Gear hunting while in cruise control is "Character" per Toyota

[Charles Bronson]

My wife had a free 15K service for her 2020 4Runner ORP. I had her ask the service advisor if there was any TCM or ECU reprogram available for highway gear hunting, specifically when cruise control is engaged (either radar sensing on or radar sensing turned off). Our 4runner can hunt between 4th and 5th gear when going up moderate consistent inclines over a longer distance (1/2 mile or greater) when speeds of 70mph or greater. FYI, speed limits around us are 70 to 75mph and most are doing 80+. The issue appears more often when head and/or cross winds are stiff (i.e., 15-25mph) which is very common for the Midwest.

The service advisor chuckled and told my wife it has been an issue reported by many 5th gen owners for years now (I knew this). He said there is still no fix and that Toyota has told him specifically that the hunting is just "character" of the 4runner and owners need to live with it.

What is so annoying is that if I turn off CC, our 4runner will climb the hill, rarely without even downshifting! But turn CC back on and it will downshift to 4th and sometimes go into a gear hunting fit. It is super annoying because Midwest is full of long rolling hills and heavy wind so this issue occurs often. It is clearly a TCM programming thing related to vacuum/load while in CC. This is something that can be easily fixed with basic programming but Toyota is just too damn lazy to address it.

Side note, our 4runner gets better mpgs driving in 4th at speeds below 65mph when in rolling hills. LOL

 

[honda250xtitan]

so leave it in cruise control and take it out of drive and put it in 4th

 

[mocat16]

i thought this thread was going to be about the dangerous activity of shopping for gear / mods on your phone while driving in cruise control

 

[Forgetful]

I absolutely loathe cruise control on these vehicles, especially since this is my first automatic transmission. I'd pay an extra couple $$$$ for a manual trans in this vehicle like my 3rd gen...

 

[jrandom]

so leave it in cruise control and take it out of drive and put it in 4th

This :thumb:

 

[2021nightshade4x4]

It’s “characteristic” of an underpowered engine connected to a 5 speed transmission.

There - I fixed it.


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[03_4x4Runner]

It’s “characteristic” of an underpowered engine connected to a 5 speed transmission.

There - I fixed it.


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This pretty much sums it up. In any kind of hilly terrain on the highway I just put it in 4. On long steep mountain grades it will kick down to 3rd and run about 4500-5000 rpm. It sounds terrible. Eventually I just take the cruise off and slow down and let the other vehicles pass me. There has been many times after the road levels out that I forget to put it back into 5.

 

[barry581]

Let's see.... A Camry, 3 Tundra's, 2 Highlander's, 2 Rav4's AND my 2021 4Runner all "hunt" while in cruise control. The 2007 Tundra was the worse, by a good measure, than the others. The only Toyota's I haven't had the issue with had manual transmissions.

 

[DAW89446]

My ‘18 does the same. What’s even more aggrevating is that it stays in 4th long after topping the hill or even descending.

 

[2021nightshade4x4]

Gear hunting while in cruise control is "Character" per Toyota

Let's see.... A Camry, 3 Tundra's, 2 Highlander's, 2 Rav4's AND my 2021 4Runner all "hunt" while in cruise control. The 2007 Tundra was the worse, by a good measure, than the others. The only Toyota's I haven't had the issue with had manual transmissions.

So you’re telling me I have no reason to feel like I’m missing out by not getting a Tundra, Sequoia, or Land Cruiser?

As much as I HATE ZF transmissions for their (lack of) reliability, and love my Toyota, I think this is precisely why they elect to have theirs lockup in every gear.

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[2021nightshade4x4]

Gear hunting while in cruise control is "Character" per Toyota

- Duplicate post -

 

[Sp00ner]

I watched the behavior on my head unit that can display a bunch of parameters on the way to Colorado and back. While his statement might be said better, he's pretty much right.

I mean, you can watch it start to apply throttle without shifting until engine load hits 100% and then it downshifts. Then it starts backing off throttle till it stops accelerating, which leaves the RPMs too high so it upshifts.

That's pretty much the behavior you get with any car that doesnt have an excess of power down low, though when you're rocking an 8 or 10 speed modern transmission or a (shudder) CVT, you dont have nearly the jump in gear ratios to notice it.

 

[2021nightshade4x4]

I watched the behavior on my head unit that can display a bunch of parameters on the way to Colorado and back. While his statement might be said better, he's pretty much right.

I mean, you can watch it start to apply throttle without shifting until engine load hits 100% and then it downshifts. Then it starts backing off throttle till it stops accelerating, which leaves the RPMs too high so it upshifts.

That's pretty much the behavior you get with any car that doesnt have an excess of power down low, though when you're rocking an 8 or 10 speed modern transmission or a (shudder) CVT, you dont have nearly the jump in gear ratios to notice it.

Specifically what I mean is something, somehow needs to be present to keep that load going uphill without NECESSARILY downshifting. It can be done with a powerful enough engine (high compression or forced induction and a fuel that can withstand substantial timing advance). Lockup in the transmission in every gear helps, but I admit the enormous trade off is torque converter wear and the lockup clutch being cycled so much. Maybe Toyota discussed that and just said NO.

I have a good vehicle to compare it to, but it’s night and day, apples and elephants. My notoriously unreliable 2012 Range Rover full size, last of the square body L322 with a 510 HP / 463 TQ supercharged engine as stock, then upgraded pulley and tune (do with that what you will, VelocityAP cites 645 HP / 630 TQ after tune, but I completely understand if there are reasons to doubt that).

The Rover just pulls uphill in 6th around 1400 RPM at 50 MPH or so without downshifting. If I run the same stretches of highway in the 4Runner it just won’t do it without kicking down. I don’t know if a premium tune would be enough to keep the 4Runner in motion without hunting. Pedal commander can help driving dynamics on flat surfaces, but like you said when that engine load maxes out, and you have nowhere to go, it’s shifting! LOL


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[TrailRunnin14]

About the only way to solve that issue is with a blower. Before that I just got used to shifting down to S4 before I encountered an incline.


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[2021nightshade4x4]

About the only way to solve that issue is with a blower. Before that I just got used to shifting down to S4 before I encountered an incline.


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Eager to see if anything comes out for the 2020+ models in the way of forced induction. It should get me somewhere around the power of an early 3rd generation Hemi, not quite 3UR-FE territory, which should be sufficient.


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[TrailRunnin14]

Eager to see if anything comes out for the 2020+ models in the way of forced induction. It should get me somewhere around the power of an early 3rd generation Hemi, not quite 3UR-FE territory, which should be sufficient.


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Magnuson says 355hp and 350tq. At 4800lbs, it’s no race car but it really helps with the smiles per gallon.


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[Sp00ner]

Specifically what I mean is something, somehow needs to be present to keep that load going uphill without NECESSARILY downshifting. It can be done with a powerful enough engine (high compression or forced induction and a fuel that can withstand substantial timing advance). Lockup in the transmission in every gear helps, but I admit the enormous trade off is torque converter wear and the lockup clutch being cycled so much. Maybe Toyota discussed that and just said NO.

I have a good vehicle to compare it to, but it’s night and day, apples and elephants. My notoriously unreliable 2012 Range Rover full size, last of the square body L322 with a 510 HP / 463 TQ supercharged engine as stock, then upgraded pulley and tune (do with that what you will, VelocityAP cites 645 HP / 630 TQ after tune, but I completely understand if there are reasons to doubt that).

The Rover just pulls uphill in 6th around 1400 RPM at 50 MPH or so without downshifting. If I run the same stretches of highway in the 4Runner it just won’t do it without kicking down. I don’t know if a premium tune would be enough to keep the 4Runner in motion without hunting. Pedal commander can help driving dynamics on flat surfaces, but like you said when that engine load maxes out, and you have nowhere to go, it’s shifting! LOL


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Sure, my Camaro was the same way, but as you said, it's apples to kumquats.

The 4Runner just doesn't have the capabilities to pull it off with 270hp and the aerodynamic profile of a bowling ball once you add gravity to the mix. The Camaro also got 33mpg at 85 mph while dynamically deactivating cylinders and an 8spd transmission, but I digress...

Going up from Denver to Breckenridge I had whole climbs being done in like 3rd gear at 4500 RPMs for pretty extended periods of time just to maintain 70mph, I literally laughed out loud more than a few times.

 

[Jeremy556]

About the only way to solve that issue is with a blower. Before that I just got used to shifting down to S4 before I encountered an incline.

4.56 or 4.88 gears on stock size tires will do it, too. 4runner should have 4.1 stock, IMHO.

 

[2021nightshade4x4]

Sure, my Camaro was the same way, but as you said, it's apples to kumquats.

The 4Runner just doesn't have the capabilities to pull it off with 270hp and the aerodynamic profile of a bowling ball once you add gravity to the mix. The Camaro also got 33mpg at 85 mph while dynamically deactivating cylinders and an 8spd transmission, but I digress...

Going up from Denver to Breckenridge I had whole climbs being done in like 3rd gear at 4500 RPMs for pretty extended periods of time just to maintain 70mph, I literally laughed out loud more than a few times.

Hate to hear outcomes like that - were you towing anything?

https://shop.ukrtrans.biz/wp-content/uploads/catalogs/A750E.pdf

Found out - Lockup clutch does operate in multiple gears, so we can strike that off the list.

Above link contains info on A750F (4WD) as well. Apparently the same trans found it’s way into some Tundras, too, behind the 4.7L V8. Those models are rated for 6700-8100 lb towing capacity, so I feel confident the trans is strong enough to handle added engine power to the 4.0L V6.

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[2021nightshade4x4]

4.56 or 4.88 gears on stock size tires will do it, too. 4runner should have 4.1 stock, IMHO.

Not to be a buzzkill, but wouldn’t that result in 5th gear then having the same effective ratio as 4th did with the original gears? We’d be quite literally BUZZING along down the interstate at 70 MPH turning 3100 RPM!


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