My guess that I have a starter problem, but I want to run it by.

I turn key and the starter doesn't turn at.  The battery is a month old and
reads 12.72 volts before I turn the key, and 12.04 while trying to start.
When driving 60 mph the battery reads 14.0-14.4 with nothing on, and 13.7
with the light on.
It only happens once in a while.  Sometimes if I wait a minute or two it
will start but very slowly.  This happened even with the old battery.

I was going to check the grounds to the starter, and the started itself.
The grounds from the body to the engine were replaces last year.

Any idea's to what else to check?

Thanks

Jim
85 GL