[LynyrdSkynyrd]

My 2017 gas promaster has decided to begin downshifting into 4 th gear when going down hills. Like a diesel brake using tranny. I am not in tow haul. Or manual. Anybody experience this. Rpm high. This can't be normal operation. And there is no real way to get it to shift out. It just shifts back on its own also.

 

[LynyrdSkynyrd]

I forgot to mention. It this is happening at highway speeds

 

[Peter Masson]

I forgot to mention. It this is happening at highway speeds

I understand this is normal operation. I live in Utah and like having it in the mountains. You just have to tap the gas and it will shift back.


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[LynyrdSkynyrd]

I tried that today, but it takes awhile to kick out of the gear, I am a little concerned at the high revs, but this tranny is different than any I have had before.. I am just hoping I can get lots of miles out of it, I will be taking it in for this conceren, just to see what they say... I will post the results.

 

[VanShopping]

It's the one thing I find annoying about the transmission, and like you I find it takes a while to kick back out of the lower gear. Giving it gas does help. I'm interested in what you find out from the dealer.

 

[watercamper]

I agree with Peter. I live in the mountains and actually like the feature. A quick tap on the gas and it shifts for me.

 

[canuck4everr]

After 4000 k i have had this happen 3 times , highway speed start decline , take foot off gas , then revs go to 4000+ rpm.
Tried manual shifting to a lower gear but will not work.
Will try the tap on gas method.
Interested if you get info about this .

 

[RDinNHandAZ]

I’m a downhill coaster not a revver! I hate the downshifts. None of my other older vehicles do this and I was led to believe all new ones do. NOT. I just talked to a friend with a new Highlander and he says his doesn’t. If there was one thing I would change on my van it is the aggravating downshifts often on slight descents. Thankfully I have a diesel so a flip of the AMT shifter to Manual lets me shift right back up and unless I get on the brakes it stays up. My dealership has steadfastly refused changing any programming including the TPMS pressure, seatbelt beeps, etc. as they say it is not allowed. I want a programmer! Anyone into hacking the computer on this thing or sending me the FCA access codes? Oddly my manual doesn’t give me the process to change it.

 

[mwsheets]

Are you using cruise control? The down shift happens on almost all hills if you are using cruise. Without cruise control it still happens consistently on steeper hills, enough that it annoyed me at first but quickly got used to it, but with cruise on it was driving me batty. I grew up with a manual transmission and would prefer to take it out of gear and let it roll, but if you look at your instant gas mileage when it bumps up the rpms you aren't burning through gas. It's mostly just engine braking.

It really didn't like it when I tried to defeat it by popping her into neutral on a long steep hill. Worked for awhile, till I put it back into drive, **** of a lurch and engine didn't have a clue what to do.

 

[keeponvaning]

After 82k miles I don't even notice it anymore! In fact, it never bothered me before either.

 

[RDinNHandAZ]

With or without cruise on the diesel. Generally I am not in cruise. On secondary roads it will go down to 4th after pulling up a steep grade in 5th. You get to the top and nose down and before it gets a chance to upshift to 6th it will sense the slight downhill and go down to 4th. It does no harm and if the van doesn’t speed up it will go up to 5th sometimes, but never to 6th where it should be. It’s my irritation with the built-in programming not a defect per se. I just wish it could be turned off or the hill sensor could be disabled or tilted to have it activate the downshift when the hill was truly steep enough to warrant a downshift. Overriding the ATM with the lever in M is fine and I expect many of us use it a lot but if not for this one quirk I would use M about once a month or so not daily.
The real issue here is do we let the machine train us to its desires like it has KOV or do we use M to impose our will on the machine?

 

[LynyrdSkynyrd]

I have to agree with all of you that find it irritating, I think the real problem here is that this has to be hard on the trans, I am loaded wtih all my tools and lots of parts and wire, electrical contractor van, so I am carrying some weight. I will be getting it in soon, I will post all the info when I find out.If it is normal, then so be it, I do enjoy the van, easy to steer, turning radius is insane, its fun.

 

[LynyrdSkynyrd]

Oh and today it was doing it again, and I tried tap the gas, tap the brake, tap the steering wheel, none of that works, it shifts out when it feels like it, no I am not in cruise control, or tow haul, just to let you all know.
As for it being programed to do this, maybe, you are thinking like diesel braking in the silverado when it is in tow haul?, even in the silverado you can tap the fuel and it will shift, and you can tap the brake and it will downshift, but that is one tough trans, Alison it can take this, but this little trans? Not so sure.
Thanks for all of the feed back, this is a great site, and I love all of the detail everyone puts in there post.

 

[LynyrdSkynyrd]

So the truck is in the dealership, they are suspecting shift solenoid and replacement. Keep you all posted, this also has to do with my thread about the jerky backup....

 

[LynyrdSkynyrd]

Well, no help at davis dodge Hanlees, they dont have a transmission guy so they cant reproduce the problem, so they checked fluid and codes, no codes. So supposedly its good to go...
We will see! If its normal so be it.

 

[grnd0]

It's the way the programming and tranny work. Mine does the same thing. I travel to Colorado and get on some serious downhill grades. My biggest gripe is the crazy downshifting can't be stopped by using the manual mode. Don't like it at all.

 

[Swoop]

I live in the mountains and I have no objection to the automatic downshift. Engine braking seems better than overheated brakes. If I am on a steep grade, I let it downshift. If I am on a less steep grade, where it might downshift, but I don't need the braking, then I keep my foot very lightly on the gas pedal. That usually prevents the downshift and is essentially the same as coasting. The instant mpg bounces around in the 70-99.9 range.

Light pressure on the gas pedal tells the computer that you don't want to slow down. Taking your foot OFF of the pedal tells the computer that you don't want to go faster. If the hill causes you to increase speed, the computer responds by downshifting.

Several people have suggested tapping the gas. If you do that without maintaining very light pressure on the gas pedal, it may return to 6th gear, but then downshift again soon. If you do this repeatedly, then you may, in fact, be causing unnecessary wear on your transmission. (Likewise with shifting in and out of Neutral.) If keeping very light pressure on the gas pedal allows you to go too fast, then you probably NEED the downshift.

 

[MtBiker]

I like the way the transmission works downhill! It did seem odd and very different than anything I have driven before but I have embraced the fact that I do not have to ride the brakes while going downhill. The motor will wind up a bit and downshift to keep your speed from increasing but it works well.
Let it do the job it was programmed to do, let it just happen and after you get used to it you will likely come to miss it when in other vehicles'
We have about a 5 mile run downhill thru the hills and drop about 1400 feet. Speed limit is 50mph and if you just coast with out using the brakes you will hit 65+. I now just roll out onto the road and lift off the pedal at just over 50mph and it mostly stays right close whether empty or loaded up.

 

[Wankel7]

I don't find the feature annoying. What I find annoying is that I can't control the feature.

That part isn't cool.

I wonder how the computer senses the downshift is required?

Acceleration of the vehicle yet 0 percent on the throttle position sensor?

 

[Old Country Woodworks]

I like the feature, saves riding the brake when necessary.