28 Thoughts On Modern Domestic 6 Speed Automatics

Alternative Auto Performance has been working with the modern 6-speed automatic’s that come in several models from Ford and GM for some time now. We started to develop and are offering tunes that will greatly improve over all performance in many of these new vehicles that are equipped with these 6-speed automatics.

Ford is using the new 6-speed auto’s in many of its mid to full size models. Most notably the current F-150’s, and non diesel gas burning Super duty’s, 5.0L Mustang, Taurus and many more.

These modern 6-speed auto’s are touted as contributing to improving fuel economy along with improvements in other performance areas of these new vehicles.

From a performance stand point, these 6-speeds auto’s can make a big difference under most driving conditions. They have more non overdrive forward gears (1st through 4th) that can greatly increase acceleration and response. They have very steep 1st gear ratios, and reasonably closely matched gears to follow. 5th and 6th gears are overdrive gears.

And one very cool feature is 4th gear is not a 1 to 1 ratio as people would assume like in most other 4-speed and 5-speed automatics where 3rd or 4th are considered high gear and were generally a 1 to 1 ratio. On these modern 6-speed auto’s from both Ford and GM – 4th is around a 1.15 ratio. Which places its ratio close to 3rd gear, which places its ratio close to 2nd gear, and 2nd is close to 1st ratio.

What this does is not cause a very large RPM drop when going through all the gears. Keeping the engine very happy, and in an operating range that feels good under almost any driving and load conditions.

It’s to bad that these modern 6-speeds didn’t exist just a couple of decades ago. Many other/older engines that made substantially less power and TQ could have performed and towed much better had they simply had a 6-speed automatic trans of this nature to make better use of their operating range and RPM’s.

The number one complaint we’re seeing these days with most automatic transmission programming from the factory is still some poor performance around town,  when towing, and also and more commonly  what I’ve labeled in the past as “intermediate” speeds; where you’re not really just cruising at 65mph or 70mph, etc. It’s where you’re constantly increasing and decreasing your speed. And just plain old city type driving.

I get lots of complaints that these transmissions don’t know what gear to be in. Hunting some times, not down shifting quick enough and etc. What is really going on is quite simple, and I’ve stated this before…. It’s a proving thing in the car industry that for optimal fuel economy that you want to keep you RPM as low as possible when driving around. Even though the engine may be lugging and bogging so to speak – it will consume the least amount of fuel this way. This is why these very current and new 6-speed automatic equipped vehicles under light loads will end up in the highest gears like 6th or more, as early as 35mph with the TQ convertor locked as well. This will on some vehicles make them cruise at RPMs as low as 1100 to 1400rpm!!! Then as you tip into it, they continue to lug a bit, and then eventually maybe down shift one or two gears to meet the driver’s acceleration requirements under the conditions. The problem is this super low RPMs and early shifts just doesn’t feel good, and lacks responsiveness.

We correct most if not all of this with our in house custom tunes for these new/modern automatic vehicles. Above all things, we let the Torque convertor do what it was meant to do… Multiply TQ!! With our custom tunes we do not even let the TQ convertor lock at all until the highest overdrive gear is engaged and cruise speeds of a minimum of 60 to 65mph have been reached. This tuning feature alone that we do with the TQ convertor makes the most substantial and proven gain in “seat-of-the-pants” performance with our stuff. And can also contribute to decent gains at WOT in the ¼ mile in many applications.

Don’t be fooled into thinking that a locked convertor is the way to go all the time. This is a belief that is derived from people who are used to big and instant TQ from very large and powerful applications like big cubic inch motors and high TQ producing Turbo diesels. This does not apply with smaller higher revving gas motors. Even the larger stuff like the 6.2L gas engines, and larger feel significantly better under most driving conditions while accelerating when the convertor is unlocked. But gas mileage can suffer depending on overall driving style.

Aside from the TQ convertor lock-up schedule, we very extensively revise the shift schedule too. We very greatly enhance the Day to Day around town feel with making them downshift quicker, and move around and delay the upshift a bit as well.

I’ve stated this before that most of the gains and enhancements with our in house tunes (especially automatic cars & trucks) with everyday in town driving tend to feel much better more from what we do with the trans and TQ convertor schedule re-tuning, than actually adding some power to the engine. Although our tunes do add throttle response and TQ across the operating range, especially with our 93 octane tunes.