Zf 8 Speed Vs. Aisin 8 Speed Transmissions: How Do They Compare?

For a agelong time, astir automatic transmissions were written disconnected by enthusiasts acknowledgment to their sluggish, slow shifts. There's a reason why they're commonly referred to arsenic "slushboxes". But since nan mid-to-late 2000s, automatic transmission capacity has — thankfully — improved greatly, to nan constituent wherever manuals are getting difficult to find. According to nan 2024 EPA Automotive Trends Report, manuals now relationship for little than 1 successful each 100 caller car income successful nan U.S..

That's mostly acknowledgment to 2 peculiar 'boxes that person moved nan dial and turned autos from pariahs to afloat accepted parts of nan automotive landscape. Perhaps surprisingly, we're not talking astir fancy, quick-shifting, dual-clutch units, for illustration those prominently recovered successful Volkswagens, Porsches, immoderate BMW M cars, and more. Nope, we're talking nan conventional, torque converter-equipped ZF and Aisin eight-speed transmissions. But really do these 2 comparison against each other?

Both are proven eight-cog systems that person a agelong and illustrious work record. But let's excavation into what makes each of these transmissions great, wherever their shortcomings lie, and really they disagree mechanically.

Turn nan timepiece backmost to nan 2008 exemplary year. "Low" by Flo Rida (featuring T-Pain) was clogging up nan airwaves, and the venerable Lexus ISF arrived connected nan U.S. marketplace — nan brand's first V8-powered sports sedan built to return connected nan BMW M3 and Mercedes-Benz AMG C63.

The F's high-card was its 416 people aspirated horsepower, but what made its manus truthful difficult to hit was nan eight-speed Aisin AA80E automatic transmission, nan first of its kind. Finally, a accepted car that overcame nan slushbox trope, yet provided much than 1 overdrive cogwheel to amended wide substance efficiency. Just ideate what that 18 mpg mixed system would've been without truthful galore ratios successful there?

What besides makes this 'box awesome is that shifts return arsenic small arsenic 100 milliseconds – a lucifer for nan Ferrari F430 erstwhile it debuted. Then, nan torque converter is locked betwixt gears 2 done eight, which intends nan car feels much a manual transmission erstwhile you rotation disconnected nan throttle: You consciousness nan compression. It besides could withstand a respectable magnitude of torque for its day: 406 pound-feet.

That being said, nan Aisin has immoderate drawbacks. Thanks to its mechanical makeup, location are really 2 shifts happening erstwhile nan driver feels conscionable one. This is because, as Motor Frontier explains, location is simply a awesome load transportation betwixt 2 soul clutches, and nan shifting involves 2 elements to disengage and 2 elements to prosecute simultaneously shifting betwixt 3rd and eighth gear. The complexity impedes smoothness. And while the 406 pound-feet torque limit isn't bad for banal power, expanding output via aftermarket tuning tin get adjacent aliases moreover transcend that fig rather easily.

Peter Nelson

In a sense, nan Aisin transmission walked truthful ZF's 8HP could run. It's successful work successful nan existent G8X-generation BMW M3 and M4, and galore different past and existent Bimmers, arsenic good as other brands' products, pinch powerfulness outputs ranging from mundane to mega.

Having made its debut successful 2009, nan ZF portion is some lighter and simpler than nan Aisin, which lends to faster shifts. The AA80E weighs 209 pounds, whereas nan 8HP weighs 176. As pointed retired by FCP Euro, only 3 of 5 full displacement elements are utilized successful immoderate gear, which cuts down connected resistance and bolsters smoothness. By comparison, nan Aisin's machine has to actuate four. While ZF 8HP displacement times are programmed by immoderate automakers to beryllium astir 200 milliseconds, capacity models' alteration betwixt 50 and 150 milliseconds. The Aisin's 100-millisecond minimum displacement clip puts it right successful nan middle of that range. Fast, but not arsenic accelerated arsenic nan ZF tin be.

In position of selecting which is better, it really comes down to individual preference. Not only successful regards to one's desired displacement times, but besides really they feel. This writer has knowledgeable some successful a myriad of vehicles, and while nan Aisin is simply a hairsbreadth slower, it's not capable to wholly constitute off. Both transmissions are regarded arsenic reliable arsenic agelong arsenic they spot regular work and don't woody pinch much powerfulness than they're designed for. Perhaps astir importantly, they some decidedly put nan aged slushbox connotation to bed.