- Author: Mike Souza
- Subject matter: 10R80/10L90
- Issue: Comparing versions
Triple center clutch assembly key to unit’s compact size
Approximately 10 years after Ford and General Motors joined together to develop a six-speed front-wheel-drive transmission, they have done it again, developing a 10-speed rear-wheel-drive transmission (Figure 1). The GM version designated the 10L90 was first introduced in the late 2016 Ultra Performance Chevrolet Camaro ZL1, while Ford’s version the 10R80 was first introduced in the 2017 F-150 Raptor powered by the new 2nd generation 3.5L Ecoboost V6 with a 450-ft. lb. increase in torque. GM offers this new 10 speed in the Camaro, Corvette, Seirra and Silverado, just to name a few models for 2018. The GM 10L60 will go behind the 2.0L and 3.6L 4-cylinder engines. The 10R80 will be powered by the 3.0L V6 whereas the 10L90 will be mated to the 4.2L V8 engine. This new 10 speed is offered in the 2018 Ford F-150 Supercrew as well as the Ford Ranger. The 2.3L 4-cylinder engine will be equipped with the 10R60 while the 2.7L, 3.0L, 3.5L V6 and 5.0L V8 will be equipped with the 10R80. Ford has already registered patents for an 11-speed transmission. This will be Ford’s first transmission built without the use of any cast iron components.
Engineering has minimized spin loss, using ultra-low viscosity fluid with a variable-displacement-vane type pump (figures 2 & 3). An internal bypass system reduces parasitic energy drain and speeds warmup after a cold start. GM developed a dedicated oil cooler system for the Camaro models, while Ford focused on towing capability with an electric pump linked to the engine to allow stop-start operation. The torque converter (260mm) is 1 kg lighter than the converter on Ford’s previous eight-speed rear-wheel-drive transmission. The pre-programmed lockup slip percentage dampens out low-speed torque fluctuations and permits the engine to run at lower rpm levels. Lock-up is active in first gear. This is especially useful with the three over-driven ratios that are set high enough to keep the engine cruising rpm lower. The torque converter is also a new unique design. The converter clutch has been move to the front of the converter instead on the back cover. It is no longer flat; it’s now curved to the contour of the impeller. This will make it quite interesting for the converter rebuilder to not only bond the clutch material to the turbine, but also machine the clutch-apply surface area of the impeller (Figure 4).
Triple center clutch assembly
The triple center clutch assembly (location shown in Figure 6 cutaway view) is the key to the compact size of the transmission, with four planetary gear sets and six clutch assemblies, four rotating and two braking. There are four clutch components applied and only two released during each gear change for less drag and maximum efficiency. This allows for most of clutch-to-clutch shifts to perform quicker, except for a rare third-to-first downshift using freewheeling and a strategy referred to as passive clutch engagement. First gear to sixth are under-driven, seventh gear is a 1:1 ratio and eighth to tenth gear are over-driven. Both companies use a smart shift control system to utilize the span of ratios quickly and intelligently. The Ford F-150 real-time-adaptive-shift-scheduling algorithms monitor over a dozen powertrain and driver control signals to perform the correct gear at the right time in both normal and sport mode. A stacked numerical (1 through 10) readout in the gauge cluster identifies the currently selected gear ratio in real time (Figure 5). During four-wheel drive off-road use, the engine start-stop is disabled. Chevrolet uses a control system to make very rapid shifts in sport mode. GM claims the new Camaro HydraMatic upshifts faster than the Porsche dual clutch PDK known as the sportiest DCT on the market. Chevrolet claims the 1-2 shift is 36%, the 2-3 and 3-4 shift being 27% and 26% faster than the Porsche PDK (clutch ID & apply chart shown in Figure 6).
There are eight to nine solenoids located on the valve body (model dependent, with stop/start feature). Six normally low linear solenoids (shift), one normally low variable force solenoid (TCC) and one normally high variable force solenoid (line). There are three shift pressure solenoids “on” and three “off” in park/neutral, four “on” and two “off” in reverse and during each forward gear shift change. One “on/off” solenoid if equipped with stop/start feature (solenoid ID & apply chart shown in Figure 7). Failsafe gear command can be from 2nd gear and reverse to 8th gear and reverse depending upon which electrical solenoid or hydraulic code set in the external transmission control module (TCM). There are also several failsafe command mode strategies dependent upon the code type category.
Example: Type A DTC
- Autostart/autostop = disabled (if equipped)
- Grade braking = disabled
- Manual shift control = disabled
- Neutral idle mode = disabled
- Powertrain (downshift) braking = disabled
- Tap up & tap down = disabled
- TCC control = disabled
- Transmission adaptive pressure control = freeze current adapt values
- (P2736, P2739) transmission gear allowed = reverse or gear 3
- (P2738) transmission gear allowed = Reverse or Gear 5
Driving the Ford version
While in Ohio on business for Seal Aftermarket Products, I rented a 2018 Ford F-150 with this transmission, and of course that meant I had to do my usual car rental research (drive it like I stole it). The start/stop mode was a little annoying but that feature can be disabled with a press of a button on the dash. I must admit, I’m not a huge fan of Fords, but with this transmission I would be tempted to buy one. Of course, I would have to wear a Nixon mask so my friends don’t see me driving it.
Now that wasn’t nearly as complicated as the Mercedes units covered in the last two articles was it. More in-depth information about this new 10 speed will be covered in future articles and seminars. Thanks for reading this article see you soon!