Thinking of 3.73 gears. Questions abound :)

Ok, my 95 GT is stock. I understand that the Diff. Gear is 2.73. I want to go to a 3.73 gear, but I am wondering a few things:

1. Obviously Mileage will decrease, for city driving I don't mind so much, but I do a lot of Hwy driving, and if I'm going at 100km/h (about 65 Miles/h) my RPM is about 1.6k. With the 3.73 what can I expect my RPM to be at?

2. I have to get my tranny rebuilt soon. I understand my 5th OD Gear is a ratio of 0.68:1. Is it possible to replace that gear with a 0:50:1 ratio, to balance out the difference on the Mileage and the RPM's? If I have to get the tranny rebuilt, I might as well try to put in that 0:50:1 OD Gear if possible.

I asked this in another thread but didn't get a reply. If anybody knows I would appreciate the input. Thanks.

I have 3.73 gears in my 96 GT, and at 80 MPH (Ususal cruising speed) my tach is around 2200-2300 RPM...AND I still get 20-22 MPG.....

I have 3.73's and I'm going to go back to 3.55's to put some drivability back in my car. I do a good amount of highway driving and after driving for along time when I turn the car off all I can hear is the hum of the engine in my ears because of the high rpm. Go with 3.55's in my opinion considering it is your everyday driver. Also you'll get more out of your gears.

I think I have the 3.08 Gears. I'm not sure 3.55 would be a difference enough to matter.

Does anyone know if it's possible to switch the OD 5th Gear to a lower ratio, like going from 0.68:1 to 0.50:1 or something along those lines?

When it comes to gears it can be a subjective opinion just like different cat-back tones. What is liveable for some is not for others.

I recommended 3.73's as the best rear gear for performance and dealable driving even for a lot of highway miles cars when it came to 5.0's/4.6 2V at my old work. Sold and installed over 30 sets in the course of a year and never had someone come back and complain about that they were too much.

Most people came back and thanked me for recommending them and how much faster they made the car feel.

So that is where my reccomendations stands but still I say it is subjective.

Ford still had 2.73's and/or 3.08's in 95 mustangs? Wow, i guess since the 99+ GT's have 3.55's, i assumed all SN95 GT's and up stangs had em'. While i'm still confused, my 99 base mustang does have 3.27's right?

If you really have 273's your mpg will improve with 373's unless all you do is drive on the highway. I have 390's with mixed driving. My mpg went down with the extra low gear but not too bad. My car would not be good for a regular long distance flier on the highway.

I went with 3.73 and I don't regret it at all. Very little if any change noticed if mpg. I almost went 3.55 so happy I went with 3.73 instead.

Ford still had 2.73's and/or 3.08's in 95 mustangs? Wow, i guess since the 99+ GT's have 3.55's, i assumed all SN95 GT's and up stangs had em'. While i'm still confused, my 99 base mustang does have 3.27's right?


No the 99+ GT's don't come with 3:55's, I pulled enought gears to know. .... The Mach 1's and the 03~04 Cobra's comes with 3:55's. The GT's and V6 Mustangs as well as the 99~01 Cobra's come with 3:27's.

No the 99+ GT's don't come with 3:55's, I pulled enought gears to know. .... The Mach 1's and the 03~04 Cobra's comes with 3:55's. The GT's and V6 Mustangs as well as the 99~01 Cobra's come with 3:27's.

:1:

Ok, my 95 GT is stock. I understand that the Diff. Gear is 2.73. I want to go to a 3.73 gear, but I am wondering a few things:

1. Obviously Mileage will decrease, for city driving I don't mind so much, but I do a lot of Hwy driving, and if I'm going at 100km/h (about 65 Miles/h) my RPM is about 1.6k. With the 3.73 what can I expect my RPM to be at?

2. I have to get my tranny rebuilt soon. I understand my 5th OD Gear is a ratio of 0.68:1. Is it possible to replace that gear with a 0:50:1 ratio, to balance out the difference on the Mileage and the RPM's? If I have to get the tranny rebuilt, I might as well try to put in that 0:50:1 OD Gear if possible.

I asked this in another thread but didn't get a reply. If anybody knows I would appreciate the input. Thanks.

Dude, go for it! I hung on to my 2.93's for the longest time (which in honesty I do miss the 0-80 kmh 1st gear!) but now with the 3.73's its like "WOW". I've got a 4-speed auto so yours being a 5-speed don't worry about it. I used to turn 2100-2200 RPM at 120 kmh, now its about 2500 RPM for the same speed. But before in 4th (OD) the car had no balls whatsoever, now I can actually pass people with relative ease in top gear. The increase in torque multiplication will knock your socks off especially when you shift from 1st to 2nd gear - I couldn't believe the first time I ran it out, the rear wheels squeeled so loud and long (moreso than from a standstill) and you could feel the axle hopping up and down (thats the next thing to break!).

I actually get slightly better gas mileage in the city but ya the highway is worse, although not really that bad unless I'm racing my buddy's Saleen up the 400 to the cottage LOL. If you're actually going to be stuck at 100 kph I honestly don't see mileage being a problem.

yeah I am also looking to get the 3.73 gears in my car, they seem to be a good investment from what I've heard. Curious, how hard are they to put in?

yeah I am also looking to get the 3.73 gears in my car, they seem to be a good investment from what I've heard. Curious, how hard are they to put in?

it's precision work. if you dont' know exactly what you're doing and dont' do everything right, you WILL have problems. i'm pretty hardcore about doing all my mods with my own hands, but gears are one thing i'm leaving to reputable professionals.

Wow, thanks for the input guys. So you guys are saying that my 95 GT has 3.27 diff gear stock right now?

Yeah stock they are 3.27 or 3.25. So you should see a decent improvement from the higher gears.

As for the me and my friends putting in the gears, thats gonna be a no then lol :banghead: Thankfully my sis bf is a mechanic, my friends friend is a mechanic and my next door neigher works at a car dealership :evillol: now to decide muaha

Observation today remembering this thread...96 GT with 3:73 gears, 5 speed, running Fulda 245 50 ZR16 Tires, 65 MPH = 2000 RPM, and I'm generally getting 20-22 MPG averaging 80 MPH on daily commute of 80 miles per day. I would definately change gears and enjoy the new feeling of power over what you currently have.

If your turning about 1600rpm @ 65mph with 2.73 then you will turn about 2172rpm @ 65mph with 3.73
If its possible to put a .5 OD in your transmission, then you will be truning the exact same rpm as your current setup (.68 OD and 2.73 rear).
Just put the 3.73 in and forget it.