Just curious. I have my '10 GT on order, I opted for the 3.73 gears...and that's fine with me, but I'm wondering if perhaps I should have gone with the 3.55's?

Basically, im wondering, how do the 3.73's manage highway cruising speeds? Are your RPM's through the roof and is the engine racing all the time, or is it more normal than that?

 

i have 3.90 and rpms are fine, i still dont even go into 5th gear at the track,on the highway i can 75 and be around 2500 -3000 rpms so its not bad at all

 

I have the 3.73s in my 10 GT with the 5spd and I run about 2.5k @ 80mph. The engine is so smooth and the car is so quiet you hardly even notice.

 

The difference between 3.55 and 3.73 at freeway speed would be barely noticeable. Go 3.73 and forget about the rest!

 

The 3.73s will work just fine. I run 70 - 80 on the highway every day to work and my RPMs are in the low 2K range. If your worried about mpg, I get about 25 to 26mpg on the highway and 22 to 23 mpg going to and from work. But there are very few street lights where I am in Alabama. Get the 3.73 and have fun.

 

My car came with the 3.55 rear. I can assure you I have no shortage of fun.

 

I'm not saying you can't have fun with the 3.55s. I've driven mustangs with the 3.55s and the 3.73s, I prefer the 3.73s.

 

Be happy you went with the 3.73's, especially if you plan on getting different wheels/tires in the future that could possibly be a taller tire for the rear.

I have 295/45/18's out back, and with the overall extra height over stock, my gearing is equivalent to 3.3x gears, even though I have 3.55's. I don't know the exact math involved in figuring that out nor do I feel like it, but I read that if I had 3.73's, my gearing would be close to ~3.55's (which I have now). 3.90's would = ~3.73. 4.10's = ~3.90. You get the picture.

 

The difference between 3.55 and 3.73s is about 5%.

 

3:73 with 19" wheels. I am happy with it as is. I myself wouldn't do 3:55's