My son, the engineer, came up with the following (all with
225 70R15 tires):
Current 3 spd/OD 3.31:
1st 2.8
2nd 1.68
3rd 1.00
OD 0.70
60mph OD 1701rpm
65mph OD 1843rpm
70mph OD 1945rpm
75mph OD 2127rpm
700r4
1st 3.06
2nd 1.62
3rd 1.00
4th 0.70
with 3.73
60mph 4th 1918rpm
65mph 4th 2077rpm
70mph 4th 2237rpm
75mph 4th 2397rpm
with 3.90
60mph 4th 2005rpm
65mph 4th 2172rpm
70mph 4th 2339rpm
75mph 4th 2506rpm
On trips to shows we typically travel at 65 to 70 mph and am currently almost to the floor at times.
