GM, Ford to Collaborate on Developing 10-Speed Transmissions.

Good news for all. This agreement will help GM/F which of course includes F-150 future owners.

 

Industry analysts say if engineered correctly, a nine-speed automatic transmission can raise gas mileage five to 10 percent over a six-speed model. For a Chevrolet Cruze compact, for instance, that would equal at least 2 mpg above the current estimate of 38 on the highway.

Currently, Ford and GM are behind in the transmission speed race. Several other automakers such as Chrysler and Land Rover have nine-speed coming out soon. Many automakers already have eight-speed transmissions on the road. Both GM and Ford said the joint research would help them develop the transmissions faster.

All three Detroit automakers had to cut transmission development when they ran into financial problems back in 2008, said Kevin Riddell, an engine and transmission analyst with LMC Automotive, a Detroit-area forecasting firm.

"The joint development is really going to help them out and get back onto an even playing field," he said.

 

Ford and GM jointly developed the current gen transmissions used in the sedans and crossovers. Their partnership is nothing new but to keep it going is a win for all.

Chrysler's 8 speed is currently only available behind the 3.7L V-6. Perhaps they haven't developed it to handle the torque of the Hemi.

 

Not true at all. The hemi/8-spd trucks are just starting to make it to dealers lots, at least in 4x4 configuration. 4x2 trucks are still lagging behind.

With the 8-speed the 4x4 hemi is rated at 15 city/21 highway and 17 combined.

Exactly the same rating as the 4x4 Ecoboost.

(The current 4x4 5.0L is currently rated at 14 city/19 highway and 16 combined.)

By going to an 8-spd transmission, the Hemi picked up 2 mpg in the city and 2 mpg on the highway. Wouldn't surprise me if we saw a similar boost to the 5.0L and Ecoboost when the 9 or 10 speed transmission comes into play.

A 4x4 Ecoboost rated for 17 city/23 highway sounds pretty good to me, especially if it picks up even more HP (which I'm sure is coming).

 

ya but like the six speed of today its just two over drive gears. so the addition of 3 or 4 more gears will only add more over drive right? so tell me why i would want that kind of gear pulling a load around? i think its great that ford and gm are working on better mileage in this manor but will it cost us who tow a lot? please dont flame me i am just asking.

 

In a typical transmission, the overdrive gears are the gears that have a ratio of numerically lower than 1:1.

So, if we look at Ford's 6 speed in the F150 we have the following gears:
4.17:1
2.34:1
1.52:1
1.14:1
0.86:1
0.69:1

That means you have two overdrive gears, .86 and .69.

Here's Ram's 8 speed:
4.71:1
3.14:1
2.10:1
1.67:1
1.29:1
1:1
0.84:1
0.67:1

Still two overdrive gears, .84 and .67.

So, you ask yourself, where is the big fuel economy advantage?

For city driving an 8-spd has an advantage in the spacing of its ratios. Basically, you've got more available gear ratios to choose from. That means, the engine has a better chance of staying in its peak efficiency range when it comes to torque and engine rpms. Better efficiency equals better fuel economy.

What about on the highway you ask? If they've got basically the same overdrive gears, wont they basically cruise along at roughly the same rpm assuming all else is equal?

Well, yes. Unless, you happen to use different gear ratios in the differentials.

Notice how much lower (numerically greater) the 8-speed is geared throughout most of its range, except when you start getting towards the top end where they are more or less balanced out? Thanks to that lower transmission gearing (and better spaced ratios) you can select a taller pinion gear (better highway fuel economy) and still get the same or better performance.

Basically, with the 8-speed, you can have 3.55's in the rear and actually get better performance than a 6-speed with 3.73's. All while having the same or better highway fuel economy of a six speed truck with 3.55's.

All in all, when they're done right, more transmission gears are a good thing for performance and fuel economy. There is, however, a point of diminishing returns. Going from a 4 speed to a 6 speed has a much larger impact on efficiency than going from an 8 speed to a 10 speed. Eventually you get so close to a theoretically perfect transmission that adding more gears becomes futile.

 

Thanks for the info, informative as always.