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Starting to think that 6th gear ratio might be impractical for tires over 32". I've noticed the when traveling over 70mph the 5th gear requires no boost, while 6th gear is regularly pulling 5-6psi. Fuel economy seems to be identical in both gears.
I know Ford originally had a ton of problems when they tried putting overly small ecoboost engines in larger vehicle, the 1.5L in the Fusion for example. The engines were undersized to the point where they were constantly running relatively high boost just to maintain cruising speed. All that constant boost caused a ton of extra heat and wear on components, hence all the turbo/engine failures and fires.
So I'm wondering if it would be in the best interest for drivetrain longevity to stay out of 6th when doing 70 or higher. I assume 70mph is roughly where aerodynamic drag overwelms the engines available N/A torque for that rpm range.
For reference I have a BD with 285/75R17 (34"Ć11.2") with a 4.46 diff ratio. I assume that SAS Broncos are roughly equivalent seeing as the 4.7 gearing basically compenstates for the 35s.
-End rant
I know Ford originally had a ton of problems when they tried putting overly small ecoboost engines in larger vehicle, the 1.5L in the Fusion for example. The engines were undersized to the point where they were constantly running relatively high boost just to maintain cruising speed. All that constant boost caused a ton of extra heat and wear on components, hence all the turbo/engine failures and fires.
So I'm wondering if it would be in the best interest for drivetrain longevity to stay out of 6th when doing 70 or higher. I assume 70mph is roughly where aerodynamic drag overwelms the engines available N/A torque for that rpm range.
For reference I have a BD with 285/75R17 (34"Ć11.2") with a 4.46 diff ratio. I assume that SAS Broncos are roughly equivalent seeing as the 4.7 gearing basically compenstates for the 35s.
-End rant
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