Mustang changing gears qestion?

i heard if i get my gears changed in my mustang it will have better proformance note its a daily driver car i heard 4:10 gears will be best its an automatic car but im not sure will be the best kind of gears how much will it cost to have this done its a 2003 v6Mustang changing gears qestion?
You;ll not be able to drive on the freeway for any length of time.

Driving at the higher RPM all the time will kill your milage and shorten your engine life. Maintenance costs will increase since you'll need to change your oil more often.



Not a prudent thing to do....Mustang changing gears qestion?
you'll ruin a good Mustang and it still won't be as fast as a GT..
By changing the gears you will see a performance change, what you are really doing is changing the RPM that your engine runs for a given speed.

By installing 4:10 gears your driveshaft has to spin 4.10 times for every rotation of your axle / wheel.

Your Speedometer will be off, unless it's corrected

Your Gas Mileage will go down Considerably

It will rev higher on the highway, increasing engine wear, and shortening its life span.

Really not a great option for a daily driver

4:10 can be and are run on the street, but not a great daily driver set up.



I would suggest a free flowing exhaust and an Air Intake kit, if you are looking for a performance gain
I put 4.30 gears in mine the cost was around 800 and my mileage on the freeway is now 21 it was around 24 with the original 3.45 gears

You have a V-6 mine is a V-8 so you do the math but I would figure that you should get at least equal to what mine does. The RPM's are around 3000 at 85 MPH
since its a 3.8 V6, I say don't do a thing to it!!!!!!!!!! just wait to sell it and trad it in for what you want. If you absolutely HAVE to do something to it to make it faster then I would do with a cold air intake , reprogram the engine, and aftermarket headers. however i don't know of any websites that sell these parts on the V6.
Expect to pay around $700 for the parts and labor. Don't listen to the naysayers, gears are the best bang for the buck modification you can get. Gas mileage will go down a little, 1-2 MPG , but it's not a big deal. To get the speedometer and transmission to operate correctly, you can buy a tuner (about $350) or just have the car tuned at speedshop. You may also want to look into getting a Trac-loc unit for your rear axle.
Yea i did 4.10's with my 96 gt auto. My car has 160k when i bought a new rear-end and gears haven't messed anything up. At 75-80 you should be at 3000rpm's. I do recommend getting ford racing gears as if you search some forums people have trouble with gear whine from other company's and normally ford racing tends to be more quite and require less shims etc.



The thing is you have a 7.5 rear-end not an 8.8 like the v8's. So im not sure how stong that rear is. If the rpms seem too high for you just step down to 3:73's, if you were to go with 3.90's you might as well go with the 4:10's anyway.