Is Re-gearing worth it?

Turtle n Peeps wrote:

RCMAN46 wrote:

jwco5.3 wrote:
Just more towing power. She really struggles to get up to speed due to the lack of power. It would also be nice when not towing. I'd like the truck to last and it seems the gearing will help remove strain from the Trans and engine... but then again the higher rpm for long periods of time may not be great on it. either.

The 07 4.6 makes peak hp at 4750 rpm and peak torque at 4000 rpm.

With the 3.55 at 4000 rpm your speed is approximately 65 mph in second gear and 36 mph in first.

With a 4.56 at 4000 rpm your speed is approximately 51 mph in second gear and 28 mph in first.

A 4.56 would be good to run on a 1/4 mile drag strip. But for normal driving and towing at speeds less than 65 mph and greater than 45 mph I doubt you will find much of an advantage with the 4.56.

Cruising at 75 without a trailer you will have a big hit on fuel economy with a 4.56.

To get what you want you need more horsepower not more gearing.

Winner, winner chicken dinner.

I have said it on here a million times. Gearing does not make horsepower.

I agree. Gearing does not make power but it can affect power delivery. Let's assume for a moment you have an infinite number of gears. The motor revs up to its HP peak at 4750 RPM and stays there as the transmission shifts. That is maximum power delivered to the wheels. If a lower rear end means you can now pull overdrive you now have one more gear available than you did before. This moves you one step closer to that ideal infinite speed transmission. In reality it may make little difference but it doesn't make it zero.

Look in the example above. The 3.55's don't even allow the engine to reach its HP peak at 65MPH but the 4.56's will at about 60.