Dodge trucks had the transmission dipstick/fill tube near the passenger side manifold but Dodge stopped building trucks about 2010. Ram started using the ZF transmission in about 2013 and that transmission does not have a dipstick. There should be a label on the side of the transmission pan that tells how to check the fluid level. Very specific process to check and replace the fluid on the ZF transmission. The transmission must be level and at a certain operating temperature. The owner's manual does not show a service or level check spec. Some owners change the fluid at their own interval and others never check or change the fluid.