Using Cruise Control on Hils

[Snagglefoot]

Since Bitgoers tend to take better care of their cars than most (normal) people, how many here prefer to take the car out of crise control on large hills where otherwise the car would get after it and drop a few gears to rev higher , on mine, sometimes to 4,000 RPM. When using the gas pedal I can accelerate up the hill just fine without dropping the gears. In my case I was doing 70 mph and it dropped a few gears and suddenly went from 2,100 to 4,000 rpm just to climb up the hill.

 

[PimTac]

On a typical freeway hill with light traffic I use the cruise until I sense the transmission is hunting gears then I go manual. Most mountain passes keep me manual but the long straight hills will have me in cruise control. On regular highways I stick to manual.

 

[JHZR2]

I find that driving is much smoother and more efficient off cruise.

No need necessarily to keep full speed (conditions dependent), or necessarily such a severe downshift.

 

[FordBroncoVWJeta]

Originally Posted By: Snagglefoot
Since Bitgoers tend to take better care of their cars than most (normal) people, how many here prefer to take the car out of crise control on large hills where otherwise the car would get after it and drop a gear to rev higher , on mine, sometimes to 4,000 RPM. When using the gas pedal I can accelerate up the hill just fine without dropping the gear.
This is I hate automatics. This is why I try to purchase manuals.

 

[SZR48207]

Cruise only on flat interstates now. On a previous vehicle, I used cruise too much on hilly trips and I think the OD band burned up as a result.

 

[eyeofthetiger]

My cruise control car has a manual transmission. I take it out of cruise and downshift for steep hills. But for 99.9% of interstate highways, the only reason I have to take it out of cruise is the dang traffic.

 

[Snagglefoot]

Don’t know why the makers want the tranny to slam down and rev like crazy. Don’t want to lug it but there has to be something in between. Are there trans kits to calm it down?

 

[compratio10_5]

The replies here are right on. The most efficient way to drive for better mileage is to use constant throttle but since this results in going up hill slowly and down hill fast it is not safe and other drivers will hate you. Some newer vehicles are getting adaptive cruise control that will modify the speed setting depending upon the load and traffic but for the rest of us, shut off the cruise control in the mountains, on slick roads and in the heavy traffic.

 

[eyeofthetiger]

Originally Posted By: Snagglefoot
Don’t know why the makers want the tranny to slam down and rev like crazy. Don’t want to lug it but there has to be something in between. Are there trans kits to calm it down?


It's the programming, and inability of the cruise to an anticipate the hill. By the time it realizes it's on a hill, it has already lost several MPH. So it has to accelerate hard to get back up to speed while climbing. I might compensate for that by giving it some gas right at the bottom of the hill so it never loses that speed.

 

[SZR48207]

Originally Posted By: Snagglefoot
Don’t know why the makers want the tranny to slam down and rev like crazy. Don’t want to lug it but there has to be something in between. Are there trans kits to calm it down?


The PCM can't analyze the road ahead. Cruise control just tries to keep the speed at the set point.

If the terrain is hilly enough that it keeps dropping it a gear to catch up, you're better off modulating speed with your right foot.

 

[Linctex]

Originally Posted By: Snagglefoot
When using the gas pedal I can accelerate up the hill just fine without dropping the gears. In my case I was doing 70 mph and it dropped a few gears and suddenly went from 2,100 to 4,000 rpm just to climb up the hill.


I love my 2008 F150, but I often feel the "cruise control software" was written by the biggest dunce in the industry.

I can easily climb many hills in this area (this is Texas "Hill country")
and it never drops out of OD/TQ lockup if I just feather the gas and allow it to drop 5 mph.

Letting the computer set the speed and ridiculous down-shifting on mild hills with cruise on is EXTREMELY annoying to me.

 

[double vanos]

This is why I bought my ‘11 FX4 with Ecoboost engine and 3:73 gears. I takes one heck of a grade to make it even consider downshifting. I can gas up in Kerrville, Texas and drive to Fort Stockton 250 hilly miles away and it only shifts up to 6th once. Not one single downshift through the hill country and beyond. Torque rules.

Ecoboost engine + 3:73 gears = no downshifts.

 

[Snagglefoot]

Originally Posted By: Reddy45
Originally Posted By: Snagglefoot
Don’t know why the makers want the tranny to slam down and rev like crazy. Don’t want to lug it but there has to be something in between. Are there trans kits to calm it down?


The PCM can't analyze the road ahead. Cruise control just tries to keep the speed at the set point.

If the terrain is hilly enough that it keeps dropping it a gear to catch up, you're better off modulating speed with your right foot.


I now recall a trucker on this site told us his cruise control on his new Big Rig communicates with the truck’s GPS and will accelerate prior to a hill if things are clear ahead,

 

[Omahaug]

Quote:
Since Bitgoers tend to take better care of their cars than most (normal) people, how many here prefer to take the car out of crise control on large hills where otherwise the car would get after it and drop a few gears to rev higher , on mine, sometimes to 4,000 RPM. When using the gas pedal I can accelerate up the hill just fine without dropping the gears. In my case I was doing 70 mph and it dropped a few gears and suddenly went from 2,100 to 4,000 rpm just to climb up the hill.

I know exactly what you're talking about and I hate it too. The first time it happened to me, yeesh, never let it handle hills again, no thanks. I don't like the feeling.

AFAIK this is intentional and affects some cars when cruise control isn't used at all. For example on most Honda cars with AT's, if you're going down hill and you touch the brakes in a specific way, the AT drops gears shooting the RPM's up. Honda calls it "Grade Logic Control" where on hills it will try to detect them and either drop to lower gears, or maintain a lower gear entirely and never upshift, to make it easier to climb hills and also when descending hills to enhance engine braking.

On my last car, there was a hill on the commute where this would kick in consistently.

 

[MNgopher]

I always love the complaints when the cruise control is doing exactly what it is intended to do - maintain a set speed, everything else be.. well you get the idea.

Yes, you can often do better than the cruise because you have the ability to react to stimuli that the cruise does not - namely you can see what is coming. The cruise only knows what has happened and what it needs to do to catch up or let off.

And the complaints that it downshifts even on smaller hills - high overdrive gearing will do that. Particularly with NA engines that tend to need to rev a bit produce their power... say a 5.0 V8 in the F150... Not a criticism of that package, just the reality of how it needs to be operated.

And I'll agree with a poster above - put an Ecoboost in the same truck, and you see a lot of those downshifts go away. Then we can debate running high boost at lower rpms, but that's another story...

 

[ammolab]

Plenty of major hills in the N Mexico Mountians but no major traffic...so I run cruise most of the time. With a manual gearbox and 415 ft pounds of torque in the Chevy I roll up those hills at highway speed in cruise with little effort.

 

[CharBaby]

I often take the engine out of CC when climbing steeper hills as I believe that I can ease the throttle more gingerly in order to keep the revs lower. Otherwise, the system often revs higher than need be to climb the grade.

 

[RooflessVW]

I use cruise.

4k rpm? The horror! Definitely going to pop that engine. Maybe you need a more powerful car.

 

[demarpaint]

Originally Posted By: double vanos
This is why I bought my ‘11 FX4 with Ecoboost engine and 3:73 gears. I takes one heck of a grade to make it even consider downshifting. I can gas up in Kerrville, Texas and drive to Fort Stockton 250 hilly miles away and it only shifts up to 6th once. Not one single downshift through the hill country and beyond. Torque rules.

Ecoboost engine + 3:73 gears = no downshifts.


I agree, if the engine is making enough power and is geared right there will be very little downshifting in most instances. As you say torque rules.

 

[Quattro Pete]

Originally Posted By: Snagglefoot
Since Bitgoers tend to take better care of their cars than most (normal) people, how many here prefer to take the car out of crise control on large hills where otherwise the car would get after it and drop a few gears to rev higher , on mine, sometimes to 4,000 RPM.

When cruise control is on, my car will not drop any gears because it's a manual, so I have no problem keeping the CC on.

However, in a hilly terrain, you can achieve better fuel economy if you disable CC and just allow the car to slow down a bit going up hill, knowing that you will will speed back up again when going down hill.