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I found a link on the Fiat website to the Comfort-Matic automated manual transmission that will be in the PM diesel when it arrives. Ram is calling it the M40. The pdf files are a bit too big to upload here (although only ~250kb each). PM me your email and I can send them, or if anyone has a way of hosting them for d/l let me know and I'll send them along. Or you can register at Fiatcamper.com and download them.

The transmission looks like it might be a bit unusual for most drivers who are used to an automatic and/or have never driven a manual transmission, particularly when parking on an incline - don't leave it in neutral, and always use the parking brake.
 

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It is mechanically a manual transmission, except it's (mostly) not subject to operator ineptitude. I would expect the mechanicals of the transmission to be near indestructible. It will likely need a new clutch friction disk at some point - just like a manual transmission would - mine have gone 400,000+ km in other cars. Most conventional automatics don't last that long.

The question mark is the controls, sensors, and actuators. The transmission in the North American market that is the most similar in concept to the Fiat M40 AMT is the (much-reviled) transmission in the little smart fortwo. The transmissions themselves in those cars never break, but the actuators go wonky - and people love to hate the way they drive, partly because of the interruptions in power during shifting, partly from a tendency to often pick the wrong gear to be in (fixable by using manual mode). I suspect that the Fiat AMT will be more of the same, but hopefully with better shifting and without the smart's tendency to lose its mind once in a while ...
 

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It is mechanically a manual transmission, except it's (mostly) not subject to operator ineptitude. I would expect the mechanicals of the transmission to be near indestructible. It will likely need a new clutch friction disk at some point - just like a manual transmission would - mine have gone 400,000+ km in other cars. Most conventional automatics don't last that long.

The question mark is the controls, sensors, and actuators. The transmission in the North American market that is the most similar in concept to the Fiat M40 AMT is the (much-reviled) transmission in the little smart fortwo. The transmissions themselves in those cars never break, but the actuators go wonky - and people love to hate the way they drive, partly because of the interruptions in power during shifting, partly from a tendency to often pick the wrong gear to be in (fixable by using manual mode). I suspect that the Fiat AMT will be more of the same, but hopefully with better shifting and without the smart's tendency to lose its mind once in a while ...
Nice summation which I happen to agree with. I wouldn't worry about the mechanical function but would never order one of these transmissions without first seeing years of positive data. Too many risks in my opinion compared to either an automatic or true stick. This middle ground of a design solves nothing for me, except maybe when my wife drove the van. She's not crazy about driving a stick shift although she's good at it. I'd consider the diesel with a stick but the automated transmission is a deal breaker until proven in US. And just because it may work in Europe doesn't mean it will succeed here in my opinion.
 

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Here's a pretty fair review of the Ducato with the diesel and the M40 transmission:
Do you find the review positive as it refers to transmission's operation?

I like some aspects, like improved fuel economy, but I'm not sure I'd want a transmission that "may" initiate a slow shift while turning left across heavy traffic, or trying to shift 1st to 2nd on a hill that it can't hold 2nd on, so it shifts back to 1st just to repeat the process. It's hard to tell from video's sound but the 1st to 2nd shift does sound very slow.

I'm also a little concerned how this automated system would allow me to park the van within inches of a wall or other obstacle. A simple test drive may prove it's a non-issue, but I have concerns about being able to control minor movements accurately. These may be non issues but I'd want to test for myself.
 

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Discussion Starter #12
Do you find the review positive as it refers to transmission's operation?
............
I'm also a little concerned how this automated system would allow me to park the van within inches of a wall or other obstacle. A simple test drive may prove it's a non-issue, but I have concerns about being able to control minor movements accurately. These may be non issues but I'd want to test for myself.
I haven't driven one, so hard to say whether it is positive or not. It does point out the way that it operates, with a pause between gears, and I think he covers this in a fair manner. The pause between gears is the "robotic" operation of the clutch, so imagine driving a manual transmission and making gear shifts slowly while you have the clutch pedal fully depressed. This is much easier on the clutch, and should prolong the life of the clutch disc as it will minimize slippage.

On your question about parking, I don't think this will be an issue. Once the transmission is in gear, and particularly if moving slowly, it shouldn't change gears. And you can always override the automatic operation and select gears manually.

I, too, would like to drive one before making a purchase decision.
 

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.....cut.......

On your question about parking, I don't think this will be an issue. Once the transmission is in gear, and particularly if moving slowly, it shouldn't change gears. And you can always override the automatic operation and select gears manually.

......cut.......
Changing gears is not what I meant at all. I know that won't happen.

For example, I'm concerned that if parking inside a small garage, and you need to move the van forward another 3 inches or so, how does the "robotic" clutch actuator handle the clutch so you don't end up accidentally driving through the back wall of the garage?

With an auto the torque converter tries to move the car forward, so the driver can ease up on brake to inch forward. And with manual a driver can feather clutch as needed to also inch forward. But with an automated manual, what happens if you have to step on gas for computer to think you want to move forward? And how will it know you only want to move a couple of inches?

Until I drive one I'm not convinced this operation can be smooth and or controlled enough for my taste, although I hope I'm wrong.
 

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Going for it

Hi, I went to test drive a 2500, 159WB twice past week. I don't think there is any issue moving the vehicle a few inches back or forth. As soon as you let your foot off from the brake the vehicle starts moving very slowly forward, or if it doesn't you'd press the accelerator a tiny bit it and it will move the same as an automatic transmission does, no concerns about that. The same for reverse.

Yes, first to second gear shift is a bit slow, but I drove stick-shift transmissions for many years before and it's okay. I must say that it's almost unnoticeable from third to sixth gear. and once you are at 50+ mph, it feels like an automatic transmission with plenty of torque.

I was very surprised to find plenty of data and documentation online as a "Fiat Ducato 160 Multijet" how it is known in Europe. Fiat claims to have sold only 4.6 million units around the world.

Diesel engine has 5 year/100k miles warranty on powertrain that neither GM nor Ford offer. I own chevy and ford work vans, but the ride comfort of the Promaster was far superior of any of my 9-12 miles gas guzzlers, with superior towing and payload capacity, not to mention the braking power in this thing is awesome, shouldn't have any mayor problem stopping this van fully loaded. I think I'll go for it, I'll be happy with 24mpg, but hope for 27-30.


Ray


Changing gears is not what I meant at all. I know that won't happen.

For example, I'm concerned that if parking inside a small garage, and you need to move the van forward another 3 inches or so, how does the "robotic" clutch actuator handle the clutch so you don't end up accidentally driving through the back wall of the garage?

With an auto the torque converter tries to move the car forward, so the driver can ease up on brake to inch forward. And with manual a driver can feather clutch as needed to also inch forward. But with an automated manual, what happens if you have to step on gas for computer to think you want to move forward? And how will it know you only want to move a couple of inches?

Until I drive one I'm not convinced this operation can be smooth and or controlled enough for my taste, although I hope I'm wrong.
 

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I have driven my diesel/M40 for a bit less than 9,000 miles now. The 1st to second is slow and if you anticipate and let up on the throttle it is even slower. The secret is to keep the pedal down and wait for it. I was caught once or twice thinking I was not going to get through the intersection as fast as I would normally in an automatic. Happens in a shifter with clutch too. You learn to anticipate the lag and use a bit of caution. I'm adapted now and am happy with it. The inching forward is no problem. Climbing into my driveway does require me to touch the brakes to stop the van as it tends to pull in 1st if on an incline even with no throttle.
In exchange for these quirks I get 26+ mpg all the time, smooth shifts above 2nd, a van that hauls up all the interstate hills in high. My former automatics all hunted for the right gear on the slightest hills, in headwinds, and even when meeting trucks. I really did not like that. This is a much better combination. BTW you will not get 30. 26-27 yes easily.
 

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I run 50-60mph on secondary roads and I get 27+ if it is not steep, no cruise control. On interstate I get 26 at 63-65 where I run most of the time on cruise. I do a bit better running the accelerator pedal than using cruise control, usually 1 mpg better. The computer is consistently .5+ below my refill MPG so I report the refill mpg. My long time "B" mpg is reporting 25.4 right now so I would add .5+ and call it 26 for the past 7,000 miles or so. Mountain passes and headwinds lower it to 24+ but I have never run a whole tank there. I estimate my conversion weighs 600-700 lbs, two in the seats. Hope this helps.
 

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RD that milage you are posting is awesome! My 118" diesel only averages 23.5. Not complaining. I do believe that all the stuff I have on the roof, sports case, platform for solar and racks does effect mpg! Cheers
 

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For everyone considering a Diesel Promaster, the above mpg is very accurate. This van is super fuel efficient. Remember any vehicle, when speeds increase mpg' drop. Running 75mph without a trailer I've experienced 22mpg. When I first purchased my diesel van after trading my gas Promaster for it I drove slower on a couple trips without a trailer and duplicated 27-29mpg. The van also sips diesel at idle, approx 1/4 gallon per hour of idle time. I often idle van, 4-8 hours at a time when stopping to sleep on the road for heat when cold outside.
 
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