Why is it worth replacing the alternator with a 130A alternator?

(technical article, read the abridged version even if you don't like tech😊 ) abridged version: The alternator is the device that charges the batteries in your car. Yes, it is definitely worth replacing the alternator with a more powerful one. It will charge the batteries faster, it will always have a “spare” charge, so you can confidently connect additional devices. In winter, at low temperatures this will be especially important. The alternator will replace for you any mechanic.

this is what a 130A alternator from Denso looks like (photo from DENSO offer)

version full for technical geeks 😊: Our Land Cruiser 120 was born in 2008.

We are equipped with two 100Ah batteries, which are originally charged by an alternator with a charging current of 80A. Such an alternator is sufficient if winter is not the dominant season and we do not use additional permanent power consumers such as a refrigerator.

In our case, we drive all year round on dipped headlights. In addition, we permanently have a built-in 60W compressor refrigerator, which draws about 5A. In winter, at sub-zero temperatures, the efficiency of the batteries decreases. It is estimated to be lower by 20-30%, depending on the temperature. Even at minus 10 degrees C, and constant driving on dipped headlights with the refrigerator on, charging with an 80A alternator may not be enough and the batteries will slowly drain.

technical data of the 80A alternator (photo from DENSO offer)

After replacing it with a 130A alternator, the problem is solved. Even at very low temperatures and additional devices turned on in the car, this alternator calmly suffices, all the time having a reserve in charging current.

technical data of the 80A alternator (photo from DENSO offer)

Cost and replacement. The cost of a 130A alternator, manufactured by Denso, is about 260 euros in Poland. The cost of replacement depends on the prices at a particular mechanic. Replacement time is about 60min, and the most convenient way to do it is through the right wheel bay, after removing the wheel. The new 130A alternator is slightly larger and heavier than the 80A, but it goes into place without a problem. PROS: -reserve charging current in all conditions -replaced alternator, which can make a difference in older vehicles -very significant change if installing a winch CONS: -need to incur the cost of the alternator and its replacement -all 130A alternators produce characteristic sounds at about 800 rpm/minute, at other speeds they do not occur Comparison of the two alternators at an estimated current draw of about 30A and two 100Ah batteries

Conditions	80A alternator	130A alternator
3h of driving (0°C)	Batteries full after ~2h	Batteries full after ~1h
10h of driving (0°C)	Full batteries, but less power reserve	Full batteries, more reserve
3h of driving (-10°C)	Charging very slow, possible undercharging	Batteries full after ~2h
10h of driving (-10°C)	Possible gradual discharge of batteries	Full batteries, stable operation