Big Tank Slapper

[Merc808]

I travelled down to London from Beverley last Saturday, nothing to report quite incident and trouble free. I usually park at Cockfosters Tube Station and travel in. I just happened to chose the wrong weekend and had to catch a courtesy bus laid on to take us to Wood Green Tube station to continue the rest of my journey to Elephant & Castle.

Again apart from the delay of 40mins on the bus all trouble free. After picking up my daughter we did the return journey and again took the bus to Cockfosters. It was now 20.20 hrs and raining. Not a problem. We made good time and proceeded up the M1 as planned.

Not in a hurry and with the prevailing weather conditions of rain and drizzle, set the cruise for 65 mph. Tootling along in the inside lane I noticed the car moving slightly on the “Tarmac Tramlines” left by our HGV friends on our inadequately surfaced roads. I hadn’t noticed how bad these tramlines had got on the M1 until I was getting near to the M6 turn off. Now I remember myself commenting on thread not so long ago “ Pick a lane, any lane” about how car drivers sit in the middle lane and not returning to the near side. I found my self sitting in the middle lane as the tramlines were collecting water and moving the car quite considerably.

As previously mentioned I was approaching the M6 turn off, when following a caravan I saw one of the worst “ tank slappers” I have ever seen a caravan do. It got to the point where the whole motorway slowed to a stop until the caravan and car recovered. The car ended up on the grass verge and the caravan jack-knifed. I stopped as did other drivers to see a family of five with young children sat ashen faced and dazed. No one was hurt, but the driver and his wife were clearly shaken.

His first comments, "The car started wandering in the tramlines and I couldn’t get control of it" .
A Freelander and it also had a stabiliser, which had snapped.

How many more people have experienced this wandering and why aren’t our road surfaces up to it, we know HGV’s use our roads and predominantly the inside lane so why are the surfaces not up to it ? and what does our road tax pay for ?

Just a moan , Merc 808

 

[A-AvantGarde]

How many more people have experienced this wandering and why aren’t our road surfaces up to it, we know HGV’s use our roads and predominantly the inside lane so why are the surfaces not up to it ? and what does our road tax pay for ?

Just a moan , Merc 808

Glad to hear no one was hurt, but that isn't always the case. I've come across this quite a bit in the wet, all I can say is that it's pretty scary when it happens.

I've experienced this on both the M1 & M6. I think that the M6 towards the North West is worse but most of our Motorways suffer from this in the nearside lane.

 

[Brian WH]

Whats a Nearside lane, Iv'e never been in there?

 

[DITTRICH]

Those tramlines are nothing...compared to some of those I saw in Russia. That and the pot holes. Even the potholes had potholes. My approach was to try and find a speed where I tended to 'fly' over the holes and tramlines. Overtaking with these 4'' plus grooves was a bit hairy though.
Les

 

[Shude]

Whats a Nearside lane, Iv'e never been in there?

Try it sometime Brian! On the M62 in the morning it is the fast lane, compared to the stationary middle and outside lanes

Truck drivers are true gents in comparison to reps in poverty-spec BMWs (usual outside lane material).

My 65mph (where possible) drive to work is pleasant and smooth compared to the 80-0-80-0-80-0 of the other two lanes .

 

[PJH]

Probably started wobbling due to slightly different wheel track widths.
Could have happened in the dry too.
People really should have lessons before towing caravans.
If the 'tail wags the dog' the driver should accelerate to stabilize everything, never brake.

Whats a Nearside lane, Iv'e never been in there?

It's over on the left Brian, next to the breakdown lane - I mean hard shoulder.

 

[Brian WH]

Probably started wobbling due to slightly different wheel track widths.
Could have happened in the dry too.
People really should have lessons before towing caravans.
If the 'tail wags the dog' the driver should accelerate to stabilize everything, never brake.


It's over on the left Brian, next to the breakdown lane - I mean hard shoulder.

Not sure accelerating out of a RUT is a good idea, but your principle is sound under any other conditions.

Thanks for the directions, I'll try it sometime when the conditions are right.

 

[A-AvantGarde]

Whats a Nearside lane, Iv'e never been in there?

LOL I try to use it as much as possible, but there are so many people that hog the middle & offside lanes. Sometimes I have to overtake at speeds that I won't / can't mention and then pull back into the far left lane to 'educate' people. Quite often (but not enough) those in the middle lane 'wake up' and get into the left too.

I really hate the start / stop of the offside lane.

 

[weebobster]

This is the very reason I bought my C 220CDi!!!

I used to own a caravan. When towing anything it is advisable to stick to the 85% rule (that is the item/caravan being towed unladen should be no more that 85% the kerb weight of the car towing). Simple physics apply here, and as PJ mentions, if the caravan is too heavey then the 'tail wags the dog'. Some motorists exceed this rule in the mistaken belief that a 'stabiliser' will stop ant resultant 'snake'. Whilst a stabiliser does help, it will not stop a snake brought about by irratic braking, cross wind or 'tram-lines etc etc'. If a snake does develop the best advise (if possible) is to let it subside without braking!!!! Mild acceleration can help too. The reason why i went mercedes (in order to adhere to the 85% rule without going down the 4x4 route) was that my previous car (406 estate) suffered a horrendous snake brought about by a. my speeding and b. cross wind from a passing artic lorry. The snake threw my car into the oncoming lane despite my advice re no braking/acceleration!!!! Thankfully there was no oncoming traffic or wifey/kids/me/other poor motorist would at best be enroute to hospital or at worst enroute to the cemetry. Wifey instantly authorised purchase of Mb (so there is a silver lining to this wee tale of woe) and my enjoyment of all things MB spwaaned forth heheheheheh

....anyway, if you tow remember the 85% rule!!!!!

Check this site out for more detailed info if necessary + be safe!!!

 

[BTB 500]

Apart from the "85% rule" some other basic physics come into towing. The longer the wheelbase of the towing vehicle the better (that's why some offroaders are actually quite poor for towing), and the shorter the rear overhang the better. Both of those are factors in resisting snaking. You also need to have the vehicle's towball at the right height, and the correct nose weight on the caravan. Finally you must load the caravan properly with minimum weight high up and as much as possible near the axle (rather than counterbalanced weight at the front and back ... which acts like a dumbell!). Plus of course the caravan tyres are critical (pressure and integrity - they should be replaced every 5 years or so as the sidewalls start to suffer).

Luckily though in 99% of caravan accidents the only thing that suffers is the caravan itself and occasionally the vehicle towing it. There was some talk of introducing an "MOT" scheme for caravans but the accident statistics simply don't make it worthwhile. The new driving test regs. do require a separate test now for towing anything over (I think) 900 kg.

 

[PJH]

... and the shorter the rear overhang the better.

Yes good point, reduces the amount of leverage the caravan has on the tow vehicle.

 

[Satch]

Law on towing is confusing! Is this still the position?

"There are currently two different sets of rules that govern what you can drive on a Category B car licence without taking an additional test:

Licence gained before 1 January 1997

Entitled to drive any vehicle-and- trailer combination up to 8250kg total weight, of which the towing vehicle’s maximum weight must not exceed 7500kg. This right remains while you still have this particular licence, but is removed if it is withdrawn. This means that if you are disqualified or made to re-take the test you will lose the right to drive heavier vehicles without further testing and will revert to the post-1997 rules

For pre-1997 licences that are still current at 70 years of age, there are some extra medical rules if you wish to renew an existing right to drive vehicle and trailer combinations of up to 8250kg maximum weight.

To keep this entitlement you must take the D4 medical test, which your doctor will charge you for, and you must be able to pass the existing standard car eyesight test. Unless you satisfy these conditions you will also have to revert to the post-1997 rules. Details can be found on the DVLA website (www.dvla.gov.uk). Look for form INF40, also available from post offices or by telephone (0870 240 0009).


Licence gained after 1 January 1997

Restricted to driving or towing with a car (or light commercial vehicle) with a maximum weight of 3500kg. Note this is not the actual weight as loaded, but the vehicle’s maximum allowable weight, or gross vehicle weight, as set by the manufacturers – you will find this in your car’s handbook.

You can tow a trailer or caravan with this licence, but its maximum weight must not exceed 750kg – giving a total possible maximum outfit weight of 4250kg.

If you wish to pull a caravan weighing more than 750kg you must follow the restriction that the maximum allowed weight of the car-plus-caravan combination weighs no more than 3500kg, and that the caravan’s maximum weight does not exceed 100 percent of the car’s unladen weight (this is not the same as the car’s kerbweight)

Yes, if you wish to tow something that weighs over 750kg, you actually end up with a lower total limit for the car-plus-caravan outfit than you would if you were towing under 750kg, where the total can be 4250kg.

If you want to exceed any of the above limits, you need to take a further driving test. For post-1997 drivers, a B+E test (E refers to entitlement to tow trailers over 750kg) can be arranged to give you the same rights as the pre-1997 car driver. "

 

[Dave Lewis]

I used to love those tramlines when I was driving artics. Set the hand throttle, kettle on, nip into the bunk for a nice lie down, truck holds course unaided...........


Actually, they were very dangerous in Eastern Europe, especially when they contained several inches of oily standing water. The unit would aquaplane out of the ruts, while the trailer remained resolutely stuck in the tramlines

 

[Benzowner]

Law on towing is confusing! Is this still the position?

"There are currently two different sets of rules that govern what you can drive on a Category B car licence without taking an additional test:

Licence gained before 1 January 1997

Entitled to drive any vehicle-and- trailer combination up to 8250kg total weight, of which the towing vehicle’s maximum weight must not exceed 7500kg. This right remains while you still have this particular licence, but is removed if it is withdrawn. This means that if you are disqualified or made to re-take the test you will lose the right to drive heavier vehicles without further testing and will revert to the post-1997 rules

For pre-1997 licences that are still current at 70 years of age, there are some extra medical rules if you wish to renew an existing right to drive vehicle and trailer combinations of up to 8250kg maximum weight.

To keep this entitlement you must take the D4 medical test, which your doctor will charge you for, and you must be able to pass the existing standard car eyesight test. Unless you satisfy these conditions you will also have to revert to the post-1997 rules. Details can be found on the DVLA website (www.dvla.gov.uk). Look for form INF40, also available from post offices or by telephone (0870 240 0009).


Licence gained after 1 January 1997

Restricted to driving or towing with a car (or light commercial vehicle) with a maximum weight of 3500kg. Note this is not the actual weight as loaded, but the vehicle’s maximum allowable weight, or gross vehicle weight, as set by the manufacturers – you will find this in your car’s handbook.

You can tow a trailer or caravan with this licence, but its maximum weight must not exceed 750kg – giving a total possible maximum outfit weight of 4250kg.

If you wish to pull a caravan weighing more than 750kg you must follow the restriction that the maximum allowed weight of the car-plus-caravan combination weighs no more than 3500kg, and that the caravan’s maximum weight does not exceed 100 percent of the car’s unladen weight (this is not the same as the car’s kerbweight)

Yes, if you wish to tow something that weighs over 750kg, you actually end up with a lower total limit for the car-plus-caravan outfit than you would if you were towing under 750kg, where the total can be 4250kg.

If you want to exceed any of the above limits, you need to take a further driving test. For post-1997 drivers, a B+E test (E refers to entitlement to tow trailers over 750kg) can be arranged to give you the same rights as the pre-1997 car driver. "

I truly beleive the result of the above new (ish) laws will effectively ban 4x4's from towing caravans. The law works on the MAM maximum allowable mass and as most 4x4's MAM is 3500kgs or higher it don't leave a lot for the caravan

As regards the 85% Rule, there is no such rule. It is advisory only. If you passed your test before 1997, you can almost tow what the hell you like behind your Fiesta

 

[Satch]

Gross Vehicle Weight of my Land Cruiser is 2850kg. A Land Cruiser Amazon GVW is 3260Kg so yes that does limit what you can tow for post 1997 licence holders.

Pity then one of the Amazon publicity shots shows a young looking couple with a f'huge boat on a trailer.....

 

[BTB 500]

If you passed your test before 1997, you can almost tow what the hell you like behind your Fiesta

I thought exceeding your vehicle's braked trailer towing limit or gross train weight was illegal (considered dangerous / unsafe / unroadworthy / whatever) ?

 

[Benzowner]

Bill, it was meant a bit tongue in cheek, but if you look at the maximum towing weights of most Fords, they almost always exceeded the kerbweight of the vehicle or they used to

 

[BTB 500]

Bill, it was meant a bit tongue in cheek, but if you look at the maximum towing weights of most Fords, they almost always exceeded the kerbweight of the vehicle or they used to

No worries.

Max. towing weight greater than kerb weight is not unusual, it just means the vehicle has demonstrated a hill start on a specified gradient with that load on the towbar. So it's a function of torque / gearing / power to weight / traction etc.

With a low trailer (rather than a high-sided caravan) such a setup may be stable enough to tow ... which is presumably why the car makers have endorsed it?

 

[weebobster]

No worries.

Max. towing weight greater than kerb weight is not unusual, it just means the vehicle has demonstrated a hill start on a specified gradient with that load on the towbar. So it's a function of torque / gearing / power to weight / traction etc.

With a low trailer (rather than a high-sided caravan) such a setup may be stable enough to tow ... which is presumably why the car makers have endorsed it?

Your right mate!!!

The police can prosecuted you for a range of offences under the Road Traffic Act if you tow anything which results in you have less than total control of your vehicle. Quite right too!! I wouldnt fancy my wife andkids being in a vehicle that has an uncontrolled car/caravan combi hurdling towards them on the wrong side of the road!!