Check for broken vacuum lines to the front axle shifter.
Yes
No, not from the factory.
The transmissions are the same. The torque converters are different.
5w30
There is no engine difference. The main difference is in suspension, and trim.
The sport package, for a 1998 Dodge 1500 RAM pickup truck, will come standard with tail light covers. The covers have a chrome finish.
26 or 35 gallons
5w30 any premium brand.
probably a vacuum system leak. Older dodge trucks had the front transaxle engage by a vacuum line. Make sure your pump is working, and that there are no leaks. Then it should engage
$1500-$2000 to suck it
I would start by checking vacuum lines
Down the transmission dipstick tube.