Interesting to see the transmission specs for the new Mustang Coyote engine:
The new 6-speed manual offers a 1-1 5th gear and only 6th is an overdrive. 1st thru 4th gears are very close ratio: 1st gear is 3.66, 2nd 2.43, 3rd 1.69, 4th 1.32. The final drive is 3.31:1.
These are pretty good ratios – although don’t directly compare them to the earlier SF95 or Fox Mustangs because those cars used a tire diameter that was almost 1 and a half inches smaller.
Overall 1st gear ratio is 12.1146:1 for the 2011 Mustang GT with manual transmission.
Representative of the old cars is our 1983.5 Mustang GT with then all-new Borg-Warner T-5 transmissions. It provided a 2.95 first, and the 3.08:1 rear axle ratio provided an overall ratio of 9.086:1. While this didn’t help acceleration as much as the later 3.35 first gear update, it did allow the flexibility of a usable 1st gear. Better in traffic, and easier to downshift into 1st on an auto-x course. The later T-5 with it’s 3.35:1 update were much more awkward in this regards. Our ’83 had a transplanted 3.73 gearset, for an overall ratio of 11.0035. The 2011, with it’s much larger tires, is probably about the same overall as this was (although it will have 2000 more usable RPM!). Very nice.
Looking at the 6-speed automatic, we see a very wide ratio gearset: 1st is 4.17, 2nd is 2.34, 3rd is 1.52, and 4th is 1.14. Two overdrive ratios are provided: 5th is .87 and 6th is .69. Final drive is 3.15:1. This will be a great transmission for cruising and is the fuel economy leader.
Back to our 1983.5 Mustang: we purposefully waited until early Winter that year so that we could get the new T-5 that was introduced mid-year (the previous 4-speed was miserable). It’s an irony that now in 2011, 28 years later, we finally get 6 speeds in the mainstream car. That’s ridiculous, as a suitable, more economical, and far far stronger 6-speed transmission was offered by Borg Warner as far back as 1987. It’s taken this long for Ford to get modern transmission design into the Mustang. Any hope of a dual-clutch automated manual or 7-speed automatic is clearly all but hopeless… we do not intend to wait until 2030 (give or take) to enjoy one of these transmissions! At least we can expect a standard independent rear suspension a few years before that. Why does the Mustang always have to be so far behind the technology curve? ;-(