Cruise control problem

'24 4R won't maintain speed (80mph) when cruise is on. It's constantly shifting as it starts up even the slightest grade and it won't shift out when going down same grade. Doesn't do this when not on cruise. Toyota says this is normal but I no better because our '09 FJ doesn't have this problem. Help please.

 

This is pretty common especially with the TSS equipped newer Toyotas, which may be why your old one drives better.

I have noticed my CC is less intrusive and doesn't downshift as much and doesn't delay upshifting when I use the non radar CC mode. It's not 100% better but it's noticably better.

You can also try using S4 in hilly areas with CC on, it will shift less.

Even the non TSS models aren't awesome, the 5spd and 4.0 just don't do great with CC on anything but flat ground.

 

That sounds accurate to my experience with my 2021 Venture 4R. Probably my biggest/only complaint about the vehicle. I always set the cruise w/out the radar activated (holding cc on button for about 3 sec when activating). At 78 mph, any slight grade or even a decent headwind will cause downshift.

 

This is very normal. If you're going up any grade the engine needs more power to maintain the same speed, thus it hunts for another gear to help it. If you want to stop that, get your 4Runner tuned or re-geared and the gear hunting will stop.

 

I'll give the same advice as I did earlier - Just shift into S4 or S3 and stay there with hills. You paid for the whole tachometer, use the whole tachometer.

 

Agreed. RPMs won't hurt the engine. Case in point - I have a 2006 Scion xA with 230k miles that doesn't burn oil. That car runs 4000RPM at 80MPH.

 

Normal. The weight and aerodynamics really make it struggle on grades, requiring downshifts to increase RPM to maintain speed. The 4.0 makes most of its power at higher rpms.

On the downgrades it's still trying to maintain set speed, so it's not downshifting because the trans is engine braking. Shut the cruise off and it will immediately downshift.

I don't use the cruise in hilly situations or the mountains for this reason. I find it does much better when I anticipate the hills and increase speed to build some momentum before I hit them. A lot of times that allows it to make the hill without a downshift.

Nobody is excited about the new 4-cylinder, but I'm thinking it's going to be much better in this regard.

 

My '24 4R has a V6 4.0 engine with the same horsepower, torque and displacement as my '09 FJ, which makes me think there's something wrong with the CC. My wife and I can drive them by side and the 4R has a problem and the FJ doesn't.

And thank you very much to each of you for your reply. Hope you had a good Thanksgiving.

 

I think there can be a 600-800 pound difference in curb weight (4Runner heavier).

 

It feels like there's something wrong but there's not. All of our trucks do the same thing. Annoying, but you can rest easy.

The engine/trans won't act like that if cruise is not on. It'll still downshift and upshift but wont go back and forth like rapid fire.

 

Then why doesn't the FJ do it? I'm confused

 

Every 4Runner I’ve ever been in does this

 

Main reason is probably because the 4Runner is heavier than the FJ.
another reason could be they are tuned differently from factory (not sure if it’s true though). If you go with a tune like the OTT, it should help fix that constant gear change

 

I may have failed to mention, once it starts downhill it may go a half a mile before it shifts back into high gear. Do you think that's a tune issue as well? Thanks in advance.

 

Mine does the same. I think the truck downshifts to use engine braking rather than applying the brakes to maintain the set speed when going downhill.
Not sure how the tune would affect that but there’s a thread on the OTT on this forum and the tuners are really responsive and helpful to questions.

mine is stock so I don’t have that tune yet but I’m really considering it

 

Different engine, different tune to meet more restrictive emissions and fuel economy requirements.

It's possible the 2021-2023 FJs sold in Emirates are just as flaky, but we aren't likely to find out.

So is your complaint about the transmission shifting too much, or too little?

 

Apparently I am failing to communicate part of my problem. When a transmission has to downshift in order to maintain speed climbing hill, once it is broken over the top of the hill and starts back down it won't shift back into high gear, it's not trying to slow

 

They both are 4.0 V6 with same HP & TQ and getting same fuel economy.

 

The Toyota dealership told us that this is normal behavior, based on them test driving other vehicles on the lot. My wife said that's not a good way to determine what's correct. She asked the service manager if he beats up his wife and then asks his next-door neighbor if he does the same, and he does, don't make it right. The service manager agreed.

 

Normal. Manually drop it down to sloppy 4th and it will maintain.

My 2010 Tacoma did the same until I supercharged.

 

Fact of the matter is, your 4Runner is at least 500 lbs. heavier than the FJ. Same engine (1GR with dual-VVT), but add 500 lbs of weight and you're going to see more downshifts. Also, at 80mph you're driving a brick into the wind. As for the lack of upshift after cresting, mine does the same on radar cruise. Several other people have said the same thing. Who knows why it's tuned like that, but it is. The dealer is right, it's normal for however the tune was mapped at the factory. Maybe they tuned it to "hold" the downshift anticipating another climb. Or maybe the tune is to provide engine braking after cresting. Or maybe it's a bad factory tune applied to every TSS 4Runner. It is what it is.

You have a couple choices: 1. get an aftermarket tune or 2. don't drive 80 on the highway. I find a DRASTIC difference in fuel economy and shift behavior between about 74 and 80. Anything above 75 and you're just fighting wind resistance.

 

Good answer, thanks.

 

LOL, agree with your wife’s sentiment (and the delivery), but dealers are looking to say no to warranty even if something actually is wrong. At least they didn’t charge you an hour of diagnostic time to tell you.

Your 4runner is fairly new. It may need some time for the computer to “learn” whatever it learns. I’ve heard the complaint of it holding gears downhill in cruise, and mine sometimes seems to do it with the right combination of speed/grade/drag. I usually won’t suffer that bad behavior for long, and just disengage it when it doesn’t do things smoothly. But that’s because I’m used to “dumb” cruise, and have no expectations.

Actually, I have the opposite, which is an expectation that these things tend to get dumber the “smarter” they get. The radar cruise can also give you some nasty/scary surprises in some situations that you wouldn’t ever expect with normal CC.

 

Another excellent answer, thank you.

 

There is one incredibly easy way to get it to shift in cruise when it decides to hold a lower gear… simply tap the gas pedal about 1/4 of the way and let off and it will shift right away. Happens 100% of the time.

 

OP you are overthinking this. All the posts and calls to the dealer and beaten wife anecdotes still lead to "normal behavior". It is what it is.

 

Our trucks all do the exact same thing. It feels weird when it holds 4th gear for longer than expected after cresting. Just one of the 4runner quirks.

You'll also notice it's not always the same on the same hill. Sometimes it'll go back to 5th sooner, sometimes later. I suppose there are several factors involved; speed, wind, RPM's, weight, grade, etc. The throttle mapping is pretty complex.

The 4Runner shines as a jack of all trades. Great off road and pretty good at 75mph on the highway. But it has its quirks, no doubt.

There's a neat chart floating around here somewhere illustrating the throttle mapping. Somewhere in that chart you'll find out what conditions cause your truck to hold 4th after cresting a hill. And also why the next time you crest the hill, it'll go back to 5th a lot sooner.

 

Normal. My 2016 does this same thing. CC is worthless and only gripe with 4R.