Towing with a Toyota Picnic

Nov 17, 2013
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What was the Toyota Picnic like to two with? We are between towcars and are thinking of using our second car as an itermediate, a 2.2 Diesel Picnic to tow our Abbey Adventura with an MTPLN of 1350kg - any thoughts, advice or memories?
 
Mar 14, 2005
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From the information I can find about the Toyota Picnic (97-01) 2.2 TD GLS 5d (SR) (7 Seat) I get the following specification

Unladen weight 1410Kg
Max Braked tow 1500.
BHP 86.

You tell us you have an Abbey Adventura with an MTPLN of 1350kg.

First of all the caravan is within the car manufactures towing limit so technically its legal. But dialling these figures into the towing ratio gives us
1350/1410 = 96%
This is towards the top of the Caravan Industries recommended towing ratio for experienced caravanners.

What does concern me is the vehicles meagre 86BHP, This is certainly a lot less than most 2.2 Diesel engines output, and I suspect it will struggle to make good progress with a car full of passengers and a laden caravan probably topping 3 tonnes combined weight. (28.6 BHP/Tonne)

Just based on the figures alone, I really think that with your given caravan, you need to look for a more powerful towcar
 
Aug 11, 2010
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sigh.. the toyota has 151 foot/pounds of torque, which is sufficient pull/power to tow at all legal speed limits, and would keep up with traffic if they are adhering to national speed limits,which i assume we all do...28.6bhp/tonne! is far better than my lorry has and its more than capable of holding its own..Alas those bhp/tonne figures, where invented and made to be used with non turbo petrol engines when torque was almost linear to bhp ie 85bhp 90ft/Ib of torque,and not whith forced fed diesel motors!!!!!!
ok by modern vehicles both the bhp and torque are not that good but 25 odd years ago they were good enough to by the citroen BX.. towcar of the year...............................OK slightly unfair but ...so is using that old system bhp/tonne when you have 50% more torque than what was assumed you'd have..
 
Nov 6, 2005
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The Caravan Club used to recommend, possibly still does, that 40 bhp/tonne of outfit weight is a good minimum - that includes diesels, both turbo and non-turbo, for which no concession is made.
Power-to-weight is reflected in acceleration rather that steady speeds and 28 bhp/tonne won't keep up with traffic long before NSLs are reached.
 
Aug 11, 2010
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RogerL said:
The Caravan Club used to recommend, possibly still does, that 40 bhp/tonne of outfit weight is a good minimum - that includes diesels, both turbo and non-turbo, for which no concession is made.
Power-to-weight is reflected in acceleration rather that steady speeds and 28 bhp/tonne won't keep up with traffic long before NSLs are reached.
thanks for that roger, they also recommend the 85% weight rule, both are unfounded and in the case of the 40bhp/tonne recommendations, pretty nieve to say the least given the known advantages of forced induction and its far greater torque,qualities against normal asparated engines......as for the not keeping up with traffic long before NSL are reached!!! 240 bhp divided by 8.5 tonnes is my unladen weight 28.4bhp/tonne......only the likes of bmw man flies by me off roundabout onto daulcarriageways and plenty of cars that are not towing are slower than me to NSL! reallt do dislike this bhp thing when it doesnt take into account torque!
 
Nov 6, 2005
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JonnyG said:
240 bhp divided by 8.5 tonnes is my unladen weight 28.4bhp/tonne......only the likes of bmw man flies by me off roundabout onto daulcarriageways and plenty of cars that are not towing are slower than me to NSL!
I'd be past you, even with the caravan on. You may be quicker to NSL than some solo drivers, but only because they aren't using full throttle, or anything like.
The thing with power is that you can calculate power-to-weight, usually using peak power, and the acceleration is directly proportional to the average power-to-weight - because the power is the same whichever gear you're in.
If you try calculating torque-to-weight you have to divide by the gear and final drive ratios so torque-to-weight at the wheels gets less-and-less as you go up the gearbox
 
Aug 11, 2010
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RogerL said:
JonnyG said:
240 bhp divided by 8.5 tonnes is my unladen weight 28.4bhp/tonne......only the likes of bmw man flies by me off roundabout onto daulcarriageways and plenty of cars that are not towing are slower than me to NSL!
I'd be past you, even with the caravan on. You may be quicker to NSL than some solo drivers, but only because they aren't using full throttle, or anything like.
The thing with power is that you can calculate power-to-weight, usually using peak power, and the acceleration is directly proportional to the average power-to-weight - because the power is the same whichever gear you're in.
If you try calculating torque-to-weight you have to divide by the gear and final drive ratios so torque-to-weight at the wheels gets less-and-less as you go up the gearbox
the fact you have much more torque in todays modern diesels than was anticipated using those silly old rules means you have more torque than those old rules anticipated everywhere..as for exceleration! torque is a player two similar cars ie bhp weight gearing if one has more torquethe one with more torque will excellerate quicker, from stand still or whilst in motion in any gear....
please lets not go kidding anyone deisels popularity here in the UK coincided with the adding of a forced induction and its inherent torque advantage ...
and roger its not about whether you'd be passed me,its about whether one would be holding up traffic and as many drive slower than even my lorry the answers is No you wouldnt be holding up traffic
... Ford galaxy 1.9 tdi were popular for towing never herd anyone complain that they werent good towcars,never herd anyone complain they were too slow,infact they were popular because they were decent...my outfit, galaxy plus burstner equaled 3,3 tonnes 115 bhp means far less than the quoted 40bhp/tonne....been here before sigh
 
Mar 14, 2005
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Now to be fair Jonny does have point, and I have also concluded that the CC recommendation of 40BHP/Ton (Old Units), rather like the 85% novice towing ratio advice fails to take into account modern developments in vehicle technology, and I also question whether it is the most appropriate comparator.

Whether quoting BHP/T is the best way of comparing outfits is open to debate, but it is at least a method which is accepted by most and it does give a general feel of likely towing ability.

I believe that these days a recommendation of 35BHP/Tonne(new units) for turbo diesels is probably sufficient, but dropping below that is I think loosing too much performance, hence my comment.
 
Aug 11, 2010
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roger are you mixing up engine torque with transmitted torque? if an engine develops 200ft/Ibs of torque at 2000rpm it does so in all gears,its one of the reason the power/torque of my mondeo mk3 2.2tdi is resticted in 1st and 2nd gear to stop the almost 300ft/Ibs from destroying the gearbox.. I'd like to see some sort of new measurement that took into account modern torque outputs as well as BHP,I mean what is adiquent pulling power these days?
 
Nov 6, 2005
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I have a turbo-diesel Santa Fe - 194bhp / 322lbft - laden my outfit is around 3.8 tonnes so a power-to-weight ratio of 51 bhp/tonne, above the CC recommendation but not by that much. If I was towing a heavy caravan, as many do, my power-to-weight would be down to 45 bhp/tonne.
If my power-to-weight ratio was further reduced to 28, I'd be a serious obstruction to other road users.
 
Aug 11, 2010
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so what youre saying is say an old decent tug like a mitsubishi shogun circa pre 2000 and having only 120 odd bhp weighting say 4 tonnes when towing is not a good outfit?! and would imped others!! thats grazy after all i am only allowed to drive at 40 mph in my 14 tonne lorry on an A road by law,so not sure what youre getting at here the speed limit for towing on an A road is 50mph 28bhp per tonne is more than adequite to do that speed. as im under that 28bhp figure [lorry] and by law i am not an obstruction and by law i am not impeding either, i'm at a loss as to what youre going on about. my ford galaxy could hold 50 mph on a straight and up modest hills which was the speed limit for towing on A roads as far as i'm concerned surely this is the only criteria that counts as to whether something is a capable tug? and not whether its slower by 3 seconds to 50mph than somebody else,afterall if you were to apply that rule then surely some would feel you impede them and obstruct them if they have far better bhp/tonne ratio's?and want to excelerate even quicker than you?
 
Nov 17, 2013
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Gents, thanks for your thoughts –sorry but I did not mean to
cause such a heated response!

Prof John, thanks for the numbers – we have done a fair bit
of towing and we are only looking at a few local journey’s but it gives me some
guidance on taking it steady! Using the Picnic is meant to only be a temp
measure until we decide what to replace our Galaxy with.

The Galaxy was a company car which made a lot of sense when
the kids were at home now they are gone we are going to abandon the company car
and buy something of our own but we can’t make our minds up!!! So in the meantime,
rather than park the van up, I thought we would convince the Picnic to tow it.

Bearing in mind that the first time we took a van out we had
a MK4 Cortina Estate that we had paid £100 for and which the temp gauge ran the
whole journey in the red – we should be pretty good in the Picnic!!

I suppose what I was hoping for was an ‘old caravaner’ who
had experiences of this car and could say if we were flogging a dead horse!!!
 
Dec 2, 2009
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Can I reply as someone who regularly tows with what some would consider would be a less than adequate power to weight ratio?

We have a 2013 Lunar Clubman SE - MTPLM of 1,495Kg. We tow with a Vauxhall Vivaro van - GVW 2,735Kg. Total max train weight of just over 4.2 Tonnes. The Vivaro 2.0CDTI diesel is rated at 115BHP giving a ratio of 27.19 BHP per Tonne. What the Vivaro does have is 290Nm or 215 ft lb of torque. This coupled with 6 speed gear box means that when accelerating I can easily keep the revs in the optimum power band & the turbo spinning.

I have no trouble keping up with traffic under acceleration. Typical scenarios such as pulling away from a junction or pulling off a slip road onto a motorway & accelerating up to speed do not cause dramas. On motorways & dual carriageways I can keep it in 6th gear from an indicated 52mph on the flat, anything less & I do have to drop down to 5th. When cruising at 60mph I can tackle all but the steepest of motorway hills. When driving on sigle carriageway roads, I can maintain 5th gear from about 40mph on the flat.

I'm firmly of the opinion that a solid engine with lots of torque coupled to a suitably configured drive train is what is important. I've considered having the engine remapped several times, but at a cost of over £400. & most of the remaps I have seen are for extra BHP without corresponding increases in torque values, I have decided that it's not worth it.

Cheers,
Jim
 
Oct 28, 2006
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The responces here are completely text book as nearly always on this forum.Many years ago we ran 38t tractors with 250 and 290hp non charged cooled and charged cooled engines engines fitted.That works out at 6hp and 7.5hp per tonne.We didnt have any problems keeping up with traffic.As far as im aware the NSL hasnt increased so whats the problem?What matters more is were the toyota makes its 150 odd lbsft of torque and the gearing.My car makes masses of hp and masses of torque,but because its so high geared(60mph at 1250rpm) it seems to be wasted.Use the gearbox and its a different matter.But i would think at worst it might drop off a bit on hills.I can remember the days when nobody mentioned hp,it all went on engine size.
 
Nov 6, 2005
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A couple of posts seem to think that HGV pace is "keeping up with the traffic" - on that basis a Mini 850 could probably tow a big twin axle !
 
Oct 28, 2006
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And isnt it?I cant remember the last time an hgv got in my way.So to me thats keeping up with traffic.Remember an outfit can only travel at 60mph legally.
 
Nov 6, 2005
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I regard the ability to keep up with traffic as being important on single carriageway roads.
Even vehicles/oufits with very low power-to-weight ratios and poor performance can reach their legal cruising speed eventually on dual carriageways - but that doesn't constitute "keeping up with traffic".
 
Mar 10, 2006
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The recommended torque for towing is 80 pound feet per ton.
If you have that then towing will be a relaxing affair.
 
Nov 6, 2005
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RAY said:
The recommended torque for towing is 80 pound feet per ton.
If you have that then towing will be a relaxing affair.
Who recommends it?
Mathematicians among you will realise that "pound feet per ton" is a pointless unit of measure - a ton is 2240 pounds so you have pounds on top and bottom of the calculation, which cancel each other out.
So 80 pound feet per ton = 80 pound feet per 2240 pounds = 80/2240 feet = 1/28 feet = about 11mm !!!!

My 2.2CRDi Santa Fe, with 194bhp 322ftlb, towing 1495kg is "only" 82 on your basis.
 
Mar 10, 2006
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80 pound feet per 1000kg. Metric ton.

I believe i've read it on the PC site, i've checked it against my tow, and find the figure near enough to be good advice.

Applying it to my last rig. van 1565kg plus car 1725kg, divided by 1000, and multiplied by 80 = 263 approx.
I towed ok with 266 pound feet.

Now towing with a 310 pound feet CX-5 its effortless. kerb of 1710kg approx.
 
Mar 10, 2006
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Found the link.
"Look at the power and torque (or twisting force) figures of the engine, too. Way back when, caravanners were often advised that 40bhp per tonne was needed when towing, but it’s torque that really counts. A modern equivalent of that old rule is that a car with 80lb.ft of torque for every tonne of car and caravan should give strong performance. Many will be able to tow happily with less, but drop to 60lb.ft per tonne and acceleration will be quite sluggish."

http://www.practicalcaravan.com/advice/how-choose-towcar

I've applied it using a metric ton, but it could be imperial?
At anyrate it works for me using a metric ton.
 
Nov 6, 2005
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There's only a very small difference between imperial ton and metric tonne (1 imperial ton =1.016 metric tonnes) and for many purposes, including this, can be used interchangeably.
 
Mar 10, 2006
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I forgot to mention that i also only used kerbweight with a driver, not the loaded car weight, but it is only a rough guide, like the 85% recommendation.
 
Mar 10, 2006
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RogerL said:
There's only a very small difference between imperial ton and metric tonne (1 imperial ton =1.016 metric tonnes) and for many purposes, including this, can be used interchangeably.

I've just googled tonne, which is apparently a metric ton. Just showing my ignorance.
 
Aug 11, 2010
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RogerL said:
I regard the ability to keep up with traffic as being important on single carriageway roads.
Even vehicles/oufits with very low power-to-weight ratios and poor performance can reach their legal cruising speed eventually on dual carriageways - but that doesn't constitute "keeping up with traffic".
i do worry Roger i mean when sorry if i excelerate hard in say my car upto legal speeds you wouldnt keep up with me whilst towing so maybe i could say you are not keeping up with traffic that being me..!but i suppose you'd eventually reach your legal speed!!...
or another way is to say if i was behind you in my car you would hold me up due to me maybe wanting to legally excellerate faster than you could towing your outfit! so there is no difference between a so called low powered car apparently holding up traffic in your words and you holding up traffic if i was stuck behind you.. all that is different is your perception that you excelerate fast enough to the legal speed, because you think you do and therefore you are not holding anybody up.....
 

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