Oct-01-2018 08:57 AM
Oct-08-2018 06:47 PM
4x4ord wrote:goducks10 wrote:
I very rarely see 2nd with my 6.4, 4.10 gears towing 9300 lbs in the mtns of Oregon. Only on the steepest curvy sections. Most of the time I'm cruisin in 4th with some 5th and some 3rd mixed in. Freeway is all 5th till I hit some hilly areas.
If you have 32" tires you will be running 3650 rpm in 3rd gear at 60 mph. The 6.4 Hemi makes about 290 HP at that rpm. You should be able to tow your trailer up a 6% grade at 60 mph in 3rd gear. Anything over 6% and your in 2nd ... I would say your truck/trailer combo is a pretty good match.
Oct-08-2018 05:07 PM
goducks10 wrote:
I very rarely see 2nd with my 6.4, 4.10 gears towing 9300 lbs in the mtns of Oregon. Only on the steepest curvy sections. Most of the time I'm cruisin in 4th with some 5th and some 3rd mixed in. Freeway is all 5th till I hit some hilly areas.
Oct-08-2018 04:23 PM
Oct-08-2018 04:16 PM
Oct-08-2018 03:55 PM
Oct-08-2018 05:36 AM
Oct-07-2018 09:54 PM
Oct-07-2018 08:04 PM
Oct-07-2018 06:04 PM
wnjj wrote:Huntindog wrote:4x4ord wrote:A flat power curve makes it even more impossible.garyp4951 wrote:
Yes your torque will be the same, but a higher number gearing will always give more torque.
I was at a 4x4 truck pull where they see who can pull the other one backwards, and a old 1980 GMC 2500 with 4:56 gears, and small tires was pulling new Fords, Rams, backwards while they were smoking their tires.lol
Like I said I can downshift, which provides a higher number gear ratio resulting in the engine speeding up. This yields the same torque on the rear axle because the Cummins ISX 15 liter engine has a flat power curve over a three gear range of the transmission.
Show your math
A flat power curve (i.e. same HP at the different engine RPM’s in each of the 3 gears) means the same wheel torque in all 3 gears since the road speed is the same. Same power equals same wheel torque applied at the same rate (road speed).
In order to have a truly flat power curve, the torque curve is decling inversely proportional to engine RPM. This means a downshift results in higher RPM (lower torque) which is then multiplied back up for the same wheel torque.
Oct-07-2018 04:39 PM
Oct-07-2018 04:24 PM
oakmandan wrote:
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
Oct-07-2018 02:41 PM
Huntindog wrote:4x4ord wrote:A flat power curve makes it even more impossible.garyp4951 wrote:
Yes your torque will be the same, but a higher number gearing will always give more torque.
I was at a 4x4 truck pull where they see who can pull the other one backwards, and a old 1980 GMC 2500 with 4:56 gears, and small tires was pulling new Fords, Rams, backwards while they were smoking their tires.lol
Like I said I can downshift, which provides a higher number gear ratio resulting in the engine speeding up. This yields the same torque on the rear axle because the Cummins ISX 15 liter engine has a flat power curve over a three gear range of the transmission.
Show your math
Oct-07-2018 12:37 PM
4x4ord wrote:A flat power curve makes it even more impossible.garyp4951 wrote:
Yes your torque will be the same, but a higher number gearing will always give more torque.
I was at a 4x4 truck pull where they see who can pull the other one backwards, and a old 1980 GMC 2500 with 4:56 gears, and small tires was pulling new Fords, Rams, backwards while they were smoking their tires.lol
Like I said I can downshift, which provides a higher number gear ratio resulting in the engine speeding up. This yields the same torque on the rear axle because the Cummins ISX 15 liter engine has a flat power curve over a three gear range of the transmission.
Oct-07-2018 12:35 PM
4x4ord wrote:That is impossible.
But the torque to the rear wheels is identical regardless of which of those three gears I select.