Cruise Control - High RPMs on hills

The extra weight of the 3rd Gen most likely accounts for that.

 

Sure but comparing RPMs at which max horsepower is made is even more meaningless. 4.0L makes 236 hp at 5200 RPM, while 3.5 makes 278 hp at 6000 RPM. The thing is, 3.5 still makes more than 236 hp at 5200 RPM.

Your example for F1 engines doesn’t apply here because unlike a F1 car engine, neither trucks engine rev to 15k rpm, and both engines have more or less the upper rev limit.

 

I thought this would be locked by now.
Both are good engines, both are good trucks. Some people expect a truck to do certain things, while other people expect it to do certain things for them and their demands. Lawn guy towing the machinery every work day is looking for something different than the grocery getting office family crew.

 

My Tacoma is perfect for me. I gave up the 2011 Ram Hemi because I didn’t need the power any longer. I love it when people buy trucks with small engines and then complain the truck lacks power and shifts too much...duh.

 

It's not normal, but taco owners will insist it is.

 

Update: I used ECT with the cruise today and it was perfect. Above 70 and closer to 75, the rpms did go above 3k, barely and it was only on the large hills.

I actually prefer ect on all the time and may resort to using it all the time.

 

I also forgot to mention one other thing now that I'm thinking about it. You said you have 1k miles on the truck. That's the break in period. Often times you'll also notice worse MPG than rated because the engine has to work harder while being broken in. This possibly explains your shifting issues too (at least partly). They recommend you don't use cruise control during break in generally just to avoid constant RPMs, but obviously that's less of an issue when you're on hilly terrain.

 

They also say don't use cruise control on hilly terrain but here we are.

 

I actually have not ever heard that one.

 

It's in your manual

 

Not quite so much.

Just did a search of the manual and this was all I found.

It talks about STEEP hills, not regular hilly terrain. Each one of these pertains to losing traction (with exception of heavy traffic) due to the computer trying to maintain a certain speed. Each of these should be common sense as well. It also seems to be referencing going downhill more than anything.

 

I've been taught since I was a kid to not use cruise control if there's hilly terrain, traffic, or bad weather. And it looks like the manual agrees. Of course the term steep is pretty subjective...

 

define hilly terrain.. i mean there are no perfectly flat roads.. how much of an incline are we talking here to be considered "hilly"? my tacoma would do what they are talking about on roads with slight inclines.. nothing that i'd consider "hilly". like i keep saying the truck seems under geared to me. on the flip side my GMC doesn't do it and is easy to keep a steady speed/rpm but it is a V8 and set up totally different. .

 

Traffic and bad weather should be common sense, but "traffic" can be suggestive too. And yes, steep is suggestive. In this case it is talking about the possibility of the truck exceeding the set speed which is more of an issue on long, steep descents which you would likely find coming out of a mountain pass. In that case you should probably be grade shifting (or just riding the brakes and ruining them)

 

MT ftw

 

Yes, my 2017 TRDOR behaves similarly. I've discovered that the hysteresis of the cruise control system is very small. In other words, it doesn't allow the speed to decrease or increase more than about 1-2 mph from the set speed before it responds aggressively to get the truck back to the set speed as rapidly as possible. Because I can manually let speed decrease slightly more or increase slightly more from a desired speed when I'm the one modulating the throttle, I can keep the transmission from downshifting more often under the same conditions where the cruise control would immediately downshift.

I have also noticed that the cruise will often keep the transmission in a lower gear at steady state (say, 4th gear for a given throttle position) on flat ground despite the fact that I can depress the gas pedal to maintain that same speed, disengage the cruise, and the transmission will immediately upshift to 5th gear. Is this "normal"? I don't know. I have no other data points for comparison. It certainly is annoying. I describe the shift map vs. throttle position as "coarse" and "unrefined" on my truck.

 

Or the transmission could be tuned to make manual operation unnecessary.

 

DZ Custom Innovations makes a shift module that is about a 10 minute install and controls the shifting automatically when you put it in the "S" mode...

 

it's pretty normal behavior. i would rather it keep the revs at 4k on steep hills then lug the engine and constantly downshift...