Can I push the train of 60052
I would not recommend pushing the motorized train base for extended periods of times. When you turn the motor, it will generate electricity. Unless that energy has somewhere to go, it will turn into heat. It's probably not an issue to do this a little bit for short periods of time, but I wouldn't do it a lot.

If you wish to make your train a push train, you could replace the base with another non-motorized base.