I have a 250 SHO, 2013 model on a Ranger 520C. When going about 50 mph and let off the gas suddenly, the motor has some play and tilts up a couple inches. When I back it off the trailer in reverse, the reverse upward thrust tilts the motor up, like a bucking bronco. Doesn't seem like it should have that much play. Never seen a motor do that before. I have checked all the nuts and bolts.
Also, when trimming down, it makes a popping sound like the cylinder needs some lubrication. I tried WD40 and it seems to help, until it washes off.
Any thoughts?

Might have a leak in your tilt/trim system or air in there. Properly fill and purge and look for leaks.

Popping sound comes from the tips of the metal trim piston rods sliding against the stops as you trim. Keep a dab of marine grease on the tips only of the rams.

look at your motor mounts, my nephews boat did the same thing.

This is my guess. I have a 2013 SHO and just replaced the trim motor yesterday. It went out over the weekend. I had to purge air and fill it with fluid several times to get it back up to speed too. Works better than it did before now.

The popping sound is normal on a SHO. Lubricate it as mentioned above.

Thanks guys. How do you purge the air?

Trim the motor all the way up and unscrew the plastic plug on the fluid reservoir. Looking from the back, the trim motor is to the left, reservoir is to the right. If you need to fill it, you just trim up all the way and squirt fluid in until it runs out.

Thank you