Disco 2 V8 Towing

[Grumndriva]

My wife and I are considering buying a 20 foot caravan which will weigh in at close to 2400kg when loaded. The tow vehicle is a 4.0 litre automatic in sound mechanical condition. Based on our experience towing a camper of half that weight, I am concerned at the Disco V8's lack of torque when it comes to hills.

Anyone have any experience towing that sort of weight with a 4 litre V8?

Cheers,

Terry

[Taz]

Crikey! I dream of the torque in a V8 D2 auto for towing. Try towing your van up hills with a Tdi - and I know a few mates who happily do exactly that and are quick to tell you what economy they are getting, but not how fast they go up hills. I think I understand where your coming from - not wanting to hold up traffic up long hills, however the 340Nm of the D2V8 should be well above your average jap tow beast, especially because the torque is produced at low revs (2400 from memory?) which the jap vehicles cannot match (unless it's a twin hair drier LC v8 diesel worth 4x as much as your D2).

[tempestv8]

Hi Terry,

I tow a 1100 kg Jayco Hawk Outback plus about another 200 kgs of various bits and pieces, and the 4.0 Disco II V8 auto struggles up the hills that you will find on highways like the Hume. And if you fit larger tyres like 32" diameter tyres (Land Rover DII has 29" diameter tyres as standard regardless of wheel size) you'll find that your acceleration will be blunted even more.

Approaching big hills, the cruise control needs to be turned off because the engine will rev itself nuts when the gearbox downshifts from top gear, torque converter locked to 3rd gear or even 2nd gear. It's not uncommon to need 4000 rpm or high to get up some of those hills. You'll need to have ear plugs when the engine revs its head off, and also a big credit card, because the motor will chew its way through a LOT of fuel. Expect your fuel consumption to be bad. I estimate it will blow out to around 24-25 litres per 100 kms on 95 or 98 octane RON or close to 30 litres per 100 kms on LPG.

Also expect your cooling system to be worked to the limit. If your cooling system is less than adequate, I suggest very strongly that you fit an aftermarket early warning system in the event of low coolant. A friend of mine has also fitted a transmission fluid temperature gauge and it is most interesting to see how much the fluid temperatures fluctuate. When the torque converter is unlocked, the fluid heats up very quickly. So be sure that your auto trans oil cooler is clean and not clogged up with dried up mud, if you happen to like visiting bog holes!

The V8 makes the most torque around 2700 rpm, so I'd just leave the gearbox in 3rd gear most of the time. The beauty of the ZF4HP22E gearbox is that it has lock up capability in 3rd gear as well as 4th gear, so it's not going to be as savage on your fuel consumption as on the Disco I, which I believe does not lock up in 3rd gear (only top gear).

One solution is to fit a 4.6 litre V8, to the Disco, which makes the job a lot easier, although there is no appreciable fuel economy gains.

Personally, if I were in your shoes, I'd buy a different vehicle which will tow better. Unless you are not in a big rush. Often I find that if I'm towing on my own, it's not so much of a challenge but if travelling in a convoy, there's the need to keep up with the rest of the pack, and most of my mates are driving more powerful tow vehicles....

Lawrance

[Blknight.aus]

the td5 is my tow motor of choice...

but the v8 well tuned and breathing nicely will haul up hills like you wouldnt belive. the wind resitance and balance of your trailer will be of more concern than the weight.

hell even the 3.5l carbied rovers used to climb like elevators if you were willing to stick the boot in, cog down one and watch the fuel gauge go down faster than a space shuttle.

[RonMcGr]

My wife and I are considering buying a 20 foot caravan which will weigh in at close to 2400kg when loaded. The tow vehicle is a 4.0 litre automatic in sound mechanical condition. Based on our experience towing a camper of half that weight, I am concerned at the Disco V8's lack of torque when it comes to hills.

Anyone have any experience towing that sort of weight with a 4 litre V8?

Cheers,

Terry

Terry,

Your concerns are well founded.
We tow a 15' van behind a D1 V8.
One word, "Gutless".
Have to use third gear to get going above 80kph and change into top at 90 kph.
The torque band id far too high.
Different cam and it maybe better.

Last weekend, there was a guy at the Esk CP with a new Range Rover twin turbo diesel V8, towing a 2.8tonne huge Boroma van. The bugger gets 14l /100km towing and 5.8 on it's own. He traded a Toyota LC V8 on the Rangie and is rapt!

Be nice to have the money.

Pic attached.

[PhilipA]

I am a little bemused by this post.
Surely everyones perception of "gutless" is different. The Poms think a 3.5 is a great tow vehicle.
My question is- Is it a 2001 Disco 11 or is it earlier.
The Thor 4Litre has a completely different torque curve to earlier cars.
The Thor High compression of 2003 will have more power and better fuel economy again.
I have an old RRC 3.9 to which I have fitted a Thor manifold and had dyno tuned and a Unichip, among other things. Mine will hold 4th gear climbing Mt Ousley near Wollongong (which is one of the steepest highway hills in Australia) towing my 600KG camper trailer. I have never been passed on a hill even by a Cruiser diesel towing a camper .
So I believe that even a 4.0 litre V8 will tow a 2400KG caravan easily. you may have to hold third gear manually on highway hills or even second on the few really big hills, but the revs your V8 can attain compared to a diesel will enable you to keep to a reasonbable speed.
If you have non Thor 4.0 litre, $2-3K spent on a Thor conversion and piggyback chip will transform the car.
Even though you will spend more on petrol , the cost will be far less than changing cars.
Regards Philip A

[Grumndriva]

Hi Philip,

It is a 99 Series 2. It works very hard pulling our Penguin Outback (which is probably around 1200 to 1300 kg loaded) on hills, and the only option is to lock it in third or even second and let it rev its little heart out. I seriously doubt its ability to cope with an extra 1000 kg, hence my post.

Thank you for your response.

Cheers,

Terry

[Taz]

Sorry to hijack your post Terry, but Philip - I was just wondering what the theory is behind the Thor manifold? Is it variable intake lengths or something tuned in such a way that the intake pulses hit resonance or simply don’t interfere with each other, hence getting a greater charge into the cylinders?

[Psimpson7]

adding to the post about the 3.5 being regarded as a decent tow vehicle in England!

I have a late low mileage 3.9 classic Vogue SE Manual and it is, in all honesty rubbish towing a trailer, unless you thrash it.

My TD5 will walk away from it any day of the week.

Having said that, 2500kgs isnt that much and we have extensivley towed loa ads up to 3500kgs with 3.5carb auto, 3.9efi manual, td5 d2 automatic, td5 manual 90, and tdi manual D1, and they all managed ok, but driving style had to be changed to suit. I cant speak for the later 4.0 but it should be better than the earlier ones.

I would say the TD5's were easily the best.

Rgds
Pete.

[shouldownacruiser]

Well there seems to be a big divergence of opinion which must have something to do with the variance in models and years. I have a late 02 v8 auto ES (large rims, low profile tyres) and I have towed an old 19 foot caravan with it and I found myself easily overtaking tradie utes going uphills. I could hold the speed limit (or very close to it) up most hills without too much hassle save for the appalling fuel consumption.