I have a 2007 4runner sport 4.7 . I pull a 4000lb boat with it. I have noticed sometimes while going down a hill coasting the transmission downshifts on its own. I am not sure if I tapped the brake pedal before it downshifted. Can anyone help me on this.Will the transmission do this on its own or is it something I have to engage the transmission . I didn't manually downshift it did it own its own. I bought the 4runner last year and didn't get a owners manual with it. Any information will helpful.. P.S I love my 4runner and this my is my 6th Toyota and will not be my last. Thanks Buzz
downshift while coasting downhill.
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WillK
New member
My '06 does it too if I'm "in between gears" going down hill. I know some cars do it to stay in the powerband. I would assume that's what my Runner is doing.
If it really bothers you, try shifting to fourth manually,then back to fifth and it should go into fifth. I've done it a few times as it shifts that way.
If it really bothers you, try shifting to fourth manually,then back to fifth and it should go into fifth. I've done it a few times as it shifts that way.
NJshadow93
New member
It's just engine braking, completely normal.
I have a related, more general question about engine braking / down shifting.
I have a 2003 V6 automatic. I live in a hilly NE town. We have lots of in town roads where there's a stop sign at the bottom of a 1/2 mile long 30mph decline. I notice folks pumping / leaning on the brakes at least 1/2 the distance of the decline. I generally drop the transmission into 3rd gear coast all the way down the hill. Sometimes dropping it into 2nd near the bottom.
Is there any downside to down shifting and letting the engine do the braking? In the opposite situation, I imagine there's quite a bit heat build up and wear on the brakes pads....
All info is appreciated,
F
kakuno
New member
I feel the same way when going downhill and it shifts from fifth to fourth. almost seems like too much of a change in gear ratio. Makes me feel like a new driver when it does it. As I get to know the runner better, I've found that a light brake application during this shift has made it smoother.
Martinjmpr
New member
Pretty sure DAC only works in lo range 4wd and with the tranny in 1st/L.
Tooltime19
New member
It will not hurt to downshift if done properly. I downshift when im really running her hard on off road trails and long downhills. Just use your heads and try not to over rev the motor. If you are on a long downhill and find yourself riding the brakes too much then that is truly the time to be using a lower gear. Overheated brakes is a real bad thing, especially when you really need to stop.
TechWrench
Senior Member
:iagree:
Not saying you're wrong Casper421, but isn't this only true if you can't maintain 5th gear with the torque converter locked? If you can pull in 5th gear, and keep the torque converter locked, shouldn't that keep transmission temps lower (and prolong the life)?
Torque converter locked? What year did Toyota introduce that? I'm the recent owner of a 2003, I haven't found anything about this...
Greydog
Member
I like the downshift feature, though I agree that it's abrupt sometimes, mostly when I touch the brake pedal, the computer reacts more aggressively to slow the vehicle.
One aspect I like of this feature is during the winter, and when In 4Hi, the computers seem to use different mapping and manage the downshift points well, never had a wildly slipping episode.
I also discovered that when going downhill with no throttle, it will downshift and also apply some brake to manage speed, which has worked well in slick/icy situations. It seems to act somewhat like DAC with looser limits.
One aspect I like of this feature is during the winter, and when In 4Hi, the computers seem to use different mapping and manage the downshift points well, never had a wildly slipping episode.
I also discovered that when going downhill with no throttle, it will downshift and also apply some brake to manage speed, which has worked well in slick/icy situations. It seems to act somewhat like DAC with looser limits.
Martinjmpr
New member
I do a lot of towing with my T4R and I have a Scangauge II that allows me to see transmission temps.
What I have noticed is that the thing that will cause trans temps to rise is anything that causes the transmission to shift a lot. Based on that, I have adopted the following practices that seem to work very well for me:
* On relatively flat ground, once I am up to highway speed I put the transmission in D to allow me to use OD/5th. I also keep an eye on the temp.
* If I start to ascend a hill, I shift down to 4 before the transmission "kicks down" to 4th gear.
* If neccessary, I'll manually shift to 3 to climb a hill or accellerate.
* Going DOWN a steep hill I almost always shift it to 4 to allow for engine/gear braking and to save wear on the brakes.
* If I am in D and the temp starts to get close to 200, I immediately drop it into 4th and that usually makes the transmission temp drop as well.
Going up a steep hill while pulling the trailer it's normal for the trans temp to get as high as 220f. It always cools down rapidly as soon as I get to the top of the hill and start descending.
Incidentally, I've never had the trans temp light on the dash come on. I don't know what temperature activates that light, I think the highest trans temp I've ever had was maybe 230.
KidVermicious
New member
Brakes are cheaper and easier to replace than torque converters. I'll use compression to brake on long descents where brake fade is a concern, but not really around town, not with an automatic anyway.
5th gear will "lock" the torque converter automatically. Have you noticed while cruising in 5th, if you accelerate a little, your RPMs will jump a few hundred? This is the torque converter unlocking. If you relax off the pedal a little the RPMs should drop back down as the torque converter locks.
In a 2003 this might be different because I believe you have a 4 speed. In my 2007's this is how it works.