Jump to content

Holt R

Subscriber Members
  • Content Count

  • Joined

  • Last visited

About Holt R

  • Rank

Recent Profile Visitors

The recent visitors block is disabled and is not being shown to other users.

  1. Moses, thank you for the detailed answer. I used the RPM calculator in the link you provided. I first did the baseline calculation using stock (~33" tires) with 3.42 gears, and the Aisin's final drive of .63. The resulting RPM for 65 mph (probably the ideal cruising speed for reasons you already noted) was 1426 RPM, which seems quite low for the 6.7l Cummins. For curiosity's sake, I also tried 75 mph and got a RPM of 1645, which seems closer to the engine's peak torque sweet spot (1700 RPM). I'm guessing the FCA engineers set up the gearing to allow for 75 mph at low RPM's? Even if s
  2. I’m new to the forum but have already spent a little bit of time reading earlier articles and posts (many of them very informative). My friend and I were having a discussion on gear ratios and bigger (35”) tires, specifically for a 2015 6.7l Cummins Ram 3500 (single rear wheel) with the Aisin transmission (stock gearing of 3.42). Over the course of the discussion we had several unanswered questions about re-gearing for that truck and for bigger tires in general: Why is a numerically larger gear ratio (like 4.10) referred to as “lower” gearing while a numerically smaller ratio (like 3.4
  • Create New...