the pics are from the internet, very similar to the ones I'm looking at

The thing is that it ain't really going only with my heart.
The Vitara also seems to be also a solid choice...

Matter of fact, I own a 2003 Chevy Tracker (Suzuki Vitara) and aside from replacing the timing chain at 120,000 miles, the car has been perfect.  It was made in Canada, for what it's worth.

My previous experience with the reliability on the Suzuki Grand Vitara and later the Suzuki S-Cross have been really positive. I really doubt that the 2017 models are that much worse then 2014 and 2008 models...

On their older models the Achilles heel definitely was transmissions.
But the new ones have the TG-70/71/72/73SC transmission from Aisin.
That's a very proven design, originally developed for Diesel PSA products (Peugeot Société Anonyme = Peugoet public limited company) to replace the troublesome Renault DP0, and later used on many Volvo diesels and these transmissions often easily lasted for over 200k miles.

Well I don’t know about you, but my chapter with Suzuki has all but ended. The era before 2010 was when they were making simple but robust cars, now I don’t trust them to holdup post 10yrs. I still see old GVs & SX4 sedans on the road. Where are the ones sold near you, being manufactured?

The ones I checked the registration on were made in Hungary with their first VIN digits (TSM) pointing the Esztergom plant.
Did Suzuki quality went downhill? imo the new ones feel great. The interior isn't as nice as a Toyota or even a Kia but the mechanical components seem great...

Maybe the guys in Hungary are building better Suzukis than the ones made for other parts of the world.. when I say quality, I mean the build quality. For reliability, yeah, their small engines are still quite good. I’ve yet to see a luxurious interior in any Suzuki vehicle. It’s always been utilitarian, from what I’ve seen. Again, maybe in Hungary they’re using good suppliers?

Well, it’s really not the case in my opinion, what really matters is the make and model.
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It’s really not about how reliable each mechanism can be, it’s imo about how early is it engineered to fail.
Like how the “next gen” AISIN TG-80SC has a filter that’s almost impossible to replace, how they began not even bothering having a dipstick, and also how the ATF change procedure became impossibly complicated often requiring special tools.
… It’s not like they couldn’t resolve all of these issues that make servicing it impossible, they just actually do not care one bit about the consumer.
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Generally, the AISIN TG-70SC series and the Mazda SkyDrive both have 6 speeds and are as reliable as modern-ish automatics get.
And there are plenty of transmissions less reliable then that with less gears, DP0, 4F44E…

right, but the more parts and complexity it has, the more opportunity there is for bad design, mistakes, defects, and failures (engineered or otherwise)

Well, The parts that get added when increasing the amount of gears are usually frictions, drums, and actual planetary gears. But, about 85% of the issues are with the valve body and solenoids, this part of the design doesn't change much.
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Here's a Hyundai 8 speed

Heres a Hyundai 4 speed

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The valve body and solenoids aren't that different between an early 2000s simple 4 speed and the brand new 8 speed (that they're just starting to use on the newer models). There are additional solenoids but these are usually not the ones that cause trouble.
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There are more opportunities for a design mistake, but companies like Aisin rarely make those. Usually it's just built to wear out completely and not break in one specific part.
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As a matter of fact the new 8 speed transmissions from Hyundai-Kia(A8LR1 / A8MF1) are surprisingly reliable despite them being very complex.
(There are accouple of known issues (some seem like genuine design mistakes) but if the transmission is serviced properly (ATF change every 35k miles) and the first model years are avoided they seem to be great)

More speeds means you have to now add more solenoids, more valves and body channels, more electronics and more software to control them right?

It’s not a “P1xP2” probability,
it’s more of a bell curve while the only thing that increases (with the addition of parts) is the standard divination getting larger.
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The thing is that it’s not that each mile you drive you have a set P(x) chance of it failing, it’s a bell curve for each part.
It is how these overlap, and where the mean point lands that defines how reliable it will be.

It's P1 + P2 probability

It’s really not linear though

if a solenoids have 1/1,000 probability of failing in x km (p=0.001) then ...
if you have 2 solenoids, the chance of tranny failure is 2/1,000
3 solenoids = 3/1,000 etc...
isn't that linear?

Cause it’s as simple as
P(failure at 5k miles) ≠ P(failure at 150k miles) so it’s not multiplied.
It’s a bell curve with very low standard divination - so the chance of something failing at early mileage is ≈0 so the sum of the P(x) ≈ 0.
And P(150k miles > x > 200k miles) ≈ 1 so you so it doesn’t matter that there are more parts, it doesn’t change the probabilities.
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What it can change is P(100k miles > x > 150k miles) make the probably of an issue SLIGHTLY increase because the divination on these is as low as it gets.
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When we know that the deviation is low and the mean is the same for all of them… it really don’t matter how many you have.
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Simplicity ≠ reliability and not the opposite. Modern manufacturers really nailed down the “it will fail at X miles +/- 20k”

It absolutely matters how many you have. The transmission depends on ALL of the parts working.

yes, I completely understand that failure probability isn't constant over time. It has nothing to do with the fact that more parts increases probability. The area under the normal distribution curve between 0 and 100k miles for example, is a fixed number, and you multiply that number for each additional event. These are the rules for how probability works.

It's also great that they can predict failure to such high accuracy (low standard deviation). What is your point? It simply means that you can predict the failure of 2 or 3 or more solenoids also with high accuracy.

Let me give you an example that anybody can understand ...
When I flip a coin there's a 50% chance of getting a head. If I throw a pocket full of coins on the ground, the chance of getting one head is going to be very close to 100%
Don't let the manufacturer's marketing blah blah confuse you.

That’s not how it works. Your car doesn’t have the same chance to brake at 5 miles and 150k miles so it’s not a coin flip stenario.
Look up “ Normal distribution”, the “Cumulative distribution function” is what represent the chance is a mechanical components has broke.
I wasn’t the best student in collage when it comes to statistics theory but to me it is obvious that adding more parts with modern manufacturing doesn’t impact long-term reliability in a significant way.
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What matters isn’t the gear amount but the quality, both this Aisin and the SkyDrive don’t have reliability issues at all.
For the SkyDrive it’s a central bearing that can fail but you can hear it when it does.
On this specific Aisin the issue is that on higher torque diesels the frictions (small clutch discs) wear out after 150k miles and the transmission begins to slip.
None of these failures are related to their Mechanical complexity - on either of these the chance that something other then what I’ve described happens is ≈0.
P(random part failing) + (random part failing) = ~0 + ~0 ≈ 0.

It is how it works. The coin represents the probability of a part failing before some threshold. 150k miles for example.
I know what normal means. The type of distribution, and the mileage, is absolutely irrelevant to the principle of compound probability.

Mechanical complexity absolutely increases chance of failure. That means for more complex machines, each of your parts need to be made to tighter specifications.

Clutch discs are a bit different because the transmission can keep going if one disc wears out.
But we can do a real world example. Instead lets consider gears. A 4sp auto has two planetary stages. A 10sp has four.
Lets say they are 4 pinion planets, so 8 and 16 pinions, respectively.

Now let us assume that the probability of one pinion failing by 150k miles is 1/10 (fictional for the sake of argument)
When one pinion fails, steel shards go everywhere and transmission goes boom.
The probability that a pinion fails (and thus transmission) before 150k miles is
4sp = 57%
10sp = 65%
(and please do verify this. There are various online calculators)

In your example, crappy clutches may mask this effect, but it's still there. And the probabilities of the pinions (or solenoids etc.) is still GREATER than zero for the interval between 0miles and clutch failure. And that probability is higher the more complexity there is in the chain.

By that logic the worst would be Toyota 4 speed transmissions. So many parts! So many control systems! A modern 8 speed doesn’t even come close.
And the best would be early Fiat and Renault transmissions for their simplicity.
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Toyota is an example how more parts can corollate to better reliability, their well built early 2010 cars aren’t simple at all compared to a Hyundai.
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It’s now how many parts there are it’s how it’s made. The part count has pretty much 0 impact.
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It’s not about it breaking it’s about accumulated wear and the chance. And both these 6 speeds are more reliable then any even semi-modern transmissions.
These parts aren’t hand made; ya don’t see transmission coming into the shop with a defect you haven’t seen before - all of them wear out exactly the same for each model.

wait, you're saying a modern Toyota 8 speed has less parts and complexity than their 4 speed? I find that surprising. I mean, unless they switched to a completely different design.

You're right that probabilities are not the whole picture, and I do agree with you on some level that complexity does sometimes improve reliability, but it is subject to diminishing returns. For example liquid cooling was an improvement on the air cooled engine by allowing it to produce more power and work harder and longer, at the cost of some additional maintenance. There are plenty of examples of over-engineering. Cylinder deactivation, automatic seatbelts , BMW dual series cooling fans .... the KISS principle is real. Sometimes it takes a while for manufacturing technology to catch up design complexity.

And yes, of course overall design and quality is an important factor.

The Asian 8 speed (a transmission I don’t recommend because it’s EAT8 and F35 variants wear out typically before 150k miles, and due to how hard it is to service some of its variants) is a very simple gearbox. It’s about as complex and has as many parts as some 3 speeds.
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I had some trouble finding a good schematic of a Toyota 4 speed, so I chose a GM 5 speed.
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Here’s the GM 5L40E, an old school 5 speed transmission

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And here’s an AISIN TG-81SC 8 speed

Thank you this is very interesting. Aisin achieved this size reduction by using a more complex "Ravigneaux Planetary Gear Set" which essentially squashes two planetary gear sets into one. (your diagram does not explode this assembly. If it did, you would see a few more parts). That's very clever, but it also makes the pinions smaller. I wonder how much that reduces the torque rating.

https://www.youtube.com/watch?v=Ehgwf_C5zgY
https://www.youtube.com/watch?v=7iTn8OWxVFU

@MountainManJoe
So does the GM 5 speed. Literally everyone uses Ravigneaux gearsets.
That's what you'd find in a 1950's Ford Cruise-O-Matic.

As far as the torque rating? it's Aisin's it's a high torque capacity gearbox. the "F35" variant is rated to 350NM while the EAT8/F45/G45 variants are rated to 480NM.
It uses the technology from the TF-80SC, which uses it's technology from the TF-60SN. - both of these where weak IMO. one the weak spot on Volvos and the other making Volkswagen owners lives even worse - but the newer 8 speed variants seem to be not too terrible, much better then the old ones.

As far as the torque rating, it's Aisin's high torque capacity gearbox. the "F35" variant is rated to 350NM while the EAT8/F45/G45 variants are rated to 480NM.

(It's used on the new Highlander, Sienna, high end Volvos, Cadilac XT5, VW minibuses,...)

It uses the technology from the TF-80SC, which uses it's technology from the TF-60SN. - both of these where weak IMO. one the weak spot on Volvos and the other was making Volkswagen owners lives even worse - but the newer 8 speed variants seem to be not too terrible, much better then the old ones.

hm. must be a euro thing. I've never seen it on N.A. transmissions. Then again, I don't strip down trannies for a living. Thanks for the knowledge.

Almost all transmission with more then 4 speeds are Ravigneaux, achieving 4 speeds with a Simpson would require 3 separate gearsets.
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The hottest thing in transmission design is probably Lepelletier gearsets - offering six forward gears and reverse using only 2 gearsets.
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That’s the reason why the old Aisins with only five speed had like 7 clutch packs, but the new ones with eight speeds have only 4 clutch packs and less gearsets 👀
(It’s a junkyard’s channel, I’ve never seen anyone have as much knowledge in mechanics. it’s an old video so they don’t have proper translated subtitles)
https://youtu.be/8BfLt9hma1Q
Just look at the mess inside of this somewhat unreliable and complex Aisin 5 speed.
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(This one already does have subtitles)
https://youtu.be/_nJ6AwE2FV0
The 6 speed variant that replaced it is so much simpler but it also didn’t last too long…
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So yeah… more gears can equal less parts. And sometimes more parts equals better reliability.
That’s why transmissions should be judged on an individual basis.
Like how the Aisin TF-80SC is Medicare, the Aisin TF-70SC is great and the Aisin TF-60SN is total trash. (All of them are very similar but their reliability can go between “50k miles if you don’t clean your radiator” to “200k miles before having to simply replace frictions”)

I've never owned anything with more than 4 gears. Later models of my Savana have the 6L80 (1 Ravi + 1 simple)...
or the 8L90 and later 10L90: 4 gearsets all simple. It claims to be more efficient, lighter and fits in the same space as 6L80. but it looks like a beast. 8L90 is now the subject of lawsuits.

So here's a question for you: the Ravigneaux has been around since 1949... why did we only just start using it so much recently?

Ford claims to have been using it since the 50s. But I actually do not know, that’s a question for a mechanical engineer…
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Personally all my cars have either 5 or 6 speeds, all of them use a clutch and mechanical gears.
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Including the hilariously bad and unreliable ‘08 Toyota “automatic” 5 speed motorized manual transmission (MMT)
It’s just a hydraulic, and 2 electric actuators strapped to a 1980s Corolla manual gearbox.
It shifts poorly, it’s known for everything in it failing (the clutch lasts about 40k miles on average, mechanical components are known to fail, and it was the subject of multiple recalls) and it just drives hilariously bad (it’s like someone is learning to drive a manual, it doesn’t like to downshift on its own, it tends to take about a second to start from a standstill (sometimes it fails to shift into first / reverse and just doesn’t begin moving - according to Toyota that’s completely normal), and on hills it always rolls backwards)
But I love it, it’s worthless so I can just keep it as a backup car and it just has the most mechanical sounds and feeling ever…

sounds like the '03 Golf my friend had (some kind of DCT I think).
When you shifted into 'D' and let go of the brake it would start rolling backwards indefinitely, until you pushed the accelerator. It shifted poorly too.

Yep it seems so, the early VW DSG (DCTs) we’re total trash… I’m surprised it is still driving.
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But to be fully honest even the DCT in my Volvo (MPS6) still has a tendency to roll back a very small amount from a hill… (the ABS and BCM modules have a lot of error codes about faulty communication so its properly that)
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DCT and AMTs are super weird… In all these years I found only one well built model I like driving - the PSA EGS6 “Robotic” just works although people are complaining that it feels “lazy” in 1st and 2nd…
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But on a family member’s 2021 Kia Niro I’ve been driving very recently the DCT is quite good in sports mode (in Eco it’s jerky) and when it feels like it’s about to slam hard into gear - it just goes into EV mode and restarts the engine.
It’s really bizarre, when using the “semi-autonomous” mode and switching lanes it starts the gas engine when it’s clear to change lane and shuts it down immediately after changing (the engine in general works in bursts of 10-30 seconds or sometimes for a minute or two when it’s charging the battery)
it does 56-73mpg Highway according to it’s screen. The lowest I’ve seen if get was 42mpg…

I think we have got to the point where spending an extra 3 grand over a base model Corolla for a hybrid is actually worth it? (Although it’s a Kia) this car seems to be reliable and the 10 year / 100k mile warranty means that it’s perfect for someone who doesn’t drive much.
Here it’s reporting an average of 3.9L/100KM over the last 2,000 miles. (= 60.3 US MPG = 72.5 British MPG) and it does seem to match how much fuel I put in it and comparing it to the odometer…

my commute consists both of a highway drive at 70mph and stop and go traffic. So the ideal gearbox that would still offer dynamic driving and economy would be a "5+E" configuration.
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Non-conventional automatics such as CVTs, DCTs and AMTs usually struggle with stop and go traffic. I drove a 4 speed automatic for quite a while and it just always felt as if it's not in the correct gear.
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I live in a place where the roads are very congested so having a gearbox that can both be reasonably swift to start and economical at speed is very desirable.