Hitch and trailer questions???

I have a 2005 Colorado crew cab Z71 with the 5 cyl. I am getting a boat from a friend for free and need to spec out the wiring harness and the hitch. I don't know much about boats... or trailers, for that matter. I am very familiar with vehicles and modifications in general so I should have no problem hooking up and wiring the harnesses/hitch. But specs and tow capacities I need some assistance on for sure.

The boat I am getting is a 1989 Maxum 21 foot bowrider 125 horse outboard. I don't think the trailer has any brake assistance currently. I am going to pick up / look at the boat in 3 weeks. I will be pulling the boat approx. 20 miles into the city of Pittsburgh, PA on days of use and then back home.

My question is:
1) Will my Colorado have enough power to pull the boat? I am assuming I need a class III/IV hitch?
2) Will I need a transmission cooler?
3) Should I invest in a harness that has the correct configuration for a brake assist setup?

Aside from learning about boating and everything this summer. My only other use for the hitch will be extra space with one of those fold up hitch baskets for extra storage when camping.


Any thoughts and suggestions would be greatly appreciated.
Thanks

I have a 2005 Colorado crew cab Z71 with the 5 cyl. I am getting a boat from a friend for free and need to spec out the wiring harness and the hitch. I don't know much about boats... or trailers, for that matter. I am very familiar with vehicles and modifications in general so I should have no problem hooking up and wiring the harnesses/hitch. But specs and tow capacities I need some assistance on for sure.

The boat I am getting is a 1989 Maxum 21 foot bowrider 125 horse outboard. I don't think the trailer has any brake assistance currently. I am going to pick up / look at the boat in 3 weeks. I will be pulling the boat approx. 20 miles into the city of Pittsburgh, PA on days of use and then back home.

My question is:
1) Will my Colorado have enough power to pull the boat? I am assuming I need a class III/IV hitch?
2) Will I need a transmission cooler?
3) Should I invest in a harness that has the correct configuration for a brake assist setup?

Aside from learning about boating and everything this summer. My only other use for the hitch will be extra space with one of those fold up hitch baskets for extra storage when camping.


Any thoughts and suggestions would be greatly appreciated.
Thanks
You should hook up a proper harness as you will need trailer brakes. Get the trailer weight and check with the dealer if the truck will handle the load.