I thought about this one the other day. With these 6, 8 and 10 speed automatic transmissions that they're building, do they still have a lockup torque converter in top gear? My Ranger has a 4-speed with a lock-up converter. You can feel it engage once the throttle is let out a bit and you're going over 50-55, you can also see the RPMs drop slightly. My 2017 Mustang has the 6-Speed ZF automatic transmission and I've never felt the similar sensation of a false "7th" gear from a converter lockup, it seems to free-spin like the old 3-speed GM transmission in my Catalina, which has no overdrive or torque converter lockup.
Yes they lock up. In fact because they have so many closely spaced gears, the torque converter is locked up most of the time. That’s probably why you don’t feel the engagement. Because of this, they also run cooler.
That's interesting. They must have really improved that design element to make it practically unnoticeable compared to old 4-speeds.
Maybe it's because you drive Fords. All my GM's had 4-speed autos, and I never really noticed the lockup.
That's possible. But I also had this Ranger's transmission rebuilt and they did a bad job, it clunks when it downshifts into 1st after it's warmed up, most noticeable with very light braking and coasting down through 20 mph. Seems to shift fine otherwise. I mainly notice the lockup because I hear the RPMs drop and the truck accelerates a hair like it changed to another gear.
Lock up torque converters have been around for a long time. The Studebaker Automatic Drive (co-developed with Borg Warner circa 1950) had one as did the Packard Ultramatic (1949). Lock up converters fell out of favor due to cost until the gas shortages of the 1970s and enactment of the CAFE gas mileage standards.
That's what I figured they were implemented as a reaction to and when they were first introduced. I didn't realize they were developed that early. It was a good idea for reducing fuel consumption. I've noticed the truck will drop down around between 300-500 RPM when it engages. I figured with the engines and over a half dozen speeds in modern transmissions, the fuel economy improvement was enough to drop them again.
CAFE regulations have become so ridiculous and onerous that manufacturers today are scrambling for every fractional MPG improvement they can get. That's why we have nonsense like auto stop/start, cylinder deactivation, 10-speed transmissions, CVTs, low-tension piston rings, and alternator cutoff in today's cars, and it's only going to get worse. Those "features" are of no benefit at all to the customer, quite the opposite in fact.
Some of the technology could be good if it worked properly. The problem is the design and development is done too hastily, and the manufacturing is engineering down to price point, rather than a quality level. So the result it unreliable garbage.