Toyota's shift logic engineer should be shot

[RedSled]

The extra torque multiplication of additional gears would keep the motor from having to work so hard and consume fuel like it does. A well geared 6+ speed auto and direct fuel injection would improve mpgs of the 4runner 20%+ and improve acceleration as well. It would also help find a better gear ratio on inclines and keep from increasing rpms by over 1,000rpms on a single gear downshift.

Toyota is ultra conservative and runs their models into the ground before making a drivetrain change. That is especially the case with their trucks. The only thing that really keeps them in the game is their reliability, especially with the Tacoma and 4runner. It is certainly not their drivetrain performance or amenities.

I love the simplicity and reliability of the 4runner, but damn, they could have updated the drivetrain at least once between 2010 and now and made their trucks even more desirable and competitive. Everyone, and I mean everyone, updates their drivetrains every 3 to 5 years.

The reason they update every 5 yrs is because they keep having warranty work on them, and they can’t keep them on the road. This is just me, but i have no problem with this tranny, i shift when i need to and enjoy the probability that my trans. Is going to get me home.

 

[justanothereric]

I love the simplicity and reliability of the 4runner, but damn, they could have updated the drivetrain at least once between 2010 and now and made their trucks even more desirable and competitive. Everyone, and I mean everyone, updates their drivetrains every 3 to 5 years.

I most definitely agree with this. "If it ain't broke, don't fix it," can only be used for so long. 10 years maintaining the same powertrain in an industry where technology is advancing so quickly across the entire board amongst manufactures is not going to cut it. Ye,t I purchased a 2021 4Runner and have the same complaint as OP. so LOL.

My transmission consistently hunts between 4th and 5th ESPCIALLY when I'm using the adaptive cruise control and the incline grade slightly changes.

Does anyone know if there's a way to use the cruise control without it being dynamic and adjusting speed/distance? I just want an old school locked speed cruise control..

 

[02SE]

The extra torque multiplication of additional gears would keep the motor from having to work so hard and consume fuel like it does. A well geared 6+ speed auto and direct fuel injection would improve mpgs of the 4runner 20%+ and improve acceleration as well. It would also help find a better gear ratio on inclines and keep from increasing rpms by over 1,000rpms on a single gear downshift.

Toyota is ultra conservative and runs their models into the ground before making a drivetrain change. That is especially the case with their trucks. The only thing that really keeps them in the game is their reliability, especially with the Tacoma and 4runner. It is certainly not their drivetrain performance or amenities.

I love the simplicity and reliability of the 4runner, but damn, they could have updated the drivetrain at least once between 2010 and now and made their trucks even more desirable and competitive. Everyone, and I mean everyone, updates their drivetrains every 3 to 5 years.

True, more gears means the potential for a better ratio for any given situation.

However, my point was that if the 5 speed auto and a 10 speed auto have the same overall ratio in their highest gear, and the same engine providing the power, both will downshift to get the engine RPM up to where the engine can maintain speed on a grade, against a headwind, higher speeds, or all of the above.

We have several grossly overpowered vehicles that can maintain speed in top gear on any highway. They are lots of fun for what they are.

The 4Runner is not overpowered, and makes due with it's 5 speed A750F transmission. Why I have it is because it's a great 4wd trail vehicle, and it's track record of reliability.

 

[gbarr]

I most definitely agree with this. "If it ain't broke, don't fix it," can only be used for so long. 10 years maintaining the same powertrain in an industry where technology is advancing so quickly across the entire board amongst manufactures is not going to cut it. Ye,t I purchased a 2021 4Runner and have the same complaint as OP. so LOL.

My transmission consistently hunts between 4th and 5th ESPCIALLY when I'm using the adaptive cruise control and the incline grade slightly changes.

Does anyone know if there's a way to use the cruise control without it being dynamic and adjusting speed/distance? I just want an old school locked speed cruise control..

I have owned 3 4Runners, an 04 V8 4wd, 14 v6 4wd and 17v6 4wd, al three acted as discribed on the highway in hilly country i.e. always hunting between 4th an5th and not wanting to shift back to 5th when they should. That said, not sure if new 4 Runners work like my wifes 19 Highlander v6 but with it if you hold in the cc button in for 5 seconds magically you are in reg old cruise control not The assisted kind that brakes for you or keeps a constant distance relative to the car in front of you, maybe this helps maybe not.

 

[Charles Bronson]

Why I have it is because it's a great 4wd trail vehicle, and it's track record of reliability.

All very true. It's basically like a hammer. Simple and effective. The 4runner, Tacoma, and Land Cruiser have a reputation to keep and when you're in the middle of nowhere on the trails, these are the trucks you want for sure.

 

[Charles Bronson]

My transmission consistently hunts between 4th and 5th ESPCIALLY when I'm using the adaptive cruise control and the incline grade slightly changes.

Does anyone know if there's a way to use the cruise control without it being dynamic and adjusting speed/distance? I just want an old school locked speed cruise control..

You can turn the adaptive (radar) cruise control off and have normal cruise control.

When in the cruise control, I had the radar reduced to it's lowest setting. It hunted even when there weren't cars in front. I never thought to shut it off adaptive cruise control completely to see if it made a difference.

For the life me, I can't figure out what data the ECU-trans ECU would be seeing to make them behave differently with respect to downshifts and torque converter unlock when cruise is and isn't engaged. Perhaps it's tied to the electronic throttle and how the ECU-trans ECU are asking to maintain speed, perhaps with more throttle aggressiveness. It doesn't matter, clearly Toyota won't fix it after 10+ years

 

[jp.vegas]

You can turn the adaptive (radar) cruise control off and have normal cruise control.

When in the cruise control, I had the radar reduced to it's lowest setting. It hunted even when there weren't cars in front. I never thought to shut it off adaptive cruise control completely to see if it made a difference.

For the life me, I can't figure out what data the ECU-trans ECU would be seeing to make them behave differently with respect to downshifts and torque converter unlock when cruise is and isn't engaged. Perhaps it's tied to the electronic throttle and how the ECU-trans ECU are asking to maintain speed, perhaps with more throttle aggressiveness. It doesn't matter, clearly Toyota won't fix it after 10+ years

It's way more than 10 years. This powertrain dates back to the 4th gen 4Runner rolled out in 2003. There are minimal differences with the VVT as compared to the 4th gen motor but the transmission is the same (as is most of the chassis and drivetrain). Clearly not a bad thing from a reliability standpoint but my point is Toyota has been milking this combo for a lot longer than the 5th gen has been rolling.

 

[RichinRidgewood]

We've owned our 2020 ORP since July. Yesterday we drove 200 miles to Wichita which was through a constant 20mph+ headwind and lots of very long and steep hills through the Flint Hills of south central Kansas. The 4runner was constantly bouncing between 5th and 4th. Then when you'd get past the grade, it took forever to upshift to 5th. I could remedy this with a simple tap of the accelerator to force the upshift. The truck only managed 16mpg too. LOL Towards the end of trip I learned the key was to keep it under 78mph and when in cruise control, give it a little throttle myself going up hills to unlock the torque converter in 5th gear to keep it from downshifting to 4th.

Whoever at Toyota did the shift logic should be shot. It is seriously bad in those situations. There is no need for a downshift into 4th. Simply unlocking the torque converter in 5th is enough for those types of grades. It's as if the trans ecu doesn't recognize that 5th gear torque converter unlock is an option. I tried also using the manual mode function with it in 5th but it didn't help.

For those that have throttle enhancers like the Sprint Booster, does your 4runner exhibit this annoying behavior?

facepalm

 

[justanothereric]

You can turn the adaptive (radar) cruise control off and have normal cruise control.

Do you happen to know how?

 

[Whippersnapper02]

Do you happen to know how?

Page 281 of the manual that no one reads.

 

[PhillySilver]

Not much to add to the points that OP raised other than to say that my 2020 ORP does a little hunting on hills but nothing super annoying.

If you want to see super annoying, stop by sometime and I will let you drive my Acura TL SH-AWD. That thing has the worst transmission / shift points of any car I have ever owned. It is in 5th gear by the time you are doing 25mph and hunts like nothing I have ever seen in the 30-40 range which is where I spend most of my time on my daily commute in Philly traffic. Most reliable but also the most annoying / least pleasurable to drive of any car I have ever owned.

 

[Charles Bronson]

It's way more than 10 years. This powertrain dates back to the 4th gen 4Runner rolled out in 2003. There are minimal differences with the VVT as compared to the 4th gen motor but the transmission is the same (as is most of the chassis and drivetrain). Clearly not a bad thing from a reliability standpoint but my point is Toyota has been milking this combo for a lot longer than the 5th gen has been rolling.

Wow, I had no idea. I knew the 5AT had to be old because it behaves EXACTLY like my 5AT from my 2003 Infiniti G35. The "sequential" mode between the G35 and 4runner are the same including the upshift/downshift directions and the fact that they are essentially top gear limiters, and when in sequential mode, there is more of delay to get the transmission to downshift with the throttle. It's all very familiar to me, but quite old school.

Funny how Toyota has changed over the years. Back in the 1980s and 1990s, they were often class-leading with powertrain technology. Now they're largely the brand of old folks who value reliability and simplicity over everything else. Toyota played it so safe with the new Supra that it's entirely a BMW under a Toyota skin. Even the steering wheel, minus the airbag cover, is made by BMW LOL

 

[BlackWorksInc]

It's way more than 10 years. This powertrain dates back to the 4th gen 4Runner rolled out in 2003. There are minimal differences with the VVT as compared to the 4th gen motor but the transmission is the same (as is most of the chassis and drivetrain). Clearly not a bad thing from a reliability standpoint but my point is Toyota has been milking this combo for a lot longer than the 5th gen has been rolling.

The basic structure of the 1GR-FE and A750E/A750F transmissions is the same as the 4th gen, but they're very much updated over the course of a decade. This is something Toyota is notorious for, incremential updates and improvements without any fanfare. For example the '03~'05-ish 1GR-FEs are relatively similar, but also incompatible with the newer '06~'09 units because things like cam sensors were changed from 2 wire to three wire, small components were changed/improved, etc.

The '10+ 1GR-FE is similar in block design, but the timing cover and heads are very different due to going for a dual VVTi system and a thinner viscosity oil; there's very little that is compatible with prior 1GR-FEs and a lot that was re-designed (hell if I recall correctly I thing a T4R or T120 forum member actually got the engineers to redesign the 5th gen heads to drain oil better at steep angles because their new 5t gen stalled at MOAB or something like that IIRC). Same thing with the A750 transmission, a '10+ isn't the same as a prior model internally. Of course none of these changes are really charted anywhere specifically, you'll find some information dotted here and there, but there's no real chart of every little change made to the 1GR-FE, hell they don't even bother to differentiate the 1GR-FE from the pre-Dual VVTi years with the current 1GR-FE (which was mildly confusing for some people when we still sold the Tacoma with the non-Dual VVTi 1GR-FE.)

In any case, I whole-heartedly agree with the OP here; I really hate whoever programs the logic for the ECM & ECT in Toyota's modern trucks and SUVs. They seem to prioritize EPA/MPG numbers so that there's only one "right" way to drive these vehicles, like a Prius. The programming seems centered around this ideology starting with the numb 5th gen accelerator pedal toe-in that makes it slower off the line compared to a "lesser" 4th gen V6, all the way up to some of the odd coasting/cruising behaviour in it's shift choices. If you really want to see the pinnacle of these drivetrain programmer's "skill" look no further than the 3rd Gen Tacoma's neutered drivetrain. That thing has had more updates for it's shift logic than I can recall for any Toyota made in the last decade or two.

This is basically them focusing on turning everything into a Prius and chasing the MPG numbers at the cost of everything else, Toyota's new "design goal" I suppose...

Wow, I had no idea. I knew the 5AT had to be old because it behaves EXACTLY like my 5AT from my 2003 Infiniti G35. The "sequential" mode between the G35 and 4runner are the same including the upshift/downshift directions and the fact that they are essentially top gear limiters, and when in sequential mode, there is more of delay to get the transmission to downshift with the throttle. It's all very familiar to me, but quite old school.

Funny how Toyota has changed over the years. Back in the 1980s and 1990s, they were often class-leading with powertrain technology. Now they're largely the brand of old folks who value reliability and simplicity over everything else. Toyota played it so safe with the new Supra that it's entirely a BMW under a Toyota skin. Even the steering wheel, minus the airbag cover, is made by BMW LOL

Toyota hasn't made a Supra since the 2000's, they do sell a BMW Z3 with cute Toyota Badges on it. They aren't interested in producing performance vehicles for the public anymore, even Lexus is still conflicted in it's desire to provide a luxury performance vehicle if you look at their models. The internal communication of Toyota or lack there of is just astounding, it's such a different company than it was 20, even 10 years ago.

 

[Charles Bronson]

Page 281 of the manual that no one reads.

Last night I went out and tested to see if the 4runner would behave any differently in "normal" cruise control mode while going up long and fairly step highway grades at around 79-80mph. Wind wasn't bad either.

She'll still grab 4th about 1/2-3/4 way up. Damn. Turn the cruise off and use my foot to maintain speed and it doesn't downshift going up the same stretch. So frustrating. I guess I'm just going to have to learn to not use cruise control when driving in areas with any real grade and/or wind.

Funny that we've owned this truck since late July and last weekend was my first road trip in it. My wife and kids had already done couple longer trips and thought the shifting was normal. Now I totally get what people mean by Toyota gear hunting. Old news :whipping2

 

[Charles Bronson]

Toyota hasn't made a Supra since the 2000's, they do sell a BMW Z3 with cute Toyota Badges on it. They aren't interested in producing performance vehicles for the public anymore, even Lexus is still conflicted in it's desire to provide a luxury performance vehicle if you look at their models. The internal communication of Toyota or lack there of is just astounding, it's such a different company than it was 20, even 10 years ago.

All so true. What I find so funny is that so many of the Toyota and Lexus models have very aggressive styling (often times over styled) and that styling doesn't match the drivetrain or the chassis performance. Toyota over styled the hell out of the new Supra with all the fake vents, spates, and winglets. It would be a beautiful car without all that crap. I do have to admit that I'm excited about the upcoming IS500 with the 472hp 5.0 V8. I'll likely pick up a used one to replace my much loved and shocking reliable BMW M235 6MT. But first, I need to find a 2002-2004 Corvette Z06 for my weekend/track car.

 

[Whippersnapper02]

Last night I went out and tested to see if the 4runner would behave any differently in "normal" cruise control mode while going up long and fairly step highway grades at around 79-80mph. Wind wasn't bad either.

She'll still grab 4th about 1/2-3/4 way up. Damn. Turn the cruise off and use my foot to maintain speed and it doesn't downshift going up the same stretch. So frustrating. I guess I'm just going to have to learn to not use cruise control when driving in areas with any real grade and/or wind.

Funny that we've owned this truck since late July and last weekend was my first road trip in it. My wife and kids had already done couple longer trips and thought the shifting was normal. Now I totally get what people mean by Toyota gear hunting. Old news :whipping2

Could just be the convertor unlocking. In my Tacoma before the supercharger the ECU decided a 2 gear downshift was needed for a slight grade. Ever since turned off the cruise in hilly areas. After the supercharger it wasn't an issue.

More gears just means more shifting. 10 speed must be fun.

 

[AMLOR]

RE GEAR! for the win

The solution to all of this is to get the engine running up in the torque band.
I re geared recently to 4.88's with 33's.
The difference is amazing. All of the shifty gear hunting is gone...(Ok almost all of it) 85%+ reduction while at highway speeds.
Around town...you no longer need a Pedal Commander.

The engine is now running about 2625rpm at 70. About 600 rpm further up into the torque band. That is about the sweet spot for mine. (Remember that aerodynamic resistance increases at the cube of speed...so 40 to 80 isn't double the air resistance, it's triple.)

Just under 5700lbs fully loaded with passengers. Netted 15.25 overall on the highway over about 1500 miles running 70.
Offroad the now, 44.20:1 low range crawl ratio made short work of Big Bend NP and Big Bend Ranch SP off road High Clearance, 4X4 required trails.

The mileage sucks on 4Runners anyway. A couple of miles per gallon overall is a small price to pay for the significantly improved drive-ability.
And at less than 1/2 the price of a Super Charger with none of the potential complications.