So when I turn the key I have power in the cab I've got headlights and fan I know the battery is not dead it's a brand new battery but it seems to only start with a jump start once started with a jump start the idle is fine everything's fine radios fine etc. But after I put the manual transmission into gear and pull away it feels severely underpowered the motor starts to bog and I have to keep it alive with the gas also ABS light comes on check gauges light comes on it's acting like again it's got a dead battery or something but it's not it also makes a repetitive beeping noise I'm at a loss please help

 

FIFY.

 

Clean battery terminals and cable ends, when you use jumper cables you are by-passing your battery terminal connections since jumper cables are clamped to the outside of your cables
Cab electrics and headlights draw may be 10amps, starter motor needs 60-75 AMPs!!!
So battery cables need to be able to pass 75amps to starter, the fact other electrics work doesn't mean battery is OK, it just means it has "some" connection and at least 10amps of power left in it

I would get a Volt meter and do some tests

Key off
Battery volts should be 12.3v to 12.8volt
12.8v is a New battery
12.5v is 3 year old battery
12.3v is a 5/6 year old battery and time to change it

12.2v or less is a dead or bad battery

Now test ground, put volt meters Red probe on Battery Positive, and Black probe on alternator's Metal case
Should see EXACTLY the same volts as when testing battery, if not check or replace negative battery cables

Test alternator wires
On the back of alternator will be a stud/nut connection with 1 or 2 wires, put Red probe on that stud and black probe on alternators metal case, should see battery volts exactly
If not then Fusible link is bad/blown

Unplug the 3 wire connector on back of alternator(voltage regulator)
Test the yellow wire, with red probe, black probe on alternators case, should see battery volts
If not fuse or fusible link is blown, depends on year

Test light green wire that same way, should be 0volts
Turn on key
re-test green wire, should now see 12volt, can be slightly less than Battery Volts, but only by 0.1v
green wire is the ON/OFF switch for alternator, also Battery Light wire
If no volts with key on, then need the year of Ranger to tell you where to look

Test those 3 wires and if all test OK then your vehicles charging system wires are OK


Start engine, jump it, then remove jumper cables
Test battery voltage again
Should be 2volts higher than with key off, 14.3 to 14.8volts, if so alternator is working, if not alternator is NOT working, replace alternator because wiring is OK so can only be a bad alternator

Just as a heads up
A failing battery can ruin an alternator
A failing alternator can ruin a battery
So it is not uncommon to have to replace both battery and alternator at the same time
To avoid this issue its good to test your system once a year or anytime you see odd issues with any electrics, i.e. dimmer lights at idle(no not normal, lol) or higher or lower volts on dash Volt gauge, or flickering Battery Light

The battery in any vehicle is ONLY USED to start the engine, a "12v" battery's max voltage is 13.0v, "working" alternator's minimum voltage is 13.5volts
So when engine/alternator is running NO VOLTAGE comes from the battery, alternator is supplying ALL the voltage for the whole vehicle, and a bit more to keep battery charged up for the next Start Up
So any time engine is running if you test battery voltage you should see above 13.5v and below 14.9v, above 15v will "cook" a "12v" battery, ruin it