3.73 or 4.10s for an AOD?

Foxfan88

My Grandpa has great wood.
Sep 13, 2004
2,487
4
0
Miami, Ok
????? Your opinions/ocmparison etc.
Plus how bad will these gears affect milage from the stock
2.73s?

Another big question, I need a DETAILED explanation on how to launch with an auto, like with my stock converter now and when i get a higher stall.
 
Since this is your daily driver (I'm assuming) by the gas mileage reference I would get 373's. They are a good all around gear for the track and street for your AOD.

On the launch you will need to practice. When you get a convertor your going to need some sticky tires though:)
 
I put 4:10s in my wife's '87 LX w/AOD. Smoked the overdrive band on the first test drive. I recommend installing an A+ servo in the trans if you're going with 4:10s. It gives the band alot more holding power.
 
3.73's if you don't plan on racing the car alot. the biggest reason for the loss in mileage besides the increased cruising rpm is the driver. With the new gears you'll be using the throttle alot more to play with the car. It will be so much more fun to drive that the loss in mileage isn't that big a deal.

As far as launching an auto at the track, you 'll probably be doing different things depending on the stall. For the stock stall, you'll pretty much want to just brake torque it a bit to preload the suspension and hammer the gas at the last yellow. This will change dramatically if you are running street tires. With street tires you'll probably spin them pretty well so feathering the throttle to reduce the spin will be necessary. With a higher stall, sticky tires are almost a necessity. You can flash the converter which means to just stab it from an idle which will cause it to jump up to close to its stall rating and then engage or brake torque it to the highest rpm's it will hold without moving and then go from there.

And when you run, just start in 1 and shift it to D when you get to your shift rpm's. Don't shift into Od, it will not upshift at full throttle anyways and could toast your OD band.
 
That seems to be an age old question these days,LOL...Ive had both,I currently have 410's and drive 124 miles round trip to work 5 days a week.(all highway) My only complaint is you are limited when cruising on the highway to 70-80mph..If you go any faster you really start to rev the sh@t out of the motor :notnice: If you can keep it under 2500 rpm your gas mileage wont be to bad..My converter hurt my mileage more then the gears..Again,if I can keep out of the gas pedal and keep it at 2500rpm or lower I still get 21mpg!! In May Im putting my 373's back in though,Im getting a Ken Belle :banana: 410's are a "real" FUN gear to have!! It makes everyday driving a blast :nice: But the 373's are a great gear too,,,I would say the only difference between the gears in gas mileage is about 2mpg!! You mite want to consider 390's also!!!
 
since my car is only goign to be driven on weekends and maybe a few nights a week after work I was thinking about going with 4:10's. The tranny has a 3500 stall. Do you think that will be to much for the street?
 
mricci said:
since my car is only goign to be driven on weekends and maybe a few nights a week after work I was thinking about going with 4:10's. The tranny has a 3500 stall. Do you think that will be to much for the street?
Do you have a stock cam?As far as launching,try what everyone else has told you,then try this.Bring it up to around 850-900rpm,just above idle.When the light drops nail it!!! Do you have DR's? If not you will need them or the gears and converter wont do sh@t for you..
 
Either gear will wake up the car like you won't believe. A little steeper gear will be better for an AOD so I would go with 4.10's. It also really depends on what you use the car for, highway driving you want a shorter gear.
 
I agree,both gears will really wake up your stang!! But dont be afraid of 410's for the highway,there not bad at all,,aod's have a big OD. And if a little too much revving for ya put a taller tire on in back!! I use Hoosier Quick time pro's at the track,and I cross the line at 5000rpm!! If I wasnt getting a SC I'd really consider 430's :nice: But if your into high speed driving then 373's would be a wise choice!!
 
Almost anyone I have talked to about gears says the 4.10 did not affect MPG hardly at all. Maybe a point or 2 at the most.

But the general rule is 4.10 on AOD and 3.73 on 5spd

But the overall rule is
FEAR NO GEAR!!!!
 
We just finished installing 4.10's in my buddies stang, and i will just say that it is a completely different car. I think the best part bout the gears, and i found this with my 5-spd and 3.73's is that it takes so much less throttle to get the car up to speed in everday driving. dont fear the gear!
 
I originally went from 2.73s to 4.10s in my AOD car and loved the change. I switched to 3.73s because I ran out of gear with the nitrous. I'm now switching to 3.55s and a 28" tall tire for the new combo. I would put 4.10s in an AOD car again unless I was planning to run quicker than 12.0s.
 
I have 4.10's and a 3000 stall. Im also running 17/245 street tires. You will need at least drag radials because traction doesnt exist on my car when starting out. I have to slowly press my gas to the floor to get a decent launch. My 60 foot averages at 2.2 and I average a 5.25-5.55 reaction time. Gas really sucks because I drive mostly in town, I fill my tank up every three days. But its very responsive, shifts and gets into its powerband very very quickly. I recommend 4.10's also, you will be very happy.....