2015 RAM 1500 slippage

2015 ram rebel 8 speed transmission, slips between 1st and 2nd gear on start up and then gets better

The most common causes are poor maintenance to the automatic transmission. Often a transmission service which includes flushing out the old fluid and any metal shavings in the transmission resolves this issue. The role of your automatic transmission fluid is to keep the gnashing of metal-on-metal gears inside of your transmission from damaging itself due to friction. The fluid also acts as an anti-corrosion agent. There are other components inside of your transmission that could be causing these symptoms too, but your first stop is to check the fluid. Additional causes can include a clogged transmission filter, broken gears or bands, low transmission fluid or burnt fluid.