I went with the 3.55's but when I race my drag radials are 275/40/17's. The shorter tire height puts my gear ratio in the 3.70 range. So I get the benefit of a slightly better ratio for around town and lower ratio at the track.

 

3.55's are plenty low for this car, unless ur on the drag strip alot...

 

I have the opinion the 3.73 s keep you shifting forever in lower gears...

Unless you do that ship shift thing.

but on a good road (road course) the upper end gear spacing works pretty dam good. mostly 4-n 5th and it pulls good from these gears.

I made sure the diff said 3.73 on it before i drove away with the 2011.
Gearing great , could use a bit more top end power though.

More braking power than any car Id driven , so it lures you into turns krap your pants fast , and shave off that speed at last second , back into the gas again ..... whew adrenaline factor with this car.


Just the gearing wouldn't be as sweet with the taller ratio IMO , i figure the car would be less responsive . But the milage should improve?

 

It depends on the tranny. The MT82 (manual) and the 6R80 (auto) are both 6spd, but they have massively different internal gears.

Primarily, the 6R80 has a VERY deep 1st gear, 4.17:1, where the MT82 has a 3.66:1 1st gear. That is why the Automatic gets really low rear gears (3.15:1 and the V6 I think gets 2.76?)

You should do some calculation:
Your 1st gear in an MT82 with 3.73 rear will have an overall ratio 13.65:1 at the line (from a dead stop). This makes it much more easier to break traction and spin out the wheels.
Your 1st gear in a 6R80 will be extremely deep with 3.73 rear: 15.55! You will really spin out those wheels!

Now, for top speed/cruising speed (therefore also max MPG):
The MT82 in 6th gear with 3.73 rear is a final ratio of ~2.42:1
The 6R80 with in 6th gear with 3.73 rear is a final ratio of ~2.28:1, close to the MT82 ratio.

So, to answer your question, if you want to go 3.73 rear gear and you have the MT82, then you can.
If you have the automatic, you might want to stay with the stock gear, unless you are planning to hit the drag strip and you really want that really deep first gear.

 

Thanks! I'm in the market for a 5.0 in the next few months and was wondering about the gears. Seeing as i'm getting an automatic and it will be a daily driver you have made my decision easy!

 

Excellent write up Jim, thanks for sharing!

 

I had the same concern but in the end bought an 11 GT with the 3.73s. While they seemed a little low at first I have come to appreciate the upper RPM range of the coyote engine and am glad I have them now.

I doubt you will be disappointed

 

You inadvertantly answered a question I've been asking for weeks! Thank you!

 

Since the car redlines at 7000...you don't have to shift from 1st to 2nd as soon as some might lead you to believe. Also, in 6th, I'm at 2100 rpm at 80mph. 5th is a blast on the highway with these gears.

 

Also, shifting from 1st to 3rd is very doable...and even comfortable...if you think your having to shift too often. Hell...this car has so much torque..you cold even start in 2nd all day long.