8 Speed Auto for HD trucks

ScottG wrote:
I think the advantage here will be because of the deep first gear of the ZF's and the 3.42 gearing your stuck with in the RAM. Hopefully that low gear will improve the SRW 3500 off-the-line performance and bring it up to that of the current trans with 4.10's.

The Aisin option already does that, just fine!

Off the line performance will always be controlled by torque management to protect the drive train. That will not change with more gears. Flop the pedal to the floor with a new RAM and nothing much happens, however roll into the throttle and they respond quite well.

A jacket rabbit they are not. Once one learns that and how to drive it, most are very happy with their RAMs.

I don't think that transmission is going to be an option with the Cummins. I'll bet it's gas engine only. I surely love it in my 1500. It will be a great option in the HDs. Much better gear selection than the current Ram 6 speed.

I think the advantage here will be because of the deep first gear of the ZF's and the 3.42 gearing your stuck with in the RAM. Hopefully that low gear will improve the SRW 3500 off-the-line performance and bring it up to that of the current trans with 4.10's.

wnjj wrote:

monkey44 wrote:
HAHAHA == pretty soon we'll be spending all our time in the shifting mode, and no time in the driving mode. Can't wait for the announcement:

Ladies and Gentlemen, start your engines - we now have a twenty-speed Allison for your shifting pleasure.

With computer controls and plenty of gears, there’s no reason to shift more often. The system just has a lot more gears to pick from depending upon loading and can skip to whichever gear matches the demand.

Our Yukon 6 speed would probably act much like an old 3 speed at towing since the first 2-3 gears get you to highway speeds when turning high RPM. The upper 3 just keep dropping the RPM down. I find “holes” in the gear spacing just driving it empty. It really needs a 1.5 and 2.5 gear or maybe more.

Bring on the 8-10 speeds!

Will towing get easier

mowermech wrote:
OOOH, WOW! an 8 speed automatic!

Oh, wait, didn't GM make an 8 speed automatic sometime in the 1950s, by putting a dual range in the old 4 speed Hydramatic and "beefing it up"? Didn't they intend on putting it in heavy duty trucks? And, wasn't it a failure because very few drivers wanted it?
Maybe now the heavy duty truck drivers are ready for a full-on automatic.
Of course, it could very well be that my memory is faulty. That happens a lot now that I am over 75!

To be fair, the transmissions being discussed are for light and medium duty trucks (2500 though 5500). Automatics have been standard across most of those two markets for over a decade. Its to a point that finding a 'manual' transmission requires a special order.

Me Again wrote:
With diesel engines wide flat torque curves, I just do not understand the need for more than 6 gears. Except for maybe RAM 68RFE that has tall 1st and 2 gears. Might be easier to just fix the ratios of the existing box than add more gears.

But how about two reverse gears, with a granny gears for the second one. Would be great for spotting trailers etc.

It's less about power more about efficiency. The engine may be able to compensate for the wrong gear ratio but you will lose MPG doing it.

Keep in mind companies buying fleets of trucks care less about bragging rights and more about fuel costs.

Eventually, I expect they will move to a CVT but the Big3 aren't going to risk the reputation of their massively profitable pickups until they are comfortable that it will work and be reliable.

MFL wrote:

As mentioned, a second granny reverse gear would be a nice addition to a HD truck. If only one reverse gear, it should be a granny. Really no reason to back a HD truck at higher speed. Years ago, I had a truck with 5-speed standard, that had granny 1st/reverse. It worked great for backing RV, and also at the boat ramp.

Jerry

I never got that on just about any vehicle (not just HD trucks). It's rare to have to back up more than 100yds and never above 15-20mph. The vast majority of time, it's less than 50' and below 5mph.

Me Again wrote:

But how about two reverse gears, with a granny gears for the second one. Would be great for spotting trailers etc.

That is the one consideration for getting 4x4 that I consider valid (though not overwhelming) when looking at tow vehicles. With low range, you effectively have granny gears.

That said, just bought a 4x2 since we had the last truck for 5 yrs and other than to verify the 4x4 worked every few months, only used it once and that was only because we had 4x4 and I never would have done the stupid thing if I didn't have 4x4 (tried to drive over 6' wide muddy area between two paved lots rather than driving around and the rear tires sunk in).

OOOH, WOW! an 8 speed automatic!

Oh, wait, didn't GM make an 8 speed automatic sometime in the 1950s, by putting a dual range in the old 4 speed Hydramatic and "beefing it up"? Didn't they intend on putting it in heavy duty trucks? And, wasn't it a failure because very few drivers wanted it?
Maybe now the heavy duty truck drivers are ready for a full-on automatic.
Of course, it could very well be that my memory is faulty. That happens a lot now that I am over 75!

i'd take a 10 speed with my powerstroke - additional gears with tighter spacing will ensure you always have a proper gear.