How does the power compare between the 4.7 and 5.9 R/T. I have a 5.9 right now, but im realizing it just isnt too practical a truck for me. I go to school in Vermont and might have to sell the R/T in the fall in search of 4x4. I want a 4.7 and was just wondering how much power they make. I love the power of my 5.9, but its just not practical for Vermont in the winter. How much power does the 4.7 make auto vs. stick? Any help would be appriecaited.

 

i believe the 4.7 was rated at 235 hp vs. 250 for the 5.9 at the crank, however the 4.7 comes with a better automatic transmission in the 45rfe resulting in more power to the ground. all in all, a 4.7 auto is probably about the same as a 5.9 auto stock vs. stock. however, a 4.7 5 speed would result in one quick truck a little more practical too.

 

Thats good to know, because I dont really wanna give up a lot of power but I will give up just a little. Im going to look for a standard if I choose to get one in the fall, but they are hard to find. How much torque do they make? I know the R/T's stock are at 350 which is quite a bit, what about the 4.7? Any how much can you gain out of those motors with simple mods?

 

i HATE my r/t in the winter, i am all over the damn road with that thing..... then the snow melts and the pavement is nice and dry and i remember why i fell in love with it in the first place.[sm=gears.gif]

 

My 2004 4.7:
230 HP
290 Torque

The 5 speed (545RFE) has two second gears; 1 up, 1 down.

There does exist a 235HP 4.7 H.O. It was available in 2005 third gens. I don't know if DCX put it in any other trucks/SUV before 2005??

 

Yeah my R/T was a diasaster last winter. I spend more time get pulled out and stuck then driving. Im live CT, and go to school in Vermont so winter is going to be a situation for me for a while. I wanna go with a 4.7 standard if I can. If its close in power thats all I care. I just dont want a dog that wont make it up hills. So they are pretty quick trucks?

 

what do you mean by the 5 spd has two second gears?

 

Here are what I think 545RFE ratios are:
1 - 3.00:1
2 - 1.67:1 up
2 - 1.50:1 down
3 - 1.00:1
4 - 0.75:1
5 - 0.67:1

Read all about this transmission on wilkie and allpar. I sure there are posts all over this site too.
I was surprised as well. That's why I joined this site. I learn a lot from people here.

 

the 545RFE is the auto trans with the 5 gears, (still only 4 forward gears) the 45RFE doesnt have the 2 second gears. that extra second gear is supposed to help with fuel mileage with different downshifting or something.

 

Apparently, the 45RFE box can programmed into a 545RFE, giving it the the full 5 speeds (6 if you count the duel 2nd gears?). Anyone know if this an easy job? I'm guessing you need the softwear from a newer model (post 03 I think) flashed onto your existing PCM. Would be good to try although with my 3.55 gears, its not exactly screaming on the highway but if I ever get around to fitting some 4.10's or even lower it would be nice to have the extra overdrive gear that the programming provides.