The simple answer may be an 18 speed Roadranger RTLO or RTOLF -16718B good for 1,650 lb ft.
Two overdrives, 0.86 and 0.73.
One size smaller is the RTLO/RTLOF-14718B, good for 1,450 lb ft
If you only wanted 13 speeds, but the same two overdrives a 16713B is the last part of the model number.
The difference in the first part of the model numbers, RTLO or RTLOF, the "F" stands for forward shift bar housing, as in shifter closer to engine. Everything under the shift cover is the same transmission...
Might want to talk to a Roadranger salesman before spending money, because I can only guess for you, they have to stand behind the product if they recommend it. Try them direct at 1-800-826-4357
Grigg
