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Hey guys,

If all goes as planned, I'll be picking up my new 2020 F-450 this week. While I was test driving an XL they had in stock, I figured some folks might like to know the RPM's the new transmission pulls at various speeds.


Chris
 

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What axle ratio is this for? 4.10?

This would be cool to compare to all ratios.
 

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The 450 come with a 4.30 gear ratio. That’s good rpms are down about 150.


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The new 10 speed has a true 1:1 in 7th gear, and the 1st gear is so low that 3.31 gears have a better pulling ratio than 3.73 gears and the 6 speed have. The 10 Speed is a game changer for trucks, where short rear ends are no longer needed to pull, so better fuel economy can be had while still having the power to tow/haul heavy loads.

If you want to see the actual ratio comparisons, look at the 6.7 is NutZ thread I started, the video has the whiteboard with it. They compare a 6.7 with the 6 speed and 3.55 gears, and the 10 speed with the 3.31 gears, and the final drive with the 6 speed being .85 where the 10 speed is 100 (1:1), the difference is 9%. 3.02 vs 3.310
 

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The new 10 speed has a true 1:1 in 7th gear, and the 1st gear is so low that 3.31 gears have a better pulling ratio than 3.73 gears and the 6 speed have. The 10 Speed is a game changer for trucks, where short rear ends are no longer needed to pull, so better fuel economy can be had while still having the power to tow/haul heavy loads.

If you want to see the actual ratio comparisons, look at the 6.7 is NutZ thread I started, the video has the whiteboard with it. They compare a 6.7 with the 6 speed and 3.55 gears, and the 10 speed with the 3.31 gears, and the final drive with the 6 speed being .85 where the 10 speed is 100 (1:1), the difference is 9%. 3.02 vs 3.310
I've also been looking into the new 2020 10 speed transmission gear ratios versus the 2019 6 speed ratios. I haven't been looking at the F-450 rather the F-350 diesel equipped truck comparison as that is more relevant to me. I'm not sure if there's a difference between the F-450 and F-350. But I agree that you won't need anything above the 3.31 rear differential gear with the new 10 speed...unless you're towing some huge weight. First gear alone is a significant difference (4.615:1 in the 10 speed versus 3.97:1 in the 6 speed). And 10th speed (0.632:1) is, as it should be, below 6th speed (0.67:1) in the six speed transmission.
There is one mystery with the new 10 speed transmission I don't understand. That's the reverse gear ratio comparison. On the new 10 speed, with gobs of additional torque, the reverse gear ratio is -4.695:1 and it's (only) -3.12:1 on the 2019 6 speed. Is my arithmetic upside down? Doesn't a higher absolute numerical value (ratio), even if it's negative or 'reversed', translate to more wheel revolutions from the 4.695:1 than at 3.12:1? Perhaps a Forum member who understands my question would clarify this and/or offer whatever rationale there is for this apparent anomaly. Thanks.
BTW, I test drove a 2020 F-350 diesel with the 10 speed two days ago. There is a noticeable increase in power from the new diesel. Interestingly, the 10 speed jumps gears as you accelerate...like from 3rd to 5th. I didn't drive the truck long enough to experience all the various gear skipping tendencies which I expect change depending on the rate of acceleration, etc. But it was noticeable. I didn't care for that as it was happening but having thought about it since, with 10 speeds to row through it probably has to do that especially in the lower range (say gears 1 through 6) to get into the right gear for the actual road speed.
My order for a fully loaded 2020 F-350 KR diesel will be placed next week.
 

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There is one mystery with the new 10 speed transmission I don't understand. That's the reverse gear ratio comparison. On the new 10 speed, with gobs of additional torque, the reverse gear ratio is -4.695:1 and it's (only) -3.12:1 on the 2019 6 speed. Is my arithmetic upside down? Doesn't a higher absolute numerical value (ratio), even if it's negative or 'reversed', translate to more wheel revolutions from the 4.695:1 than at 3.12:1? Perhaps a Forum member who understands my question would clarify this and/or offer whatever rationale there is for this apparent anomaly. Thanks.
I think the answer is Yes...the new 10spd will allow you to back up slower given the same engine rpms. It's essentially the same as first gear, just spinning the opposite direction.
 

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On final drive, the higher the number, the fewer wheel revs, the lower the number the more revs. Probably setup that way since really short gears are no longer necessary with the 10 speed. Imagine 4.30 gears with that first/reverse ratio. The engine would be revving and you would barely be crawling.


As far as shifting goes, it is usually 1-3-5-7-8-9-10, when in Sport mode(if the SD has it) then it uses all the gears, and tow haul uses all of them. When cold it will shift 1-2-3-5-7-8-9-10. After a while you get so used to it that you think something is wrong when it uses 2 & 4.
 

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On final drive, the higher the number, the fewer wheel revs, the lower the number the more revs. Probably setup that way since really short gears are no longer necessary with the 10 speed. Imagine 4.30 gears with that first/reverse ratio. The engine would be revving and you would barely be crawling.


As far as shifting goes, it is usually 1-3-5-7-8-9-10, when in Sport mode(if the SD has it) then it uses all the gears, and tow haul uses all of them. When cold it will shift 1-2-3-5-7-8-9-10. After a while you get so used to it that you think something is wrong when it uses 2 & 4.
On final drive, the higher the number, the fewer wheel revs, the lower the number the more revs. Probably setup that way since really short gears are no longer necessary with the 10 speed. Imagine 4.30 gears with that first/reverse ratio. The engine would be revving and you would barely be crawling.


As far as shifting goes, it is usually 1-3-5-7-8-9-10, when in Sport mode(if the SD has it) then it uses all the gears, and tow haul uses all of them. When cold it will shift 1-2-3-5-7-8-9-10. After a while you get so used to it that you think something is wrong when it uses 2 & 4.
Thanks for the input ACD2. That make sense. BTW, I saw your post on the desirability of having a 2020 and Up Ford Super Duties Forum segment. I hope they do that as there's a considerable change with the drive line for the 2020 model year.
 
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