What size gears should i use?

[GTIF]

I thinking about changing my stock gears in my 02 AOD GT, But I'm not certain on what size. I cruise at 2200rpm in overdrive @60mph and 2800 with the overdrive off. A friend of mine said 3.73 will raise the r's in o/d to about2800 and gain ample amount of power and drop considerable time in the ET aswell as gas mileage.(.40/h/w9gal. less)
This is my daily driver and weekend burner.
What do you guys think about this gear? I looked around on some of the other forums, But they were all about 5-speeds

 

[helty]

4.10s are a perfect gear for the 4.6, especially autos. i see you're pretty new to the boards. just warning you, expect a few smart ass replies about using the search option.

but 4.10s all the way. if you cant convince yourself to get them, then 3.90s at the highest. motive makes the 3.90s btw.

 

[streetstang03]

you want 4.10s

and the 99-04 autos are the 4R70W tranny. the AOD hasnt been used since 93

 

[Hornetsnest]

No secret...4.10s

You won't be disappointed...There's a reason most Autos use them

I occasionally hear Auto guys with 3.73s wishing they had tried out 4.10s...Very rarely do you here the opposite

 

[csledd]

4.10's

 

[GTIF]

I assumed thatAod ment:automatic overdrive?
ok 410's,But what about the 1/4 ,60' etc.
and street performance?
Will the tires spin more freely?

 

[03ghoststang]

if your staying N/A 4.10's all the way

 

[TweekedGT]

Just in case nobody has told you yet, get the 4.10's

 

[GTIF]

WHY the 410's guys.

 

[03ghoststang]

because the autos need to get into the power band quicker cause of the long gear ratio on the tranny they really cant use the rpms and gear shifting to keep it in the power band like a 5 speed could

 

[super302]

4.30's or bust

 

[Hornetsnest]

In other words...4.10s accelerate quicker than 3.73s...Which is a definate advantage for an auto for the reason above...If you had a 5 speed or Forced Induction, more guys would be recomending 3.73s

 

[03ghoststang]

yes but even though i have 3.73's i like them because im going supercharged in a near future so the 3.73's are perfect for FI applications and 4.10's for NA

 

[csledd]

gears are a torque multiplier.. the higher the gear the more you're multiplying your torque which means the faster your car is gonna haul ass

 

[propellerhead]

I got 4.10s in my 04 GT/auto. With firmed up shifting from a handheld tuner, I get 2nd and 3rd gear scratches. You put less strain on the transmission and you spend more time in the converter lock up gears (3rd and 4th). Driving in every gear is more fun. The only downside is my highway cruising. I used to cruise comfortable at 70-75 mph at 2100-2200 rpm. Now, I find myself cruising in the right lane, doing 55-60 in the same rpm range. I can go 75-80 and it feels great but my rpms are at 2800-3000. It feels like roadracing. It's all about smiles per mile anyway.

 

[UndeadRogue]

I thinking about changing my stock gears in my 02 AOD GT, But I'm not certain on what size. I cruise at 2200rpm in overdrive @60mph and 2800 with the overdrive off. A friend of mine said 3.73 will raise the r's in o/d to about2800 and gain ample amount of power and drop considerable time in the ET aswell as gas mileage.(.40/h/w9gal. less)
This is my daily driver and weekend burner.
What do you guys think about this gear? I looked around on some of the other forums, But they were all about 5-speeds

I have 4.10's

for a auto id recommend 4.10's
and for a 5 speed id go with 3.73's

 

[GTIF]

Them there gears sounds prety good. do any of ya all do a before and after install run at your local dragway?
You guys are convincing me much more than i thought.So, all i need to know is how are they at the track.

 

[propellerhead]

At the 1/8 mile track here, I was hitting 9.3-9.4s this past summer. I got the 4.10s and I was hitting 9.1s. I should break 8s this fall.

 

[Dark Knight GT]

4.30's or bust

I have 4.30's in my 01 GT w/ the 4r70w automatic, and I love them.

 

[jeffnoel]

Are you sure you've got stock gears GTIF? The math isn't working out with the RPMs and speed your showing above. What size tire are you running?

With stock gears and tire size at 60mph in OD you should be about 1800 rpm and 2550 rpm with OD off. The attached calculator will help you figure out what rpms you'll be running at different speeds with different size tires.

http://www.wcfords.com/stuff/calcs/EGTcalc/egtcalc.php