1997, 246,000 miles fires up great with block heater on but have been noticing the battery meter is at about 10 at starting, and then stays at about 13 when running. After shutting down right back to 10. I have one of those stock gauges that ranges from 8 to 18. Now replacing batteries is simple enough but was wondering if there is some other problem I should check. Thanks in advance for your thoughts including what battery brand you would recommend.

 

Voltage will read low after startup until the glow plugs shut off, which takes up to two minutes. What is the gauge reading after that?

Have you measured voltage with an actual voltmeter?

 

When I get in the truck gauge reads 10, goes to about 9 when the glow plugs are on and after they shut off gauge goes to 13 or even 14 and stays there while running. When I shut it off and check the gauge at 10. Have not measured with a vm but can.

 

Check it with a meter and let us know what you have. Do you know how old your batteries are?

Red

 

How old are the battery cables? especially the cross the front positive cable, there known to rot from the inside out..