When is new transmission being released?

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But a 6 speed transmission is just outdated in that class.

I agree. And, if you look back at the development of the diesel engine use in a pickup truck here in the USA, it was painfully slow and horribly misdirected. Through the early to late 80's the diesel engine choices for pickup trucks were naturally aspirated high rpm V8 engines with three usable forward gears in the transmissions. Meanwhile, many Class 8 trucks were using high toque low rpm in-line six cylinder turbocharged engines with ten or more forward gears and had been doing so for years with good reason. So why re-invent the wheel? Why not just introduce the in-line six cylinder turbocharged engines with six or more forward gears concept right away for pickup trucks? I think that if any one of the three major pickup truck manufacturers would have jumped on this, they would have excelled in sales while boosting their reputation significantly - and, the customer would have gotten a great product right away.

In my opinion, the development of the automatic transmission placed behind the Cummins diesel engine in pickup trucks has been equally painfully slow - only offering a 4 speed automatic transmission for over 18 years? Wow! And for most of the years the converter only locked in third and fourth gear with fourth gear being a overdrive with limited torque handling capability. And, for years the transmission could not support an exhaust brake. Again, painfully slow development.

And then we bump up to the six speed automatic transmission - with two overdrive gears behind a high torque in-line six cylinder engine. So only one added gear between first gear to direct gear when comparing to the 4 speed automatic transmission. Sure, it is another improvement, but again painfully slow.

So, why not an eight or ten speed automatic transmission that would lock up in every gear (please, don't add more overdrives!) to really allow that Cummins to perform! A transmission of this nature would shine towing heavy loads up or down hills in mountainous terrain or getting a heavy load moving on a steep uphill grade. The torque limiting feature on the Cummins engine would not affect the ability of the transmission to get the truck moving because the lower gears of an 8 or 10 speed transmission would give the needed torque multiplication to easily get the job done.

At least the six speed manual transmission placed the gear ratios where needed, and it only had one overdrive. And, of course, it is gone.

Okay, I will quit now.

- John
 
You guys do realize that most Allison Transmissions behind 6 cyl Diesels in Class 6-8 applications are 4,5 and 6 speeds...that will get 80,000 lbs rolling at road speed??

Let up on the throttle just enough to prevent the downshift and let it lug.....

More gears = More complexity......

JMHO.....

My 48RE gets a load moving but it could be a whole lot better and it would be nice to to have my hand on the shifter every time towing : OD ON, OD OFF, OD ON, OD OFF, 2ND GEAR LOCK UP, 3RD, OD ON , ON OFF, 2ND GEAR, OD ON and repeat.......
 
I don't know that Allison and Class 8 trucks are often heard in the same sentence.

More gears = more versatility. One of the biggest complaints heard in here is how people wish they had a 3.73, 4.10 or 4.30 differential in their 2500

It's just gearing people and gearing is just torque mulitplication. A 4.61 1st gear combined with a 3.42 differential has a better mechanical advantage than a 4.10 diff and a 3.23 1st gear. Or even a 4.30 diff. Plus, there are a bunch of steps in between.

Not only that, the 10R140 gives you 3 (three) overdrives compared to our 2.

The 68RFE is a good transmission.... For its day.

It's time for an 88RFE or even a 98RFE. Better yet, an 89 or 99RFE, (at Chrysler, the first number is the number forward gears (6,8....) and the 2nd number is it's torque-handling ability on a scale of 2 to 9) and the the Aisin is a little bit of a dinosaur. Good/great transmisson but you better hope you never have to work on it. Plus, there's a bit of parasitic power loss because of it's size, weight and internal workings. Not knocking it, just tie for FCA to update both. If they can't, they need to get ZF to do it for them.

The other thing about Aisin is, the Japanese are notorious about not wanting to keep making spare parts once they 'sunset' something. Like generic motors, they can leave you high and dry sometimes. Unless the aftermarket picks it up.

Sorry to be long-winded
 
You guys do realize that most Allison Transmissions behind 6 cyl Diesels in Class 6-7 applications are 4,5 and 6 speeds...that will get up to 80,000 lbs rolling at road speed??

Let up on the throttle just enough to prevent the downshift and let it lug.....

More gears = More complexity......

JMHO.....


I don't have the experience you do but most of the medium duty rigs I've driven either have more gears than that or a 2 speed rear. That or the rear end is geared so low they aren't meant for the highway....I ran a couple Inter trashionals with a 5 speed trans and a single speed rear end, at 65 mph that thing was almost redlined at 2600 rpm. It sounded like it was on the verge of launching into orbit.
Same truck with a 5/2 set up was a whole nother animal. Spicer trans and gears if I remember right.
 
You are correct, I meant to say Class 6 and 7....Allison is trying to push into the Class 8 with the TC-10 offering....

Allison just stopped production of the TC10.

But your point is well-taken by me. I'm not being argumentative at all. I don't disagree with what you said about complexity, you're right. But so are the people that want a new 8, 9 or 10 speed auto in their Ram CTD.

Both sides are right, IMO.
 
Watch the TFLtruck tow test and MPG test videos. The Ram falls short on MPG by a fair bit. Best exhaust brake and best DEF MPG but fuel consumption isn’t competitive. Will a 8-10spd equate to better MPG? I believe so. Just keep engine in the most efficient RPM when towing.
 
My 48RE gets a load moving but it could be a whole lot better and it would be nice to to have my hand on the shifter every time towing : OD ON, OD OFF, OD ON, OD OFF, 2ND GEAR LOCK UP, 3RD, OD ON , ON OFF, 2ND GEAR, OD ON and repeat.......

Oh Yeah, I know that game.
Often driving it like a stick shift.
 
To me coming from the ED and a 8 spd zf, this rfe is clumsy. Hopefully reliable, that is my only concern but, it's old school


I recently drove an 8hp behind a 3500 6.4 and holy cow did it make that truck feel like a puller over the older 66rfe's. We have a 1500 with the 8HP at work, that trans has close to 100k HARD and short miles, many of them in 4 wheel drive pulling pumps through the slop. It's been flawless and drives like a dang hot rod on the hard pan...or so I've been told :D:D
 
I recently drove an 8hp behind a 3500 6.4 and holy cow did it make that truck feel like a puller over the older 66rfe's. We have a 1500 with the 8HP at work, that trans has close to 100k HARD and short miles, many of them in 4 wheel drive pulling pumps through the slop. It's been flawless and drives like a dang hot rod on the hard pan...or so I've been told :D:D
 
As I recall on the ED, the transmission was bullet proof and that was good as the little italian had issues big time. Didn't need anymore drama.The ZF is in current Rolls Royce and other high end applications.
 
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The heavy trucks aren't using automatics for the most part - they use automated manual transmissions, which have the same number of gears as clutched manuals. A 10 or 12 speed automated manual would be an amazing transmission for a diesel HD pickup, as like a handshaker, it's not limited to the sequential upshifts and downshifts of an automatic. If you only need 2, 5, 7, 9, and 10 while empty, you can do that with an AMT... without having to wait for an automatic transmission to pause and electronically "skip" the gears in between. AMTs have been in production for years - ZF AS-Tronic, Eaton Advantage, Volvo I-Shift to name a few - so Cummins and FCA... whoops, Stellantis... can get that done. Cummins certainly has experience hooking AMTs to their engines in medium and heavy trucks.
 
You guys would agree that this is the pinnacle of trailer towing goodness and all that is right with the world, correct??? If we won the Lottery this would be what we bought to tow our brand new forty foot 5 slide triple axle RV or a trailer full of horses.....??

Guess how many speeds the transmission has.......

Specs here...https://www.truckpaper.com/listings...13193/2021-freightliner-business-class-m2-106

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Who needs a lot of gears, when you have a lot of torque!

Cummins ISL Spec Engine Data
Compression Ratio 16.6:1
Horsepower 280 - 400 HP
Torque
Range 700 to 1255 ft-lbs
 
Ram absolutely needs a new transmission. Maybe source it from ZF, who makes a very good auto. And why not? They invented it.

I am not a big fan of ZF transmissions. They are great behind a small gas engine that develops the torque at high RPM'S say for a Fiat or a Alfa Romeo car. But, put them behind a diesel engine engine that develops a lot of torque at low RPM'S as a Cummins and or Caterpillar will do, they fall apart. This is based on experience when ZF transmissions are used behind diesel engines.

Those that are asking for additional gears are you using T/H mode in your trucks when towing and or hauling?

I know my 2008, 6.7L Cummins, with the 68RFE auto, Mega Cab, 4X4, with 3:73 gears and LT285/70R17 (which equates to 33X11.5R17) tires is nearly 13 years old pick-up truck now. But I do not have any trouble maintaining my road speed and fuel economy when towing my Cedar Creek behind my truck at 65MPH and 1650RPM's. I just realize that it is a 13'-6" tall wind brake behind me. I do not care how many gears I have in any transmission this will not improve the fuel mileage when towing a wind brake.

I have tracked my fuel mileage since new and it is hand calculated at every fill-up. When towing my trailer in T/H mode, I can achieve 12 MPG's on level flat interstates roadways, with no headwinds doing 65 MPH, my normal towing speed. With a forty MPH headwind this will drop me to 8.4 MPG's. In the mountains I have maintained 55MPH in 5th gear at 1950 RPM'S on I70 and the fuel mileage was 10.5. When I am not on the interstate roadways but on a two-lane my fuel mileage is closer to 11MPG's.

Maybe for those that want more speeds in a transmission they may need a GAS ENGINE vehicle.
 
Who needs a lot of gears, when you have a lot of torque!

Cummins ISL Spec Engine Data
Compression Ratio 16.6:1
Horsepower 280 - 400 HP
Torque
Range 700 to 1255 ft-lbs

And they stuff that same transmission behind the 6.7...

Plus that Allison will stand the grief for hundreds of thousands of miles even with that ISL set at 350 hp...

My point is that 6 speeds should be plenty...already is for people out making a living with these things...
 
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