Axles - Differentials | 2011-2016 Ford 6.7 Powerstroke
The 2011-2016 Powerstroke equipped F-250 and F-350 trucks feature a Dana 60 assembly up front and either a Dana 80 or 10.5" out back. The 10.5's were reserved for single rear wheel (SRW) applications, ... read more
The 2011-2016 Powerstroke equipped F-250 and F-350 trucks feature a Dana 60 assembly up front and either a Dana 80 or 10.5" out back. The 10.5's were reserved for single rear wheel (SRW) applications, where the larger 80 was used in all duallies (DRW). Starting with the 2011 models, the 10.5" option received an update from the previous models in the form of a 37 spline pinion, compared to the previously used 31 spline version. From the factory, these housings were typically stuffed with the popular 3.31 ratio, but also had options for 3.55, 3.73, or 4.10 ratios.
Over the years, these assemblies have proven themselves relatively reliable on moderately used trucks running stock, or close to stock tire size and power output. For those of us that demand substantial power increases and larger tires, there is room for improvement to improve the reliability and performance that they can afford. One of the best upgrades we can recommend for anyone that has increased tire size, is that of a ring and pinion ratio upgrade. As previously stated, most of these trucks came factory with a 3.31 ratio, designed to have a proper run out with a stock size tire (roughly 32" with the popular 275-65R-18 size). But as soon as you upgrade to a 37" or larger tire, all of a sudden your RPM vs. speed are effected, even causing a disruption of the shift pattern on automatic transmission equipped trucks.
Lets give the example of upgrading to a 37" tire. By using cross multiplication, we can determine that in order to have the same RPM vs. speed as with the factory tire size, you would want to install a 3.83 gear ratio (3.31/32*37). Unfortunately, in this scenario there is no such thing as a 3.83 ratio, but the closest would be a 3.73 that is readily available. Or, you can also opt to go with a slightly lower ratio of 4.10 that would give you a higher RPM vs. speed compared to stock, which is especially useful for those towing frequently.
Besides replacing the ring and pinion, we also offer numerous other upgrades, such as ARB Air Lockers, rebuild kits, and so much more. As always, if you have any questions about which product is right for you and your truck don't hesitate to give us a call or send us an e-mail to [email protected] and we would be happy to help.