Future Superduty Transmissions

[MGolden]

It looks like Dodge will be using an 8 speed automatic in their trucks in the 2012 model year. Does anyone know if Ford will be looking to upgrade the 6 speed in the near future?

Just curious.......

[atvman]

With 800lb-ft of torque, are more gears really necessary?

[akirby]

With 800lb-ft of torque, are more gears really necessary?

 

Only if you need 4 overdrives.........

[MGolden]

Only if you need 4 overdrives.........

 

I dont think more are necessary but I also dont think 800ft-lb is "necessary"

 

Can anyone tell me what the 65-70 mph cruise RPM's are on the new trucks?

[jpvbs]

I think the best reason to have 8 speeds is because the other guy only has 6. There probably isn't a huge gain in performance or mpg by going to 8, but Ford may have to just to look like they are keeping up.

[Edstock]

8 speeds may have crossed into the point of diminishing returns, with respect of increased component cost, and possibly the increased time spent shifting vs any gains in mpg or performance. Especially when it's the bottom-of-the-line, torque-deficient budget sleds that really need the extra gears, but are saddled with fewer. I can't wait for Mercedes or some outfit to offer a 9-speed.

Edited August 3, 2010 by Edstock

[MY93SHO]

I'd be REALLY surprised to see this transmission in the HD trucks.

 

So far it's been shown in the next Charger, I don't see it being used past the Ram1500.

 

This trans is used in euorpean luxury cars not behind a Cummins being asked to pull 24,000 lbs.

[Ron W.]

Can anyone tell me what the 65-70 mph cruise RPM's are on the new trucks?

 

 

Would vary depending on tire size and axle/gear ratio.

Edited August 3, 2010 by Ron W.

[lfeg]

With the escallation in torque anf HP recently, maybe a 10 speed autoshift from a class 8 truck?

[Deanh]

I'm waiting for someone to come up with a two speed differential....with all the electronics running vehicles and Transmissions lately, how hard would it be to have a transmission and electronic Diff talk to one another and VOILA...a plthora of 12 speeds.....probably complex as hell but hey....

[akirby]

I'm waiting for someone to come up with a two speed differential....with all the electronics running vehicles and Transmissions lately, how hard would it be to have a transmission and electronic Diff talk to one another and VOILA...a plthora of 12 speeds.....probably complex as hell but hey....

 

That's essentially how you get a 8 speed transmission - you have a 4 speed unit and a 2-speed unit and together they give you 8 gears. I suspect a 8 speed DSG would be relatively easy since its already just 2 side by side 3 speeds.

 

Unless it gives a concrete advantage with fuel economy or towing I don't see it making a difference.

[packardbob]

Who's designing it for them? If Chrysler is designing it themselves I think Ford will be okay, seeing as how Chrysler can't design a transmission worth a damn. Or anything worth a damn for that matter.

[NaviCat]

Who's designing it for them? If Chrysler is designing it themselves I think Ford will be okay, seeing as how Chrysler can't design a transmission worth a damn. Or anything worth a damn for that matter.

 

Its a ZF transmission that Chrysler will license build in Kokomo. This box is already in production with several BMW models as well as the new Range Rover with the 4.4L Ford V8 diesel. Chrysler is not capable of engineering anything this advnaced themselves.

 

There's plenty out there publicly re: this new box, its an innovative design with a new gear arrangement that has less parasitic loss than a 6 speed and is lighter than the 6HP series that it replaces.

 

Driver is fuel economy...some pretty tough standards face the industry by model year 2016......

[theoldwizard]

I'm waiting for someone to come up with a two speed differential....

It was done in the 60s, I believe on a Cougar ! Not many were sold.

 

Too heavy, too expensive. It had to be shifted at a dead stop, which was fine because it was aimed at street/strip applications.

[theoldwizard]

I think the best reason to have 8 speeds is because the other guy only has 6. There probably isn't a huge gain in performance or mpg by going to 8, but Ford may have to just to look like they are keeping up.

Over 10 years ago Ford Research Labs (now Ford Research and Innovation Center) did a lot of modeling on what would be the "optimal" number of gears in an automatic transmission with a torque converter. Now a lot of thing were included in the definition of "optimal" but the 2 most important were cost and fuel economy. Their conclusion back then was that 5 speeds should be enough. More would add too much weight to the vehicle and the small increase in fuel economy would take a long time to pay back.

 

Of course after that they tried CVT and we all now what happened to that !

 

I think the reason every one seems to be using 6 speeds today, is that some one figure out how to hook multiple planet set together in a cost/size effective manner.

[akirby]

Over 10 years ago Ford Research Labs (now Ford Research and Innovation Center) did a lot of modeling on what would be the "optimal" number of gears in an automatic transmission with a torque converter. Now a lot of thing were included in the definition of "optimal" but the 2 most important were cost and fuel economy. Their conclusion back then was that 5 speeds should be enough. More would add too much weight to the vehicle and the small increase in fuel economy would take a long time to pay back.

 

Of course after that they tried CVT and we all now what happened to that !

 

I think the reason every one seems to be using 6 speeds today, is that some one figure out how to hook multiple planet set together in a cost/size effective manner.

 

I was always impressed with the design of the 5R55, even if performance was iffy. It was just a 3 speed planetary gearset plus an overdrive which would normally yield only 4 gears. But they also use the overdrive on top of 1st gear to get 2nd gear. The only tricky shift was 2-3 since both the main gearset and the overdrive had to be shifted at the same time, otherwise it was only one or the other.

 

Does the 6F 6 speed work similarly (3 speed plus 2 speed)?

[J-150]

4 sp OD trannies can have a sour spot (as opposed to a sweet spot) where the tranny is hunting between 3 and OD.

 

 

Even now, people are mentioning this as being noticable in the 6 speeds.

 

 

Given most of these trucks will be driving in city and highway at less than70, I can see a lot of gear hunting by this 8 speed tranny.

Edited August 3, 2010 by J-150

[lfeg]

8 speeds are a bit much in a pickup. I suspect that it may be set up as a "multi-range" transmission, where certain gears are used in a "city" mode (say 2-6) and others are used in a "highway" mode (say 3-8). There also could be a "severe" mode that uses 1-5. Modes are likely to be selected and managed by the powertrain ECU, possibly with the option of a "tap shift" mode for the driver to select gears (subject to ECU overide).

 

Usually when you start getting above 5 discrete speeds, it is because the engine operates efficiently only in a very narrow RPM range, so you go to more and more closely spaced gears to keep it in that range. An 8 speed with a lockup torque converter could be a bear to manage unless the driver really likes to feel alot of shifting.

 

And the idea of a 2 speed rear axle is really impractical today. 4x4 / AWD would require both axles to be 2 speed, or an interlock to disable the function when both axles are driving. And it would just be more cost effective to incorporate a splitter in the transmission. Especially with an automatic, as most 2 speed rears do not shift very well with automatics except when stopped. Driver skill is very critical.

(And Dean, have you ever missed a shift with a 2 speed rear end? The usual result is just like being in neutral. Not fun, and usually requires coming to a stop to get engaged again.)

[theoldwizard]

Does the 6F 6 speed work similarly (3 speed plus 2 speed)?

The 6F is a GM design, at least the gear set. Ford uses it own valve body/solenoids and software.

 

I do believe that it works as you describe because I am pretty certain it has 3 planetary sets.

[theoldwizard]

4 sp OD trannies can have a sour spot (as opposed to a sweet spot) where the tranny is hunting between 3 and OD.

 

Even now, people are mentioning this as being noticable in the 6 speeds.

"Hunting" is a big problem in a customer's perception of transmission quality !

 

Even locking and unlocking the converter "feels" like a shift to some customers.

[battyr]

With 800lb-ft of torque, are more gears really necessary?

 

If you want to cut costs and improve efficiency, you need a much smaller engine with an 8-speed.

[atvman]

If you want to cut costs and improve efficiency, you need a much smaller engine with an 8-speed.

Much smaller as in 4.4L...

[jpvbs]

If you want to cut costs and improve efficiency, you need a much smaller engine with an 8-speed.

 

 

Maybe their logic is, "lets use this 8 speed with a ~6l diesel instead of that ~10l with the 6 speed."

[hoss96racing]

I mentioned this to a someone I know at Chrysler and they called BS... he is a reliable source and said until Chrysler turns itself around there won't be any major changes to the RAM trucks. For the foreseeable future there won't be any 8-speed tranny or any upgrades to the cummins.....