8 Speed Auto for HD trucks

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.

My Ford 6-speed transmission is a huge improvement over previous 4-5 speed, but IMO, an 8-10 speed in a HD model is going to be more complex/problematic, when towing heavy. Just another reason to raise already inflated prices of new trucks.

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

Lessmore wrote:

carringb wrote:
Ford will also be introducing a 10-speed for 2020 model year.

https://www.tfltruck.com/2017/08/2020-ford-super-duty-10speed-automatic-10r140-f250-f350/

Isn't that the 10 speed transmission for rear drive vehicles...that has been co developed by both GM and Ford ? In the past number of years Ford and GM have co developed/designed transmissions, also including front wheel drive transmissions. Good idea.

The 10R80, was the co-development with GM, it has been out for over a year, in the F150, and the new Exp/Nav. I'm not sure if it is in the Mustang yet. The transmission that was mentioned is the new 10R140 (Bigger and beefier).

The announcement that ZF is making a 8, good for 1000 FtLbs, does not stack up very well. The latest Diesels are already at 950 FtLbs, and it will only be a few years until someone crosses the 1K mark.

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.

I like the idea of 10 speeds for a HD gas rig. However I will never purchase any CVT transmission vehicles..... problematic for sure. For some reason Nissan loves using them... in my personal experience it's a no go...

gbopp wrote:
Why can they make multi-speed transmissions but, the CVT doesn't seem to work properly or hold up on heavier duty vehicles :?

a friend of a friend had one in a fiat 500 replacment was 18,000 cdn ,ya my eyes bugged out out . they work by pushing a segmented 'belt' uphill while the pulleys squeeze on it to change the diameter ,work fine in snowmobiles , cars ..........maybe

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!

gbopp wrote:
Why can they make multi-speed transmissions but, the CVT doesn't seem to work properly or hold up on heavier duty vehicles :?

A family member had a CVT transmission in a new Jeep. Problematic transmission. For me if the vehicle has a CVT...it's a deal breaker, after this experience.

carringb wrote:
Ford will also be introducing a 10-speed for 2020 model year.

https://www.tfltruck.com/2017/08/2020-ford-super-duty-10speed-automatic-10r140-f250-f350/

Isn't that the 10 speed transmission for rear drive vehicles...that has been co developed by both GM and Ford ? In the past number of years Ford and GM have co developed/designed transmissions, also including front wheel drive transmissions. Good idea.

That's exactly what I was hoping for when we buy in 2020!
I have the ZF in my Challenger and it is a great trans.

Why can they make multi-speed transmissions but, the CVT doesn't seem to work properly or hold up on heavier duty vehicles :?