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myoung84 02-15-2013 11:10 AM

Gear Ratio
 
Anyone know what gear ratio will be in the 14 Hemi Overland?

SMG1 02-15-2013 11:29 AM

Re: Gear Ratio
 
3.09

myoung84 02-15-2013 11:31 AM

Re: Gear Ratio
 
Not too excited about that... I was hoping they were the 3.45s...

SMG1 02-15-2013 11:38 AM

Re: Gear Ratio
 
Yeah 3.45s, the 8-speed, and the Hemi would be nice. But according to this , the diesel and Pentastar get the 3.45s and the Hemi gets the 3.09s.

myoung84 02-15-2013 11:55 AM

Re: Gear Ratio
 
Isn't that the opposite of the 2013's?

kkreit01 02-15-2013 01:21 PM

Re: Gear Ratio
 
^ Pretty much. The current V6s have 3.07, and Hemis 3.45.

padgett 02-15-2013 04:36 PM

Re: Gear Ratio
 
Appropriate when you have the 8 speed with both a 4.71 low and a .67 top. Must be trying to squeeze every MPG out of the Hemi. Before the V6 top was just a .83 so needed the higher axle.

myoung84 02-15-2013 04:39 PM

Re: Gear Ratio
 
Makes sense I guess. I absolutely love my 4.56 gears in my Power Wagon which actually has an even lower final drive at 0.625, but only a 3.23 first gear.

padgett 02-15-2013 10:50 PM

Re: Gear Ratio
 
And don't forget the 30.6" tires or the 2000 (?) rpm stall speed all go into the "feel" (and I suspect even the Hemi usually starts in 2nd. Be hard to wind fast enough for a 14.6:1 first with 2.2 (? - no specs on torque converter) multiplication without a super light flywheel.

ColdCase 02-15-2013 11:31 PM

Re: Gear Ratio
 
2011-2013 Axle ratios:
3.45:1 - 3.0L
3.07:1 - 3.6L
3.45:1 - 5.7L
3.70:1 - 6.4L

For '14:
3.45 for V6 and EcoDiesel; 3.09 for V8.

How the new 8 speed transmission is geared makes a big difference. The 8 speed has a granny of a first gear 4.714 then 3.143 - 2.106 - 1.667 - 1.285 - direct - 0.839 - 0.667. The older V6 5 speed had a 3.59 first where the older 6 speed had a 3.00 first.

Overall first gear:
Old 10.98 V6,10.41 V8
New 16.26 V6, 14.57 V8

Overall top gear:
Old 2.54 V6, 2.32 V8
New 2.30 V6, 2.06 V8

denis4x4 02-16-2013 11:43 AM

Re: Gear Ratio
 
This is a very interesting thread regarding gear ratios. Note the Dodge Durango and T&C listings:

Is 3.42 the new 4.56? - Airstream Forums

padgett 02-16-2013 12:00 PM

Re: Gear Ratio
 
I suspect that in most driving, the start will be in second gear. The Hemi has enough torque to handle and with the lower differential ratio, the V6 2nd is close to its old first.

My question is what happens when floored ? The old C6 F*rd trans used to start in second and AFAIR had to be manually selected to start in first. Really dredeging my memory now but think there was D2, D1, and L - D2 started in second.

It may be that like the old GM "GR"ade retard gear, it must be selected. There are really a lot of games you can play with sets of planetary gears including concurrant rather than sequential gearing though the "switch pitch" TQ occasionally seen seems to have been replaced by the lockup.


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