how much would it cost me to change from 3.73's to 4.10's... and if i did would it hurt my gas mileage more?

 

Can't help you on the price - do some googling. But it will most certainly hurt your gas mileage. A lower (numerically higher) ratio means your engine is turning more RPM's for every revolution of the rear tires.

Think of it as a 10-speed bicycle. In first gear it's easier to pedal while climbing hills (or for a truck to pull loads) but you have to pedal like crazy even though it's easier to do so. This represents a lower (numerically higher) gear ratio.

In tenth gear, you barely have to pedal on a straightway (or for a truck to pull no load) but it's hard as hell to go up a hill. This represents a higher (numerically lower) gear ratio.

With a low gear ratio (4.10) your truck will have more starting power and torque but the engine will turn more RPM's. With a high gear ratio (3.55) your engine will turn slower but it will have to work harder to do so.

Hope my analogy is somewhat helpful (and accurate) - good luck!

 

About $650 for one axle here in Canada.You will be turning around 2300 @ 70 mph(not too bad).May see an increase in the city if you drive normal and still be able to run past the factory speed limiter.If you don't like it get bigger tires next time around.I'm about to put 410's on factory 29" tires for fun!

 

well i m bout to put 33's on it.. and my truck doesn't cut off... i don't know why i have a four wheeldrive and a 2wd and the 2wd cuts off at 117mph but the 4wd i have had up to 127mph and it didn't cut... got to scared running that fast in that truck had to back off... is that $650 with labor also, cause we would do the labor our selves...

 

Do you have the tools and equipment to properly set up a new gearset?

$650 is parts and labor.

 

no but i have two buddies who have all thats needed and said they would help... labor is the biggest part isn't it?

 

Yes, and the procedure is very exacting.

 

I have been hot on this topic for months and you can do a search on my posts using 4.10 gears. I have had numerous replies to the topic. The general consensus is that this is almost necessary in the 4.6L. A 3.73 makes a remarkable difference (I have a 3.08) and the 4.10s are what make the truck really come alive. Turning more RPMs doesn't necessarily mean less gas mileage. Your habits are what play a large factor in that. You will get up to speed much qiucker with less throttle, ergo less gas. Cruising at hwy spds the truck will stay in gear instead of down shifting on mild grades. This downshifting lends to more fuel consumption and heat generation. I have been vascilating between 3.73 and 4.10. My wife has a little protege that is immaculate but not as comfortable as the truck so we take the truck more often. This makes me question 3.73 or 4.10s becuase of the driving. My drive to work is 6.8 miles one way, on and off the freeway. If anything your city mileage will go up. Most users on tis forum with 4.10s and a 4.6 report a mileage increase. Here is a link to a good gear site. Check to see if you have an open or limited slip diff.
http://www.accuautoparts.com/

 

Malexander,go w/ the 4.10's,you'll be much happier.Several of my motorhead friends that own Mustangs installed 3.73 gears over the stock gears and were not happy w/ the way their cars ran after.I installed a set of 4.10 Richmonds based on there experience w/gears and I am very pleased w/ the way my truck runs.Its very quick out of the hole,and I still have nice power in the mid-range like when you pass on the highway w/o kicking it down into passing gear,just press the gas pedal a little closer to the floor and you go.As far as fuel economy,I honestly cant say if I use more fuel or not.I have a true dual setup w/an X pipe and Magnaflow mufflers and a Diablo tune in my truck now so I'm sure they help in the fuel economy area,I fill my truck up once a week,I alternate between the plus and premium fuels every other tank and I go all week (Sun.-Sat.) on a tank of fuel.When i installed the gears,fuel economy was not a big issue,and it hasn't turned into one.The only drawback I found is that you loose a bit @ top end w/ the gears.I tried to increase my mph by raising the rev limiter through the tuner,but I just run out of motor before gear.You wont be disappointed w/ the 4.10's.Sorry so long,but I hope this helps you on your gear choice,good luck.