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No heavier towing with 3.45 ratio.
But look here to get what ratio you do have:
http://www.therangerstation.com/tech_library/axle_codes.shtml
legal towing is all about Gross Combined Weight(GCW) of the vehicle and trailer weight.
So curb weight of vehicle, driver, passengers, load in bed, trailer itself and in your case the weight of boat and ANYTHING IN THE BOAT.
So if you were to pull the truck and trailer on to a truck scale you would get the GCW.
Ford published GCWR(Gross Combined Weight Rating) for all its trucks.
And thats what the cops and insurance companies go by.
To drive on public roads you have to do so in a "legal and lawful manner" it's in you insurance policy

So if you are over the GCWR and are in an accident, doesn't have to be your fault or even a weight related accident, your insurance company can disallow any claims.
And of course the tickets for illegally driving on public roads.
GCWR is more about Stopping than Going, can the brakes stop the weight in an emergency
The above is for "may" you tow a 2,400lbs trailer
"Can" you tow it is about ability not any legal aspect.
So yes trailer hitch matters, rear axle ratio and engine size
And you "can" tow a 2,400lbs trailer, must have trailer brakes
1993 ranger 3.0l probably has GCWR of 6,000lbs
regular cab weights about 3,000lbs, extended cab 3,400lbs
Add 400lbs for people and cargo, 3,400lbs
That leaves 2,600lbs for trailer
extended cab only 2,200lbs
You need to dig up your actual GCWR for 1993 Ranger
And get actual rear axle ratio, it's important
No, Overdrive puts too much strain on transmission, but if you are on flat or slightly downhill road then up to you really.