4 cyl., auto., cruise

Hi from Kansas. I have a 20010 Tacoma 4 cyl., auto with cruise control. I find it frustrating when I go up a fairly steep grade at say 65 MPH and the transmission will drop down to low gear making the RPM go to 5000 to maintain the speed. Is this normal? I wish it would drop to third or second gear and let the speed drop if it must. I think this must be hard on the engine and the mileage. Can it be reprogrammed or should I just take it out of cruse when I think this is going to take place? Thanks - Glassfixer

 

Welcome to TW. It's normal for a transmission to down shift when the cruise is set to maintain speed. I doubt very much that your truck is going into low gear at 65 mph. It would probably blow up, if the computer would even let that happen. Best thing to do if it bothers you is to shut of the cruise and control the speed with your accelerator.

 

Yeah I run into the same issue. I just turn cruise off when I know it's going to kick down a gear and rev up a hill.

 

I just move the knob into 3 gear for the duration of the hill. It will hold the speed with no problem with it on .

 

I tried what BigMac suggested and so I haven't had the RPM go to 5000. Thanks for all of your input. - Glassfixer

 

Same issue (though I think mine only drops to 2nd), and I resolve it the same as BigMac. Trick for me is anticipating which inclines are steep/long enough to cause the overly-agressive kick-down and get it to 3rd before that happens - and then remember to move the selector back to D at the crest.

Tom

 

Cruise shouldn't be used on steep grades because it will cause the transmission to go back and forth between gears, hurting your gas mileage.

 

I only use cruise on flat interstate. It will kill your mpg on even the slightest grades, even if you have the V6.
Just my 2cents.

 

That's what I usually do. Next time, I'll leave the cruise on and bump the AT over to 3rd when starting the incline, just to see how that works. Wish me luck! (BOOOOOOOM!)

 

I know this is about those who have cruise, but some may not yet. Very good info. Cruise Control Install

 

Mine does the same thing. Stupid computer programming. What is odd, is I can cancel the cruise, keep the throttle in the same position, and it might slow down 1mph, and still stay in overdrive.

Reckon they can make a TSB on this?

Tim Glover

 

I've forgotten the last few times up the hill hopefully next time I'll remember to bump down to 3rd and see what happens.

It's really a predictable behavior for just about any cruise control system because it won't increase the throttle until the speed slows down and by then, well, we've slowed down and the motor needs to play catch-up. With a human controlling the throttle we can anticipate the hill and put a little more foot into it before the incline arrives. Cruise can't do that, not yet, but pretty soon I'm sure... probably an adaptive cruise from a Japanese or German manufacturer.

 

OK, the last time I went up the local big hill I left it in cruise and bumped down to 3rd. Sure enough, the cruise kicked in strong and kept it at 65mph steady. So that answers my (our?) question.