Chevy Diesel News & 8-speed Trans. PLUS Ford/Chevy 10 speed Trans.

[Haoleguy]

I'm guessing that auto/truck manufacturers will jump to continuously variable transmissions before we get too crazy with distinct transmission speeds. Fendt's vario CVT seems to be well accepted in the tractor world.

 

[WilliamBos]

I'm guessing that auto/truck manufacturers will jump to continuously variable transmissions before we get too crazy with distinct transmission speeds. Fendt's vario CVT seems to be well accepted in the tractor world.

The Vario set a bench mark that others are still trying to follow. While JD still insists on using three clutch packs in theirs, Vario uses none, and is less failure prone because of it. Also having the CVT fluid separate from the hydraulics is another genius idea.

 

[TheGoose]

+1

Totally agree.

Personally I think some sort of electronically controlled split range rear end would be better than an 8 or 10 speed transmission. For the way that most of these vehicles are utilized, even those that tow a lot, there is a point of diminishing returns with the number of gears in a transmission. The gas and diesel engines in pickups are designed to make power over a very wide range of RPM, whereas in the over the road trucks the diesels are often really suited to only a limited RPM range therefore they need more gears to keep them in the smaller sweet spot. For mileage gains I think you'd be able to realize more benefit and a larger difference in final drive ratio by adding a split range rear end.

 

[WilliamBos]

That would be a disaster. So many seat covers cannot drive a truck with a 2 speed rear axle, putting one in a light duty truck would be a disaster.

 

[TheGoose]

It would need to be "automatic"

 

[mikehaugen]

It would need to be "automatic"

not sure that it would need to be automatic, but probably better if not a constantly shifted gearbox. Say a 5 or 6 speed tranny with a 2 speed rearend with like a 1:1 and a 1.3:1 that you would only switch when pulling a heavy load or in mountains. That would simplify things a little, instead of a complicated auto shifting setup.

 

[Diamondpilot]

I have also said for years there needs to be a computer controlled automatic split rear end.

Chris

 

[CharlieS]

Personally i think they are trying to reinvent the wheel. Years ago heavy trucks had 16 or 20 speed transmissions simply because of the limited rpm range those engines operated effeciently in. Cummins in particular had a 300 rpm range that give maximum torque. With the advent of wider torque curves in those big diesels less gears were necessary resulting in the 13 speed and 10 speed boxes and eventually graduating down to 6 speeds in some cases. SO i see little reason for a 10 speed in a pickup today with the broad torque curves and power band of todays engines compared to 25 or 30 years ago. On the rare occasion closer gears are needed simply go with a 2 speed axle. That can be done even with an automatic transmission. We proved that 30 years ago with a one ton gm and an automatic. The biggest challange was finding a convient location for the splitter button.

 

[RobertN]

I have noticed a number of Cummins 4BT conversions on Youtube. Someone even put one in a '68 or so Camaro. If these guys can do this and have good driveability, then a large 4, or a smaller 6 would work fine in a 1500 series pickup.

Cummins 4bt powered Ford Ranger Part II - YouTube

69 Cummins Camaro 4bt drag - YouTube

Cummins 4bt f150 - YouTube

1994 Chevy Cummins 4bt diesel conversion 4x4 on the move - YouTube

 

[BIG DOOLEY]

What does the 10 speed give you that the 6 and 8 speeds don't (besdies an extra 4 or 2 gears)?

And I mean for everyday, normal driving, not towing something heavy up hills and mountains? My 6 speed already shifts way too much for my liking on flat ground.

It allows the engine RPM's to stay in the peak power/effiency range.

Allowing the engine to run in the best part of the torque curve will get heavy loads moving easier and keep you rolling up hills while still trying to be efficient.
Same applies to everyday driving.