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oakmandan's avatar
oakmandan
Explorer
Oct 01, 2018

Changing from 3.73 to 4.10 gears

Hello all,
After towing our new Reflection 320MKS from Eastern Iowa to Estes Park Colorado and back, I need more power for the hills. I have a 2015 F-250 with the 6.2 Liter engine. I have 3.73 years. Can they be swapped out for 4.10 gears, and will it help ?
Thanks

99 Replies

  • Your truck had an option from the factory for 4.30's. You may be able to find axles in the junkyard and swap them out.
  • You’ll want to go to 4.30’s! This will let the engine work more efficiently and should give you a bit more mileage. Most including me have seen a .5mpg improvement, however that is with a 4 speed auto. Either way, I wouldn’t go to 4.10. Just not enough of an improvement. In fact some people have gone to 4.56’s and have been very happy.
  • 6 speed transmission. I generally don't pull to far from home, but camp 80 to 90 nights a season.
  • Gears will not give you more power.

    You probably have a six speed transmission so the change from a 3.73 to 4.10 will probably not gain anything except a smaller wallet.

    Your six speed most likely keeps the engine well within its power band with the 3.73.
  • romore wrote:
    Probably not enough to justify the cost.


    That's my answer. If you're not satisfied with the 3.73s I think you'll only get a marginal boost with lower gears that probably wouldn't be worth the money. I'd either stick with what you've got especially if you mostly tow more in the midwest, or if you're going to hit the Rockies regularly think about switching to an oil burner.
  • You should be OK for most of your driving.
    You didn't say what transmission!
    Big thing when you get to the mountains, is slow down and shift down.
  • 4.10 sure but if spending money I would be 4.30 minimum and have 4.56 or 4.88 on the radar.

    Need to give more details on the driving experience and general use to give a recommendation.
  • I changed from 3.73 to 4.30 gears on my chevy and only gained 5MPH on 6% grades. Gas mileage suffered when not towing because the engine was revving higher at freeway speeds so it wasn't worth the swap.