How many miles do y'all have on your trucks, and when/if did you have to replace your alternator?

I was having trouble maintaing 70-75mph while going uphill in my 01 Screw 4x4 5.4L. Took it to the dealer and they said the alternator was only putting out 10amps.

Had to get it replaced, obviously, but the truck only has 63,000 miles on it. Is that an abnormally short life span for an alternator? What would cause it to go out prematurely?

 

Are you the original owner?

The alternator is a pretty important part and gets a lot of demand from all the electrical components on the vehicle. Adding a towing package w/electric brakes or a 2000 WATT amp/stereo combo will also put high strain on the alternator.

Then again, it could have just been bad luck...

I had an old Datsun Stanza and had to change the alternator on that thing almost every year...

 

Mine on my 97 Lariat lastet for 115,000 miles. I was happy with that.

 

I have a 1998 F-150 4x4 4.6L V-8 and just over 150,000 miles.
I think the alternator has finally given up.
Battery light is on all the time. Battery is not charging.
Anybody know of any tricks/tips to changing an alternator?
What about a brand name?
New or rebuilt?
Motorcraft?

gig 'em aggies!

 

My truck has the original alternator with almost 270,000 miles on the truck. The alternator's bearings were noisy at 160,000 miles. A local automotive electric shop changed the bearings for $20. I had intended to have them put new brushes in at 200,000, but you know how that goes. I have never got around to it.

If I ever do replace it, I'll get a Motorcraft. I'd avoid Autozone for electrical items, as I've had problems in the past.

 

I recently purchaced a '97 4x4 Lariat with 197,000 on it the previous owner replace the Alternator last year.

Alot better than my Exwifes old Poniac, I replaced the Alternator 4 times.