2001 Supercrew with 5.4 4x4....a always forget to state what truck it is so i got it out of the way first.

Here lately when I have gotten into the truck to start it it will turn over very slowly and then start...not never started. So today I checked the voltage on the battery after it had sat for a few hours...it was like 13.5. I started the truck and I get 18.0 volts. I shut the truck off and it jumped down top 15 volts or so and as I sat there I could watch the volts keep froming 15 all the way down into the low 13's. I hooked up a battery charger on a slow charge and came to work I will see how it is in he morning when I get home.

Is my battery going bad or do you think I have another issue...all cables and tight and clean.


Is it possible that the battery was runined by the alternator by overcharging it. When starting the truck the volts drop to about 9 or so from 13.5 then jumps up to 18 whiler running?

 

From your discription, the alternator 'regulator' is faulty.
It has over charged the battery so much and so long the battery may have been damaged and out of electrolite level so low that capacity is way down now for starting.
18 volts is way to high. It should never be much above about 15.5 v +/- at any time.
Have the alternator tested. If faulty, I would consider a new battery along with it.
With a faulty regulator letting the alternator run flat out, you likely see your head lights brighter than normal.
Good luck.

 

I have not noticed any burnt out bulbs or them getting brighter. Do you think it could juts be the volatge regulator or would the whole alternator need replaced.

 

The regulator should be replaceable.
Depends on how long this has been going on and the age of the alternator. It's hard on the alternator brushes and commutator to run wide open like that.
It can overheat the alternator, overcharge the battery to damage, corrode terminals and cable ends etc.
Just expect to have to do more than a regulator.
Here is a short 101 on charging:
The current is forced into the battery by any difference between the battery voltage and the regulator 'reference' which is usually about 14.5 +/- depending on tolerence.
As you can see the difference between 18 and 14 or 15 is 3 to 4 volts.
The normal difference at most is about 1.5 volts just after crank starting.
The regulator being non funcitional will try to force high amperage into the battery at levels of 70 to 100 amps uncontrolled. This damages the plates and cause high water loss.
An alternator is not intended to charge at those levels for more than a short time before tapering back.
A battery's cell voltage is usually designed to be 2.17 volts per cell. At 6 cells x 2.17 = 13.02 volts.
It is permissable to charge or float at voltage levels a little higher to account for higher temperatures and leakage as well as supplying the trucks current needs.
Anything to far outside these relitive limits will present an eventual problem of some sort.

Good luck.

 

Truck is fixed. It was just the battery. I hate to admit it but the batteries in my meter were bad giving me a flase reading...I feel like and idiot!!