I meant a grunter in a good way...

You could pull like a transport...

There is no downfall to a 4.56 other than you "could" burn a bit more fuel...

 

oh okay,,i'm sorry i miss-understood what you meant by grunter,,i'm gonna go with the 4.56's and a custom tune,,i'll post the results after it's finished and I drive it for a little while,,thanks again for all your help!!!!!!!!!!

 

Keep in mind, those of us re-gearing our older F150s have four speed automatics while you guys have six speed autos with a shorter first gear and closer ratios.
Generally that means that you will not need to run gears as low (numerically high) as the 04-08 guys will.

 

wow,,you know what,,i never even noticed if all the guys that were re-gearing had newer model trucks or not,,did'nt think about that,,good piont brian,thanks!!!!

 

dont forget also that the 2009-2010 have 6 gears and the pre 2009's only had 4. Our first gear kills the 2008's first gear. Our second gear ratio is closer to the 2008's first gear.

Also...Ford put a 4.10 on the raptor which comes stock running 35's.

You might find this info usefull....

"The 4R70W, 4R75W, 4R70E, 4R75E, AODE all had a 2.84 first gear,
2.84 X 3.55 rear = 10.08 overall ratio
2.84 X 3.73 rear = 10.59 overall ratio
2.84 X 4.10 rear = 11.64 overall ratio
2.84 X 4.56 rear = 12.95 overall ratio

The 4R100 had a 2.71 first gear,
2.71 X 3.55 rear = 9.62 overall ratio
2.71 X 3.73 rear = 10.11 overall ratio
2.71 X 4.10 rear = 11.11 overall ratio
2.71 X 4.56 rear = 12.35 overall ratio

The new 6 speed 6R80E has a 4.17 first gear ... and a 2.34 second gear
4.17 X 3.55 rear = 14.80 overall ratio
4.17 X 3.73 rear = 15.55 overall ratio
4.17 X 4.10 rear = 17.10 overall ratio

2.34 X 3.55 rear = 8.30 overall ratio in second gear

The new 2010 Ford Truck 6R80E 6 speed transmission with it's low geared 4.17 first gear and a 3.55 geared axle is a lower overall ratio than either of the pre 2010 4 speed automatics in the F-150 even if you were to re-gear those pre 2010 trucks with a 4.56 rear axle (and front axle) gear.

Hell, second gear in this transmission is not all that far from first in the 4 speeds!

Another way to look at it is 6R80E's first gear 4.17 X 3.55 rear = 14.80 overall ratio devided by 2.84 first gear of the majority of the 4 speeds = a 5.21 rear gear that would be needed with a 4R70W, 4R75W, 4R70E, 4R75E, AODE ... to match the 6R80E in first gear pulling.

The 4R100 with it's 2.71 first gear needs a 5.46 rear gear to match it. ""

 

Okay...

What about when he gets on the highway...

What is the ratio of 4-5-6 gear on the 6 speed?

Low end it good for get up and go...

But it could still end up being a dog on the highway with out gearing up...


And everything before that final gear would be a huge bonus....


Any views on that?

 

Usually I find myself just cruising when i hit the highway. I find you dont really need the torque of a lower gearing when in 4th , 5th or 6th on the highway...and if you do...you can manually cause it to down shift using the throttle. I look at it as, 5th and 6th are like an over drive. would rather have the better mileage in the upper gears , and have the torque in the lower gears to get the tires moving . You always have the Tow/Haul mode also, which i do use on all large hills.

 

the 6 speeds have 2 overdrive gears (5 and 6) 6 being a higher gear than the final drive of the 4 speed autos. you need the same gear sets for final drive between the 4 speed and 6 speeds for highway final drives

 

Exactly...

I'd be upset if my truck was hunting through the las 2 gears plus TC lock up...

If the TC even locks up, I never noticed when I test drove one..

 

if i remember correctly under normal circumstances the 6 speed locks the torque converter in 4th gear, and when in Tow/Haul mode it locks in 2nd.

if you put it in tow/haul and let the engine coast down through the gears when it drops from 2nd to first the driveline will surge showing the TC disconnecting

in the 2011's the 6speeds now have a manual shift option in which when you switch to M the torque converter locks in all gears till you drop below 10MPH in first gear when the TC unlocks. pretty useful. the neat thing about the 6 speed is that its completely electronically controlled, there is not a valve body. the same technology is employed in the torque converter. its pretty technology packed. anything is possible with the transmission as soon as the ECM is cracked.

 

Huh...

So the converters locked a lot of the time....Thats really good..

Very interesting.

 

So.. What would be good gears for my 2010 since it's 6 speed? I have 3.55LS and only noticed a little difference with the 35's.. Should I just stick with the 3.55's?

 

Ideally.....

I suppose a 4.10....


I just think the 4.56 would be the way to go still...



Its all gunna depend on what you guys want for economy...

 

I don't see why not, as long as it gets off the line good enough for you.

 

well,,,this turned into a pretty good thread,,lots of info,,,,,i'm gonna try a custom tune first,, then go from there,,,thanks all!!!!!!!!