Hello all

Noob here and first post.

93 Ranger Splash 4.0

Tonight my battery was dead and i had to get a jump. Truck started right away with the jump. After the jump, i put the headlights on and the truck almost died. Drove off and i noticed the battery light barley going on and off the whole drive home, when i hit above 2500 rpm's. I have never seen this before. I also noticed the voltage gauge jumping around, this also never happened before. I was wondering if it may need the alternator replaced or if i need a new battery. Thought id get opinions here first before i went and spent money. Thanks in advance for any responses!

BTW... awesome forum!

 

in my experince dead batterys you can always get jump aytime,but a bad alternotar will shut the truck off

 

Could be a combination of both.
I had a Mustang GT & the battery died one night, I got it jump started but by the time I made it home, the alternator was fried... almost literally, the alternator was hot enough to fry an egg after about 10 minutes (I think voltage regulator went bad).
Had to get a new battery & alternator (didn't have time to deal with rebuilding it).

If you have a good auto parts store nearby, see if they can test your battery charging ability and the alternator to see if it's charging & putting out at least 12.5 volts at idle. 12.5v is the minimum I'd want at idle on a stock alternator, 13v - 14v would be better.

What you need will depend on how old the battery is & how many miles that alternator has on it.

A good MAXX battery at Wal-Mart should run less than $85 if you get the biggest one that fits under the hood of a Ranger. Bigger (cranking amps) is always better.

You could probably get a rebuilt alternator for about $130 (with core return) from most auto parts stores. You'll probably only get a 95 amp alternator at most parts stores unless you get the 130 amp one from an Explorer (if they're even compatible), but for a few bucks more, you could order a high output alternator 200 amps or more for around $200 - $250.

Hope that helps,
Good luck

 

Sounds like its your alternator.And its good to also change battery at same time cause one could take out the other when it went bad.

 

If you have a multi meter, you could always check and see what the voltage is at the battery with the truck on and off, if you can see a noticable difference between when the engine is off and when running (12-14v) rev the engine to a few different rpms and turn on some things that will draw current, if you see the voltage going all over the place when its running or not putting out a fairly consistent voltage , then your answer is most likely the alternator, or if you by chance have an obnoxiously large sized power wire running into the cab somewhere in a not so safe manor, iv seen a few times people have something like that shorting to the chassis and cause the vehicle to do some crazy things.

 

problem solved:

bad battery wire connection where it was out of sight. replaced and no issues.

thanks guys for all the input.