I don't know if this helps. In the FJ62 (HZ) I have 4.11s, 33s (255/85), H55.
I think I usually shift into 5th at about 40-45mph and 65mph is about 2400 RPM. With my initial turbine housing, pulling up to 85mph was easy, oil pressure and EGTs were fine, so I felt fine if I had to cruise short distances at that kind of speed or quick blasts for passing. I wouldn't drive across long distances like that, but the motor seemed happy to run there. You probably get a little more headroom in the HD-T.
The way Kevin Rowland and I have experimented with setups (we have similar trucks and drivetrains), if you keep the smaller tires then 3.7 gears could work but 33s feel better with 4.11s. We both would like the taller o/d gear that the A440 auto has over the H55, but dropping to 3.7 diff gears to give the taller overdrive effect makes it sluggish.
More than gearing, as I ran above altitudes > 10,000ft I found that having a turbo housing that brought boost on earlier to be a priority over cruising power. It might be something to think of if you're planning to travel around altitudes like the Atacama.
I think I usually shift into 5th at about 40-45mph and 65mph is about 2400 RPM. With my initial turbine housing, pulling up to 85mph was easy, oil pressure and EGTs were fine, so I felt fine if I had to cruise short distances at that kind of speed or quick blasts for passing. I wouldn't drive across long distances like that, but the motor seemed happy to run there. You probably get a little more headroom in the HD-T.
The way Kevin Rowland and I have experimented with setups (we have similar trucks and drivetrains), if you keep the smaller tires then 3.7 gears could work but 33s feel better with 4.11s. We both would like the taller o/d gear that the A440 auto has over the H55, but dropping to 3.7 diff gears to give the taller overdrive effect makes it sluggish.
More than gearing, as I ran above altitudes > 10,000ft I found that having a turbo housing that brought boost on earlier to be a priority over cruising power. It might be something to think of if you're planning to travel around altitudes like the Atacama.