Jump to content

Cruise Control


Fenrir
 Share

Recommended Posts

This may have been covered but please excuse me I'm new and can't find any previous discussion.

 

My last three tow cars have been automatics with cruise control. The question below is relative of all three of them.

 

My question is, have any of you found that when towing with the cruise control set you get less MPG than if you do a similar journey with it switched off.

I ask because my regular trip to the west coast of Scotland can differ upward in cost by some £20 if I use the cruise control.

 

Any thoughts?

Link to comment
Share on other sites

  • Replies 60
  • Created
  • Last Reply

Top Posters In This Topic

Hi Fenrir. Your question/query is not new but like a great many questions that are related to driving,whether solo or towing they can be and often are very subjective.

My own experience is that I have towed with Cruise Control enabled cars for many years and I do believe that there is a good case for questioning the likelihood of increased fuel consumption.

My own thoughts are that it is a very likely event with petrol power rather than with diesel power.

The newer multi ratio automatic gearboxes I believe are more likely to go down a few notches than stay in a higher ratio and pull the load.

Since I have gone Geartronic and also diesel I think that the returns are better but no by a vast margin.

Life in general can be a journey of chance with some winners and sadly some losers. Your outfit can never be left to chance. A short-while carrying out essential checks can ensure a long-time of happy & safe caravanning for all concerned.
Ignorance can often be bliss but is certainly not an excuse and when continually disregarded they can be totally disastrous for oneself and the innocent parties.

Link to comment
Share on other sites

Solo or towing, cruise will give better fuel consumption at steady cruising speeds, ie motorway but worse fuel consumption on hilly, twisty or narrow roads. Cruise also gives worse consumption in windy weather, it just bats on at the same speed regardless of power requirement.

2015 VW Touareg 3. 0 V6 TDI + 2013 Lunar Clubman ES

Link to comment
Share on other sites

Not only when towing, but also solo. Cruise control is brilliant if the road is fairly flat, but it's hills that are the problem. Where you can anticipate, cruise can't; it just reacts. Therefore you get the situation where you'll start climbing a hill and as the speed drops off a little, you'll either 1) have increased speed a little beforehand, or 2) allow the speed to drop off a bit. Cruise control will just try to keep the same speed, which in some cases means full throttle (and a change down a gear or two etc).

Edited by nigel207

1958 Morris Minor towing 2012 Hobby Landhaus

Link to comment
Share on other sites

Solo or towing, cruise will give better fuel consumption at steady cruising speeds, ie motorway but worse fuel consumption on hilly, twisty or narrow roads. Cruise also gives worse consumption in windy weather, it just bats on at the same speed regardless of power requirement.

:goodpost:

An eye for an eye only ends up making the whole world blind.

Mahatma Gandhi

Link to comment
Share on other sites

My disco 2 auto has two settings . . Normal & 'Sport' . . I can't prove it, but I think it performs better MPGwise in sport . . it changes down earlier, and up later than normal, and I think this keeps it in a better envelope.

 

JMO

Roughing it . . but in comfort . .

Link to comment
Share on other sites

We tow an auto with cruise control at every available opportunity. Havent noticed any difference in fuel consumption but as this tends to be only on motorways, it will be better mpg anyway than twisty non motorway roads.

 

I would also question the issue when climbing hills using cruise control.

 

 

My purpose for using cruise control is to allow regular movement of an ailing hip while on long european journeys. Its so much more restful to 'just steer'.

 

I am really not concerned about the cruise control trying to maintain speed in wind and on hills. I want to get where I am going in the alloted time and its been my observation that while the onboard computer display may drop to 11mpg for a short hill. ...it goes 90mpg for a much longer descent on the other side! Obviously on long alpine hauls I drop off cruise control, and accept loss of speed. But for 90% of motorway use I use cc.

Link to comment
Share on other sites

My question is, have any of you found that when towing with the cruise control set you get less MPG than if you do a similar journey with it switched off.

If you speed is the same then I cannot see why your fuel consumption should change if you use cruise control. Once you start talking about building up speed before a hill or other changes to your constant speed then you are not comparing like with like.

Link to comment
Share on other sites

If you speed is the same then I cannot see why your fuel consumption should change if you use cruise control. Once you start talking about building up speed before a hill or other changes to your constant speed then you are not comparing like with like.

 

Hi DACS. The simple truth of the matter is that whilst the speed is maintained,that is what Cruise Control is all about,the revs will increase on an incline as the gearbox changes down (Automatic/Geartronic) and it is REVS THAT USE FUEL.

Life in general can be a journey of chance with some winners and sadly some losers. Your outfit can never be left to chance. A short-while carrying out essential checks can ensure a long-time of happy & safe caravanning for all concerned.
Ignorance can often be bliss but is certainly not an excuse and when continually disregarded they can be totally disastrous for oneself and the innocent parties.

Link to comment
Share on other sites

For the same conditions the cruise control will save fuel BUT when driving manually we don't control the speed as well. Try it, reset the average speed display and then manually drive at a set speed as you normally would for say 10 minutes. Check your average speed, now set the cruise control to the same speed that you averaged and you will find you have used less fuel.

 

J

Link to comment
Share on other sites

I find cruise when towing always uses more fuel.

 

Solo, empty motorway, early hours I get better results from Cruise and it keeps the speed down as speed tends to creep up with myself driving on clear M Ways.

 

Most newer BMW's have brake function on cruise which is good when you are in roadworks or average speed cam areas but not good for economy, it will brake down the hill then power you up the other side wasting fuel.

 

Cheers

Lee

Yeti 2.0TDi EU6 150 DSG 4X4 L&K, Octavia TSi Manual, Fabia TSi DSG, Swift Challenger.

Link to comment
Share on other sites

Not only when towing, but also solo. Cruise control is brilliant if the road is fairly flat, but it's hills that are the problem. Where you can anticipate, cruise can't; it just reacts. Therefore you get the situation where you'll start climbing a hill and as the speed drops off a little, you'll either 1) have increased speed a little beforehand, or 2) allow the speed to drop off a bit. Cruise control will just try to keep the same speed, which in some cases means full throttle (and a change down a gear or two etc).

 

Not sure what the mpg difference is between arbitarily ' increasing speed a little beforehand ' and CC doing it when it's required?

 

Have never seen the point of allowing road speed to drop when going up hills. Just messes with your progress and annoys other road users you just overtook. Nothing more annoying on single carriageways than someone in front of you chopping and changing speed, unecessarily.

 

I suppose if we really wanted to save fuel on hills . ..we could get out and push.

Edited by ericfield
Link to comment
Share on other sites

Not sure what the mpg difference is between arbitarily ' increasing speed a little beforehand ' and CC doing it when it's required?

 

Have never seen the point of allowing road speed to drop when going up hills. Just messes with your progress and annoys other road users you just overtook. Nothing more annoying on single carriageways than someone in front of you chopping and changing speed, unecessarily.

 

I suppose if we really wanted to save fuel on hills . ..we could get out and push.

 

I totally agree, and always maintain a constant speed wherever possible. I was merely using that as an example of how cruise control can be inefficient, as it reacts to a situation rather than doing as we can, and anticipate. Plus, it's more likely that you would change down a gear or two much earlier to maintain that speed which is more efficient than doing as the cruise control does and waits to the last moment before "flooring" it, often labouring for a moment before kicking down a cog or two.

 

As you say, there's nothing more annoying than someone chopping and changing speed, especially when they've got a gutless tow car which is hopeless on hills!

Edited by nigel207

1958 Morris Minor towing 2012 Hobby Landhaus

Link to comment
Share on other sites

Thanks for the comments, all interesting stuff. I do switch the cruise off on "back roads" shall I say. The majority of it's use is on duel's and motorway. I use the A66 on the trip and it's that road that makes the difference I'm sure. Cruise control becomes very busy changing up and down at the drop of a hat where as in auto the gear box is a lot less active more gentle if you wish. It's a hilly and most of the time weather effected road but I love the scenery.

Just for fun I'm going to set the trip and computer on the next trip up when I get to Scotch Corner and get a figure.

Link to comment
Share on other sites

As you say, that's probably not the best route to use cruise control for towing as it's up hill and down dale (please excuse the pun!).

1958 Morris Minor towing 2012 Hobby Landhaus

Link to comment
Share on other sites

As you say, there's nothing more annoying than someone chopping and changing speed, especially when they've got a gutless tow car which is hopeless on hills!

 

 

Not just other towers. I seem to attract the solo morons who HAVE to overtake the caravan thats doing 58mph on a motorway. ..only to drop to 56mph in front of me. Why people can't keep a constant speed. ...overtake quicker. ..then drop back to that SAME constant speed.

 

Oh hang on. ..maybe they don't use cruise control. LOL

Link to comment
Share on other sites

Not just other towers. I seem to attract the solo morons who HAVE to overtake the caravan thats doing 58mph on a motorway. ..only to drop to 56mph in front of me. Why people can't keep a constant speed. ...overtake quicker. ..then drop back to that SAME constant speed.

 

Oh hang on. ..maybe they don't use cruise control. LOL

 

Cruise control does highlight how poor some folk are as you say. The criticism can be directed at all groups of road user.

 

Merry Christmas! :lol:

1958 Morris Minor towing 2012 Hobby Landhaus

Link to comment
Share on other sites

Well I'm one of those morons.

 

I find motorway driving mind bogglingly boring, and have no intention of looking at the back end of a caravan, or any other SUV for that matter, van etc.

 

Usually I find CC unusable because of traffic density, even on long stretches of road works at 50 mph limits, I can set the limit to the sat nav and still have someone creep past taking for ever to pass, or the plonker that wants to drive on your back end yards away.

 

So my motorway driving can vary from 50 mph up to 100 mph solo, I often overtake cars which later overtake me, its actually the only way I can drive on the motorway and keep awake

Link to comment
Share on other sites

Guest Benzowner

As Nigel has explained CC will use more fuel, its a convenience that you have to pay for.

Totally incorrect!

Cruise control is as it says, maintaining a set speed, which it will do so at the minimum level of throttle required, unlike our clunky right feet :D However, if cruise control is left on and you begin to travel up a steep hill, it will change down in an automatic, and use more fuel. If we drive up that same hill using our right foot, we will use more fuel than cruise, but we tend not to, we slow down on hill ascents. Many time I have been driving using the right foot, turned cruise control on and the revs have immediately dropped, but the speed has been mainained

Link to comment
Share on other sites

Totally incorrect!

Cruise control is as it says, maintaining a set speed, which it will do so at the minimum level of throttle required, unlike our clunky right feet :D However, if cruise control is left on and you begin to travel up a steep hill, it will change down in an automatic, and use more fuel. If we drive up that same hill using our right foot, we will use more fuel than cruise, but we tend not to, we slow down on hill ascents. Many time I have been driving using the right foot, turned cruise control on and the revs have immediately dropped, but the speed has been mainained

 

I think you are both right! If mainly motorway, CC wins usually. Up hills and CC's inability to gain speed downhill to benefit the next rise make it a different matter.

Overall though CC could use less or more fuel depending on driver's habits and terrain.

Sam :beardy:

Link to comment
Share on other sites

Totally incorrect!

Cruise control is as it says, maintaining a set speed, which it will do so at the minimum level of throttle required, unlike our clunky right feet :D However, if cruise control is left on and you begin to travel up a steep hill, it will change down in an automatic, and use more fuel. If we drive up that same hill using our right foot, we will use more fuel than cruise, but we tend not to, we slow down on hill ascents. Many time I have been driving using the right foot, turned cruise control on and the revs have immediately dropped, but the speed has been mainained

Why should the revs immediately drop?

The revs will always be the same for a given speed in a given gear, if you are accelerating?

Link to comment
Share on other sites

A lot also depends on how much control one has over their right foot! Someone with a heavy right foot will undoubtedly use more fuel than one with a light right foot. Cruise control will probably be somewhere in the middle.

1958 Morris Minor towing 2012 Hobby Landhaus

Link to comment
Share on other sites

I think you are both right! If mainly motorway, CC wins usually. Up hills and CC's inability to gain speed downhill to benefit the next rise make it a different matter.

Overall though CC could use less or more fuel depending on driver's habits and terrain.

As you say, CC will not allow you to gain speed on the downhill . ..but that's a good thing.

 

I travel at the legal limit on the flat and up hills. ..I don't want to go over the limit free wheeling (potentially dangerously) down the other side. The mpg invariably goes to 99mpg on the computer while descending even with CC active. ...that's not too bad. LOL

Link to comment
Share on other sites

As you say, CC will not allow you to gain speed on the downhill . ..but that's a good thing.

 

 

It does on most cars - if the hill is steep enough it'll exceed the set speed - most CC's just control the throtle.

 

There are one or two CC's that will apply brakes but very much the minority.

2015 VW Touareg 3. 0 V6 TDI + 2013 Lunar Clubman ES

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share


×
×
  • Create New...