REWARDS - Respect
This mission can only be started between 20:00 and 6:00 on the in-game clock.
Head to the blip on the radar and you'll find out that the Vagos got to the train first. Take out the 3 Vagos soldiers and then another cutscene will occur with Ballas arriving. Take out the 4 Ballas members as quickly as possible. Once all 4 are dead, hop onto the back of the train for the next segment.
Ryder will be driving his truck behind the train and you will have 90 seconds to throw 10 boxes to Ryder. Hold the L1 button to power up, then release it to throw a box towards Ryder. Experiment a bit to find the right amount of power to get the box to Ryder.
When you get the last and 10th box, you hop off the train and onto Ryder's vehicle. You now have a 3-star wanted level. Head towards the nearest Pay-n-Spray (blip on radar) and get the cops off of you. Once you do that, head back to Ryder's house to finish the mission. You get some respect.