kovacsr15

Just bought a 2004 Mustang GT 4.6 , automatic , the motor is fully stock except for the cold air intake. I'm thinking of changing my stock gears to 373/410 would I gain anything? Called a few shops and was told that I was wasting my time , Any thought? I m trying to get faster acceleration w/out hesitation. For now it is not a every day driver I have a warranty on the trans/motor Any suggestions?

xx10Gt

gears make a HUGE difference. If you want pure acceleration, 410s are the way to go. if you want acceleration and still some cruising rpms on the highway go with 373s. Either way its a crazy difference over stock, i dont know why a shop would tell you that.
You dont gain horsepower by the way, it just adds to your accel..

As far as warranty, the shop would have to prove your gears caused the failure for them to have a case.

kovacsr15

thanks for the imput. this is my first Mustang and don't want to blow my bank out

xx10Gt

right... a good gear kit with the install kit AND tuner is about 600. which isnt bad for what youll get. would you install yourself or no?

Nuke

Wrong forum. You're in the 2005-2014 forum.

A lot depends on what your current "stock" gears are. On the S197's, they could have come with 3.31, 3.55 or 3.73, depending on year, model and options. Not sure about the '04's...

xx10Gt

i believe 04's came with 3.27s out rear

kovacsr15

thanks for the tip.i am thinking about taking it to lee myles or aamco for the install.do I really need a tune after the install?

xx10Gt

well if you want your speedometer to be correct then yes! any handheld tuner can do it. let us know what gears you decide on.

drewsky

the other section of the forum would help you out a little more im sure. this is 05+ years here. But I do know it will help for sure! No idea why a shop would say it wouldnt.?

dbspcl

I would be very careful as to whom you take it to, it is a bear to get all the shims in correctly and everything lined up. Also, when you do it make sure you use Royal Purple and/or some friction modifier otherwise you will get noise on slow turns.

I have 4.10's and they are fantastic - love the difference. I have a 5-speed through (1st is now granny gear lol) and I think 3.73's are probably better for your automatic.