My dad's truck has had some electrical problems of late. The volt meter on the dash started jumping around, up to 14v then down to 10v. I found the pulley tensioner sprung and replaced it, nothing changed. I tested the alt at the autoparts store and it indicated it wasn't working right, so i replaced it, nothing changed. I pulled both batteries and load tested them, both good batteries less than 6 months old. I tested volts from the post on the alt to the - terminal on the battery on passide it showed 12.64v, then tested the driversside and it read 14.50v, but the dash guage still reads 11v.

Any ideas what's going on?

The volt gauge on ny 94 does the same from time to time has well. Drive to work read about 12-14 V, on way home reads 9 or less some times. Check the same things as you with no change. I've always just thought the gauges is crapping out or loose contact, but have yet to find the loose contact if thats what it is. If and then it stops working i plan on get a new agter market one. Till then I don't worry to much about it.

I know of 2 94's that have same problem, Hope some one figures out a fix.

Sometimes this condition affects the starter solenoid, but not the starter motor.

We ran a wire back to a test voltmeter in the cab, when gage was going low, voltage to battery was 14 Volts...?????

My '94 is weird like that too, when you turn the signal flashers on, watching the voltmeter you'd think you were jumping somebodys car, it drops waaaay down.

Startup it usually shows less than 10v, but she cranks fast, and the batteries are both new, it stays low until the first time you raise engine speed, then it picks up to ~12v.

If you really want to know, a second gauge in the dash somewhere would be your best bet.

None of the Dash Gauges (exc. speedo) are really known to be accurate from the factory.

Same here on my 1994. Lets see what my cable upgrade, top mounts, and regrounding does.

TDG said it best If you really want to know, a second gauge in the dash somewhere would be your best bet. However I would like to find out why this happens. Is it just 94's?

I tested volts from the post on the alt to the - terminal on the battery on passide it showed 12.64v, then tested the driversside and it read 14.50v, but the dash guage still reads 11v.

Any ideas what's going on?

There's your problem I'd bet. Not sure way but I would look carefully at the wiring going to the pass side battery

My dad's is a '96. Would you believe it ran at 11v (on the dash) for two days then jumped to 14v and hasn't moved since. I sodered a new copper terminal on the end of the starter lead and the cranking speed is improved. That may have been some of the problem.

Yes i can believe it