Can anyone tell me why my truck goes through alternators?

Question

I have a 96 Ford Ranger I have already replaced the alternator twice and I think it might begoing bad again. Is there something that might cause the engine to burn these things up, or maybea a electrical problem that the sops are missing?

Answer 1

Most aftermarket alternators will only last about three years or 30K miles. Don't know why but few are rebuilt as good as new. The best rebuilts I've used are the AutoZone lifetime warranty alt's.

I went through two NAPA's in 30K miles and the bearings kept failing. Lucky I wasn't in the middle of no where when it started screaming.

I've seen them catch on fire when the bearing(s) fail and someone tries to drive it in way too long after it started making noise.

I've taken new ones (rebuilds) apart before and found wires not secured properly inside. Little nuts on long "screws" just not tightened down properly. Makes the voltage jump around a little bit and who knows where the little nuts may have ended up when they finally backed themselves off the screws and fell off inside the alternator.

I never saw a decent rebuilt alternator at PepBoys. It's the companies fault for not buying a quality rebuild up front.

If you have a wiring or ground issue there are a few things to check.

1. Is the engine block properly grounded to the frame/firewall with at least one of those copper braided ground straps?

2. Does the engine stall when you disconnect the battery? Most cars with electric fuel pumps will stall.

3. Does the car stall when you pull the hot wire off the alternator? Most cars should continue to run without the alternator hooked up.

Might just be a string of crappy alternators but if it really bugs you have an electric shop look it over.

Sometimes the wire loom will wear off the wire bundles and expose the wires to metal parts and their insulation can wear through giving intermittant grounding problems that are not easy to detect unless it kills the engine while running.

I saw a Volvo that some DIY guy had flubbed up and kept going through alternators. He had a double feed coming off a battery cable. It was his ex-wifes car so he may have intentionally sabotaged it. It took us a while to figure out what he'd done.

Good Luck!

Answer 2

You have to do the adding of the total amps per hour Your truck is using.
the alternator MUST exceed the totals. plus 50% otherwise .KABOOM!!!!
You have put some accesories that are killing the alt.

OR, Your vendor is a &*^%&& and is giving You the wrong part.

Answer 3

if you and a amp running your stereo or something that pulls power all at once and you lights dim sometimes you may need a more powerful alterantor it cost a little more but look at what you have spent on replacements so far and the odds are in your favor

Answer 4

Are you replacing the starter with OEM or after-market?

Answer 5

with few words.

grounding issue.

wiring issue.

clean battery connections.

test battery.

check all wiring for rubbed out spots.