, just avoid all the years where the i-ELOOP system was utilized.”
More from Fast Lane Only
