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Discussion Starter · #1 ·
I've said before that if they can build one to live behind the Hellcat and Demon they can build an 8 speed that will hold up to HD truck use-at least behind a Hemi but I think behind a Cummins too.


Well, it looks like ZF is getting ready to release their "Powerline" (aka 8AP) transmissions, loosely based on the 8HPs that many of us have. This article says they are for class 5-8 trucks, however they've already put one in a Ram 3500 and ostensibly tested it.




https://www.trucks.com/2018/06/20/zf-8-speed-transmission-commercial-trucks/
 

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IB4 shift knob criticism.
 

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Can someone explain how this is a good feature for trucks that re expected to tow/haul heavy loads?

Fuel-saving techniques designed for commercial vehicles include a “sailing” feature, which automatically places the transmission into neutral during a steep downgrade.
I mean I can see it being useful for slight downhill situations to allow the pull of gravity cancel out with wind resistance and driveline+tire friction, but steep downgrades?
 

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Discussion Starter · #6 ·
Can someone explain how this is a good feature for trucks that re expected to tow/haul heavy loads?



I mean I can see it being useful for slight downhill situations to allow the pull of gravity cancel out with wind resistance and driveline+tire friction, but steep downgrades?

I wonder if they are trying to describe something like DFSO where the TC locks and the momentum of the vehicle runs the engine while fuel is shut off. Our trucks do that
 

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I wonder if they are trying to describe something like DFSO where the TC locks and the momentum of the vehicle runs the engine while fuel is shut off. Our trucks do that
But in that situation in current production vehicles, the transmission is still in a forward gear, right?
 

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Discussion Starter · #8 ·
But in that situation in current production vehicles, the transmission is still in a forward gear, right?

Correct; IDK a whole lot about the site that wrote the article so I suspect that if it is a IDFSO like system they just may not be as knowledgeable as they think they are.


Or maybe that's what it is and there is some sort of pump in the new transmissions that is driven off either the output or input shaft
 

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If you take it literally, it says, it puts the transmission in Neutral, something NOBODY EVER SHOULD DO IN STEEP DOWNHILL CONDITIONS!
I do not believe, that's really the case and the author might misunderstood the feature.
Our trucks actually switch into lower gear and hold it, when you go downhill and step on the brakes short. This is more like it.
I do believe that there is a sail feature at very slight slopes, where the vehicle can maintain it's speed without needing engine support.
 

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I agree, the "sailing" "feature" sounds like a terrible idea on a commercial vehicle or HD truck. With that said, the HD Ram's desperately need a new transmission for the gassers and this can't come soon enough.
 

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Discussion Starter · #11 ·
, the Ram's desperately need a new transmission for the HDgassers and this can't come soon enough.
FIFY

I honestly don't see why they don't already make the ASC69RC an option on the 2500 and 3500 with the Hemi, its geared better than the 66RFE and its available on the chassis cab 6.4s. I don't think the bellhousing is different on the 5.7 and 6.4; AFAIK the Hemis all use the LA smallblock bellhousing pattern just without the top bolt.

How much more bulletproof can a transmission get than one with a capacity twice as great as the maximum output of the engine its hooked to?
 

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FIFY

I honestly don't see why they don't already make the ASC69RC an option on the 2500 and 3500 with the Hemi, its geared better than the 66RFE and its available on the chassis cab 6.4s. I don't think the bellhousing is different on the 5.7 and 6.4; AFAIK the Hemis all use the LA smallblock bellhousing pattern just without the top bolt.

How much more bulletproof can a transmission get than one with a capacity twice as great as the maximum output of the engine its hooked to?
Thanks, I fixed my typo.
Perhaps the pesky reverse gear :) The gasser can't handle a 3.54/1 reverse gear that the Aisin has, the RFE has a 4.44/1. I still think a ZF would be a great transmission that will allow the 6.4 to perform as it should without a huge gear gap.
 
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