Highest Ratio Rear on SRW F350 is 3:55???

[blenhardt]

I currently pull a 13,000 lb. fifth wheel RV trailer with a 2008 F350 SRW 6.4 with a 3:73 rear. I notice on the build and price site that the 2011 SRW with the 6.7 only comes with a 3:55 max.

Does Ford think the extra HP and Torque will make up for the lower rear end ratio or will there be a loss of pulling capability??? What do you guys think???

[Longhaultransport]

That and the six speed transmission.

[richc22a]

The transmission is the same from the 250 to the 750, I currently have a 250 w 3:55's and pull an 8k bumper pull with the 6.4 no problem, I anticipate the 6.7 with more tq/hp will not have any difficulty. There are links to Ford's Arizona "field day" with these trucks showing off elsewhere in this forum.

[1tonpower]

first gear on the new 6 speed is lower then it is on the 5 speed. thats where it making up for the gear change.

[blenhardt]

So, with the 3:55 ratio, more HP and Torque on the 6.7, and another gear on the transmission will it pull better than my 6.4??? I hope to order one next year. Why do you all think Ford is not offering the 3:73 on the SRW 6.7??

[Goose350]

For the fuel economy.

[Zytek_Fan]

They're doing the same with Dodges. 3:42 gears are now standard, 3:73s are now optional

[jmelendy]

Originally Posted by blenhardt

Why do you all think Ford is not offering the 3:73 on the SRW 6.7??

It's no longer needed.

[1tonpower]

was playing with the build it price it thing on the ford sight and there is a 3.73 op

3.31 open is standord and 3.55 and 3.73 open or limited. for somr reason you cant the E-locker with the 3.73 =\

it says the that the tow rating is only 14,ooo. for the SCSB srw350 with 6.7 and 3.73. that seems why low i

[jasonmt]

Originally Posted by 1tonpower

was playing with the build it price it thing on the ford sight and there is a 3.73 op

3.31 open is standord and 3.55 and 3.73 open or limited. for somr reason you cant the E-locker with the 3.73 =\

The 3.73 and 4.30 gears are gas or DRW diesel option not available on a diesel SRW PU:



Otherwise this handy little chart below has been shamelessly copied and pasted:
TorqueShift 5R110 (2003-2010)
3.11, 2.22, 1.55, 1.00, 0.71
w/ 3.55
11.04, 7.88, 5.50, 3.55, 2.52
w/ 3.73
11.60, 8.28, 5.78, 3.73, 2.65
w/ 4.30
13.37, 9.55, 6.67, 4.30, 3.05

TorqueShift 6R140 (2011-)
3.97, 2.32, 1.52, 1.15, 0.86, 0.67
w/ 3.31
13.14, 7.68, 5.03, 3.81, 2.85, 2.22
w/ 3.55
14.09, 8.24, 5.40, 4.08, 3.05, 2.38