Auto Trans Rear End Gears

[03fridge]

I did a quick search, but I found answers for mostly modded cars. I've got a bone stock 07 with auto tranny. It's my daily driver...would an upgrade to 3.73 (v.the 3.31) rear end gears be worth the time and effort?

Thanks for your thoughts and opinions.

 

[skwerl]

Absolutely! Pretty much all cars and trucks with automatics are geared too high. I did the identical swap (3.31 to 3.73) in my 2002 F150 and it made a huge difference in performance with no decrease in mileage.

 

[retfr8flyr]

Makes it a different car, go for it.


Earl

 

[06WNDVLGT]

I would go 4.10s maybe even 4.30s. With the car being mostly stock the lower gears will be even more beneficial. How much freeway driving do you do?

 

[03fridge]

I do about 50 miles of freeway driving every day.

 

[808muscle]

I love my 4.10s......but I do no freeway driving.

 

[calebparkin3]

if you do that many highway miles, stay with the 3:73...I have an Auto and I went with 3:90 my milage took a pretty big hit. i drive about 40 highway miles a day. It doesnt bother me though im glad i went with the 3:90's i like the perfomance.

 

[06WNDVLGT]

75 miles a day on the freeway here with 4.10s and I get around 24mpg, I am also 5 speed though.

 

[GERMANSHEPERD]

4.10s for a stock car.

 

[droptop07]

I swapped from the 331 to 373 in my 07. Its has minor bolt on's and 73's made a difference. Not a daily driver, but more of a weekend cruiser. Its worth the swap, but think 410's should be considered. I did 373 in my auto car and a friend did 410's in his 5speed car, and they seem to run same RPM cruising.

I like the 73's and they did make a difference. But if I was to it over, think I would go with the 410's.

 

[06WNDVLGT]

I think my cruising rpm only changed like 300 rpm from 3.55 to 4.10s

 

[gil_t2]

The 5sp manual has a .68 5th gear and the 4:10's are FTW !!!! love mine

BUT the 5sp Auto has a .75 or .78 , 5th gear, SO I would go with 3:73's . I know some will say it is not enought difference, but it's a difference that I can feel.

Good Luck, make sure you but Ford gears, not Motive

 

[Greg Hazlett]

Suggestion before you invest in th gears and labor to install; have you had a tune installed for the automatic? If not do that first...what a difference the tune makes with the way the car shifts and performs....I almost did not install the 410's once the tune as on but had already bought the gears.

Concur with the 410's affecting mpg.

 

[stretch]

ive got 3.73s and i am changing to 3.27s.

 

[Fallenauthority]

ive got 3.73s and i am changing to 3.27s.

But your car is turbo isn't it?

 

[tigerhonaker]

The 5sp manual has a .68 5th gear and the 4:10's are FTW !!!! love mine

BUT the 5sp Auto has a .75 or .78 , 5th gear, SO I would go with 3:73's . I know some will say it is not enough difference, but it's a difference that I can feel.

Good Luck, make sure you but Ford gears, not Motive

I am getting ready to order new 3:73 gears for mine.
The 4:10 gears I now have eat FUEL !!!
Well on the interstate driving distance and it really suffers in the city.
So, pretty sure I am going back to the 3:73 gears and the reason is the difference in the 5-Speed Manual versus the 5th gear in the 5-Sp. TCI Super Street Fighter tranny.
My car is turning 2,500 RPM at 70 MPH with Cruise set.
I want it to be more streetable for long distance driving.
And (My-Opinion) is, it is not going to change the Fun Factor enough on the street that I will even notice.

You are exactly correct on getting the FRPP gears, {Not} Motive .......

Terry

 

[2014_GT]

3.73's with a Vortech. 4.10's if I were NA again.

 

[OU81]

I have an 06 auto dd w/ bolt ons & 4.10's. I drive 40 miles a day, 20 miles of interstate & 20 miles of stop & go city traffic. I have 2 regrets...not yanking the poor excuse for 3.31's out sooner & not going w/ 4.30 or 4.56's. The 3.31's even w/ typical bolt ons were just sad, pathetic, embarrasing...i can go on & on(however this is coming from a person that just got rid of a big ole truck that had a 3000 tc & 4.56's that cut 1.5 60's). The mpg on the car went from 25 highway to 22 but oh well, 22 is still better than 10(last truck: cammed, bolt on, geared & sprayed 04 hemi ram).

My 60's went from 2.05 w/ the 3.31's to 1.89 w/ the 4.10's. All racing aside thought IMO 4.10's & no less is the best choice for a dd auto. Ya barely touch the pedal in traffic & it goes.

 

[TexasBlownV8]

Absolutely do a gear change, ESPECIALLY if n/a! The car will feel like it has much more power ( same power ), and makes it a lot more fun.
Just think ahead a little, if you are even considering f/i in the future, plan for it now, a little, and do the gears only one time.
373's IMO are a good balance for an automatic, although 410's would be a little more fun.

Anything is better than the stock 331's.

 

[erat]

I went 3.90, but its a hardened gear and it will give you a headache with the wine. Big difference over the 3.31. NA I would go 4.10 if I did it again, much funner gear over a 3.73.