Before there can be an answer, need to know transmission type; 6 speed manual or 6 speed automatic?
If its the manual, its the clutch takeup cable. The shifter should have a button or detent to push in order to move it into Reverse. Its most likely loose.
If its the automatic, its most likely the brake sensor that must be engaged prior to shifting from Park. Driver must fully engage the foot brake prior to shifting from Park to Reverse and from Drive to Reverse. Most likely replacement of part will fix issue.
Sometimes there is a safety button or switch that must be held or pushed to allow this to go into reverse.
Sometimes it's linkaage (cheap to fix). Sometimes its the tranny ($$$$).
What would cause the 1995 Nissan Pathfinder not to go in forward or reverse?
I would just go with DIESEL and not GASOLINE
add atf. take to local oil change place have them drain and replace filter and fluid.
mostlikely the torque convertor is shot or tranny dodge trannys have lots of trouble when you put them in to reverse (only auto trannys) they tend to put such a strain on the motor that it dies from lack of fuel
Automatic or manual?
I would recommend you have it repaired.
I had a similar problem where it would shift into reverse or drive but not go immediately. Or sometimes it would drop out of gear and you'd have to rev up to get it to fall back into gear. i replaced the transmission filter and it fixed the problem.
I got VW sharan 2007 Auto Diesel cannot drive in Reverse while car cold after driveing hlf a Mile forward it fineplease help its been like this over a year
Diesel Pfingsten goes by Diesel.
Shift linkages not put in the correct spots.