Been thinking about other things that i could upgrade on my car. And gears came to mind as i see a lot of talk about them.

But do they have the same effect on the car's performance even if its a Auto trans?

Being a newb i also dont really get the gear numbers the higher it goes? what happens?

Being i bought my car used is there anyway to find out what gears are in it now? Bought it used from a dealer that got it through auction and the car was only used in a commercial so i dont see anyone doing any aftermarket mods to it that i don't know about.

 

Most likley not changed like you said. there should be a tag on the diff housing though. But to answer your question, yes. Changing the final drive will have the same affect as on a manual. The autos come with a lower rear ratio than the manuals do anyway. I personal would move up to a at least a 3.73. That's a great all around ratio that gives you allot more grunt but keeps the revs from going sky high at hwy speeds.

 

wow awesome reply thanks!

 

3.73 is probably too low gearwise (too high numerically). The 2013 GT automatics with their 3.15 axle are geared very low in 1st gear, so much that it makes them equivalent to a manual 6-speed with a 3.55 rear axle in 1st gear. A 3.31 or 3.55 rear axle may be better choice.

 

I would go 4.10 with an auto.

 

EShhhhhh... all over the board here with what i should look into getting.

For example... whats the difference between

3.73 gears and 4.10 besides it being a higher number

 

The higher the ratio the more torque multiplication. A 4.10 will accelerate harder but less top end. With that your rpms at cruising speeds wil be higher. Say at 70mph you at 1700 or so rpm now, with 3.73 or 4.10 it would put your rpms anywhere from 2000 to 2200. These Arnt exact but just to give you an idea. Personally 4.10s are a bit much for a daily driver unless it sees track duty on the regular. The 3.73 will offer a very noticeable increase in acceleration and "grunt". The 4.10s would be even more so yet will have a much more adverse affect on you mpgs. In the end its up to you and what you want out of the car. 4.10s are great for getting out of the hole but will eat you out of house and home on mpgs. IMO.

 

I couldn't agree more.
Any experience with this or just winging it? Because you obviously haven't a clue.



The fastest N/A autos run 3.31's. Enough said.

 

I really don't see 4:10's as a good choice.

You should have 3:15's so I don't think changing to 3:31's would be not be worth the money.

I think a good gear would be 3:55's.

This is all opinion though. Best thing to do is try to find someone that is geared and see if they will take you for a ride so you have a comparison.

 

Settle down there. If your trying to run the best time at a track yes. I was just saying 4.10's are more fun for DD and acceleration. I don't remember the OP stating he wanted the fastest car. Maybe I misread. Am I missing something?

 

I love the 4.56's in my '11. Had 4.10's in my '07 GT automatic and they rocked. Had 4.30's in my '03 Mach 1. Gears are, by definition, a torque multiplier. And who doesn't love the feeling of more torque?

 

The biggest thing to remember is the car will only be as fast as traction will allow. If you have 4.10's but can't hook it up on the street what good does that do you? I have an auto and like others have mentioned the first gear is very low. I don't see it hooking up well with much more gear in anything other then track conditions or with a very sticky tire

 

Wow...4.56 in your 2011? Holy crap, I have them in my 98 cobra but it spins 8500 all day long. First gear must not exist lol
OP, if your car isn't tuned. Will get a better bang for your buck that way than the cost of a gear change. And a good tune makes a night and day difference in the auto.

 

Do you guys think a 3.73 gear will be to much gear for issues with spinning tires using the stock Michelin tires for the 11 plus V6? Or would a 3:55 gear be better for less tire spin on the stock tire.

 

I think of higher gear ratios (referred to as shorter gears) as being quick. The will get your Rpms up faster and into the power band of your motor quicker.

Lower gear ratios ( referred to as tall gears) are fast, better top speed.

You trade acceleration for top speed going to higher ratios.
Higher ratios are great for drag racing but your new problem becomes traction as mentioned earlier.

I went from a 2.65 to a 3.73 in my charger. The car is way more fun to drive but turns 3000 rpm at 80 mph. Don't recall the exact gains on the strip but I think it was about .3 seconds.

It was one of the most fun mods for sure but see if you can drive or get a ride in a car that has different gearing. It also affects your gas mileage.

 

I have 3.90's in mine. The gear was already in the car when I bought it. It launches hard and it shifts smooth, but it definitely spins tires easier (especially if used in conjunction with a CAI) and it winds out really fast. It's also kind of noisy.
I will say from first hand experience, I did not really understand what different gears meant when I bought it, but I did tac it out several times before I got the feel of it.
You would also benefit from beefier rear tires, upper control arms, lower control arms and probably a pan hard bar on your rear axle. These are modifications that I still need to make, but am definitely working on.

 

I wouldnt go any lower than 410,s, in fact i would stick with 373,s.If you go steeper than 410,s your gonna wind up being very unhappy unless its a highly modded street and track car.Trust me on this.

 

I wish mine were 3.73's. The 3.90's wind up so fast lol.

 

Rmurer, I love the 4.56's in mine. Makes daily driving VERY entertaining. Skip right past the 3.55 or 3.73 choices, and go with 4.10's, 4.30's, or 4.56's and you'll be very happy - even with a mildly modified (or stock) car. Trust me on this.

 

456,s on a daily driver?Trust Brian on this,then report back after and tell us how you want to kill yourself for listening to him!!! LOL