Do alternators last longer at higher rpm or at idle? Some of my friends say at higher rpm. And no rude ignorant answers thank you


Asked by Apr 07, 2014 at 01:11 PM

Question type: General

2 Answers


G-day, Personally i think they would last longer at the lowest rpms, cause it puts less strain on the bearings and the copper windings and brushes. The main component that gives out on alternators are the needle bearings. Alternators have lots of moving parts that wear out cause of dirt and temperature stress. Also good to keep any water out of them too, If you ever have to clean your engine bay.

Best Answer

Yes the higher the rpm the sooner the bearings will wear out. Contaminates like oil grease are the worst, then water try to keep them clean. The amount of heat created depends on the load, the more power you use, the more the alt has to make (up to it's maximum current output), the higher the current the hotter it gets.

Your Answer

Add photo

Related Questions

  • Why Doesn't CarGurus have an ignore button??? 26 answers

    An ignore button would be great to filter all the annoying answers from a couple of posters here, one in particular. CarGurus, please consider adding an ignore button.


  • Higher fuel consumption 2 answers

    I got my new Toyota Sienna 2 months ago and, to my surprise, the gas consumption is higher than me previous one by 40%. My previous Sienna had the same engine, everything absolytely the same but the t...

    2006 Toyota Sienna LE



  • Do brief high RPMs hurt your car? 9 answers

    My girlfriend is convinced that when I merge onto the highway, if I step on the gas and reach higher RPMs (like 3600 - 4800), that it's very bad for the car. It's only for that brief period of reachin...

    2013 Ford Fusion SE



  • How long do Subaru Legacys last? 58 answers

    What is a typical lifespan for Subaru Legacy wagons? I have a 1996 Subaru Legacy Brighton with 132,000 miles (bought it used, with 18k already on it). I've kept it maintained over the years. Two di...

    1996 Subaru Legacy 4 Dr Brighton AWD Wagon



  • 93 Cavalier runs rough but smooths out some at higher RPM 2 answers

    My 93 cavalier runs rough , my mechanic said it was 2 dead cylinders. A friend who is a mechanic told me to pull #1&4 plug wires and try to start ,it did but rough . Then I pulled #2&3 and it would ...

    1993 Chevrolet Cavalier RS


    Maintenance & Repair


Search General Questions

General Experts

#1 Tom Demyan
Tom Demyan
Reputation 47,060
Reputation 38,910
#3 tenspeed
Reputation 16,610
View All

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.