downshifting early to 2nd towing uphill ?

[fourfourto]

Traviling down rt 40 from tx to mn the long hills with my 4,000 camper it is holding third at 3,500 rpm's but downshifts harshly at 3,600 to 2nd gear and rpm's at 5,000 (70/75 mph) I have to slow down to 60 or even 55 to hold 3rd gear.
I noticed the early drop to 2nd before but not this bad.
My dad took same route with a honda pilot with a 4,500 camper and took the hills at 70 mph in 3rd gear at 4,000 rpm.

Is there a way the shift point can be changed ?
I cant get over 3,500 rpm without 2nd kicking in

[fourfourto]

54 lookee's no input
I got several responses from the other forumX
This forums going to $hit (this is my main forum)

Anyway All's good

I made it home 5,000 miles round trip
For most small hills on the trip I could run 65 to 70 mph no problem.(at 70 or higher it will hold third but if you hit 69.9999 it goes down to 2nd at 5,500 rpm .
the larger hills around 60 mph works
little longer hills down to 55
even longer larger hills(texas/nm rt 40) it will hold 50mph but 51 will drop down to to second at a drivable 4,000 rpm's.
Average gas for trip 11.5 MPG at 9,000 lbs total weight (300 miles unhooked with about 2 hours of idle time)
I normaly get 12 to 13 mpg on the east coast