Why You Shouldn’t Feel Bad About Getting An Automatic Toyota Supra

The addition of a manual gearbox to the Toyota GR Supra has been widely celebrated by enthusiasts, but the automatic is still the better choice for many. While discounting any manual gearbox option might get me banished from certain auto enthusiast circles, I believe the ZF 8HP automatic can go toe-to-toe with the manual gearbox that’s available in the Supra and even outperform it on track. Don’t let the appeal of a clutch blind you to what’s turned out to be one of the best gearboxes available for a modern sports car.

An automatic was the only available gearbox on the debut of the fifth generation Toyota GR Supra to the dismay of many enthusiasts as Parker wrote recently, but the ZF 8HP 8-speed is built for maximum efficiency with just five shift elements.

These shift elements are combined with three multi-disk clutches and two brakes that result in a lightweight package that shifts quickly. That configuration allows the 8HP to only open two shift elements per gear and can result in shifts that are as fast as 200 milliseconds depending on the configuration. This type of shift speed puts it in line with the 6-speed automated sequential that Lexus put into the LFA supercar.

(Full Disclosure: Toyota loaned me a 2023 GR Supra for a week with a full tank of gasoline.) 

What Makes The ZF 8HP So Good?

The ZF 8HP became an enthusiast gearbox almost by accident. Its primary design goal was to be as efficient as possible in order to improve fuel economy. But here’s the great thing about an efficient mechanical design: it doesn’t discriminate based on use case, which is how we ended up with a gearbox that offers excellent shift behavior as a side effect of fuel economy goals.

The basic idea of the design with minimal shift elements being opened for each gear change is to reduce the number of parts that are moving in order to prevent losses and increase efficiency to meet fuel economy targets. This behavior is know as a clutch-to-clutch shift as it only requires one shift element to be released and one to be engaged in order to shift to the neighboring gear.

One of the things that always confounded me was why the ZF 8-speed was so much better than the ZF 9-speed, and the answer partly lies in how they are packaged. Since the 8-speed is most typically used in rear-wheel-drive applications and set up in a longitudinal configuration, the case can be longer and have space to arrange various components. In comparison, the 9-speed is set up for transverse application in front-wheel-drive based cars so gear sets have to be nested and dog clutches have to be employed in order to maximize space inside of the case, which can impact shift behavior.

On the other hand, with plenty of space in the case, the 8HP skips the dog clutches for conventional ones and is able to employ just five shift elements which are split between three clutches and two brakes. The brakes lock the rotating shaft to the ground while the clutches are used to couple the rotating shaft to each other. The internal arrangement of the 8HP is so efficient that ZF was able to fit components for an 8-speed in the same size case that they used for their 6HP 6-speed and even reduce the weight of the whole assembly compared to that 6HP. Not only does the 8HP only have the five shift elements seen above, it further maximizes that efficiency by only needing to use three of those five elements in any given gear.

 

Torque converter is probably the dirtiest phrase that you can say to a car enthusiast but the unit that’s coupled to the ZF 8HP is designed in a similarly efficient manner as the gearbox. The torque converter for the ZF 8HP makes use of a twin-torsional damper which is a device that helps to reduce vibrations. At first glance, this doesn’t seem like a benefit for enthusiasts, but that damping allows for the gearbox to be able to select gears earlier, helping that shift speed without sacrificing low-speed performance. That damper works in conjunction with multiple clutches that are customized to the application of the gearbox to provide earlier gear selection without unwanted vibrations.

Toyota Takes The ZF 8HP Racing

 

The technical details only tell part of the story and the biggest proof of the effectiveness of that eight-speed automatic may come in the fact that Toyota chose to use it in its GR Supra GT4 race car with some select modifications. The first thing that they did is to convert it into a seven-speed by removing the overdrive gear, which is primarily designed for highway cruising and not necessary on a race track.

In addition to that, the computer running the gearbox gets some motorsport-specific programming to account for things like a pull-and-hold downshift function. Minus some small tweaks, the gearbox itself stays mostly the same internally. This is a huge endorsement of that automatic unit as many other variants of GT4 cars will often go for purpose-built sequential gearboxes.

In addition to the Supra, racing versions of the 8HP have appeared in cars such as the BMW M235i Racing and the BMW M4 GT4. Much like the Supra they get customized programming and supporting modifications such as a racing differential but internally they are mostly the same as their road-going counterparts.

All of this mainly applies to a very specific group of track enthusiasts looking to maximize performance, as slotting an H-pattern manual into gear is very satisfying and can often be the sole reason that some people choose a specific vehicle. The paddles in the automatic Supra provide almost the same level of fun while also offering a highly efficient shifting experience so giving the automatic gearbox a try might offer a surprise for many enthusiasts.

Driving Impressions And The Fun Factor

Rowing your own gears can be fun, but the average manual shift takes more than twice as long as what the ZF 8HP is able to accomplish on its own and isn’t as efficient for those looking to maximize their performance on track. The shift time really comes into play when you want to skip gears, which can come often on track when approaching corners. The 8HP is designed so efficiently that it can use those two shifting elements to not only do a single gear change but in certain cases can drop multiple gears quickly going from as high as eighth down to second incredibly quickly when necessary.

While the paddles may get close to the level of fun of the H-pattern manual that is available I do have to concede that the manual is still the best option for those who aren’t looking for ultimate speed on track and just want something fun for their commute or back roads because Toyota did such a great job with the shifter and the clutch. Just like the automatic option, the manual gearbox is also manufactured by ZF and comes from their S6-53 series. This gearbox is also employed in variety of BMW products but also makes an appearance in the Alfa Romeo Giulia Quadrifoglio and diesel Jaguars in Europe.

The specific version of the S6-53 used in the Supra is the GS6L50TZ model which is loosely based on the GS6L40LZ found in the BMW Z4, but it’s easy to see that Toyota spent time customizing it for the application because it has better shifter and clutch feel than any modern BMW manual that I’ve experienced. Toyota refers to the GS6L50TZ as the L-500 in their service documentation. Shifter movement feels incredibly crisp and the gate spacing is laid out in a very straightforward way while the knob feels satisfying to hold making it hard to find much to complain about when it comes to the shifter.

The clutch pedal does have some of the slightly rubbery feel that is often present in manual BMWs, but it seems less pronounced in the Supra while clutch pedal travel is pretty similar. The pedal box area in the Supra is spacious and since that firewall was originally designed with the clutch pedal mount in mind, everything is laid out in a planned way which is easily compatible with my size thirteen sneakers. The brake pedal is placed close enough to the accelerator for heel-toe action and if you don’t want to be fully involved, the iMT rev-matching functionality will help you along.

My main gripe with the clutch pedal comes from the fact that it occasionally seems to have delays returning after a quick shift and it feels like the return of the clutch pedal isn’t as linear as when it is pressed as it seems to slowly come back up and then slap the bottom of my foot when it gets close to the top of its range. This is probably the biggest area that stood out for me as a detriment when it comes to comparing upshifts between the manual and the automatic.

There’s Nothing Tragic About Getting The Automatic

We often criticize paddle shifters in automatic cars for their delay, but in the case of the Supra it often shifts faster in those lower gears than the manual due to some of the delays with that clutch system, which is why the automatic is the better option for track duty. That clutch delay is not always prominent and appears to be a feature of a component called a Clutch Delay Valve (CDV) that is intended as a buffer on clutch action in order to reduce shock on the drivetrain and improve durability. Searching some enthusiasts groups shows that the CDV can be removed, but I can’t say what the long-term effects of removing such a part would be as automotive manufacturers don’t typically add parts don’t typically add parts unless there is good reason for it.

BMW and Toyota obviously didn’t believe that the S6-53 manual gearbox could be modified to be their best option for racing duty as they both run modified variants of the ZF 8HP automatic in their race cars. I agree with their decision when it comes to competitive driving on track as the 8HP appears to be a better fit on track even though the manual gearbox is more fun in a variety of other situations when it comes to street driving.

But this isn’t one of those cases where you should feel bad about buying the automatic or assume it’ll be the slower option. This is an extremely well-designed gearbox that offers a lot of benefits for track driving and is, in my opinion, often more fun to drive fast.