# FWD v RWD



## motormouth (Jul 3, 2010)

Which is best, FWD or RWD.
Apart from the obvious weight benefits, any other reasons why one is better than t'other??


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## cabby (May 14, 2005)

There is no better than in this case, it is just a case of choice.one has different driving aspects than the other.lots of us have reasons to prefer one or the other.

cabby


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## stearman65 (Nov 22, 2010)

*FWD RWD*

In my case FWD which has enabled me to get over 6ft headroom in my Renault Trafic self build. RWD raises the rear platform on a cab/chassis make up AKA Transit.
Stearman65


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## steco1958 (Mar 5, 2009)

FWD / RWD, would be way down my list of important aspects of a MH, I would be more concerned about the layout and how that fits in to how I want to use the MH.

Steve


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## drcotts (Feb 23, 2006)

RWD is generally thought to be better for grip and getting of wet/muddy campsirtes and fields as therev is more weight over the wheels.

Most Mercs are RWD (arent they)

Phill


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## JeanLuc (Jan 13, 2007)

Both formats have their advocates.

Ours is RWD and I would not want anything else. I have read many posts by disgruntled drivers of FWD motorhomes who cannot get traction on wet grass, let alone a bit of mud. Given that most of the weight of a motorhome is towards the rear, and this is most pronounced if the van has a large overhang, the downward force on the front wheels can be quite low. A light front end, FWD and a slippery surface do not make for good traction. I have heard owners of Ducato-based motorhomes refer to the ease with which they can spin the front wheels on damp tarmac.

We have just spent the weekend on a CS in Ripon. Our departure on Monday was through 4" of snow, up a narrow farm track with a gentle incline. We pulled away and out with not even a tremor of wheel spin. I do not think a Fiat-based motorhome would have managed it so easily.

Philip


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## stevee4 (Oct 12, 2007)

*Rear wheel drive please*

I have had 3 FWD MHs. How ever I have a RWD BMW. I specifically looked for RWD when buying my car and the Beamer delivers ooooooooooodles and oooooooodles of grip. Especially if you know how to get it. I am lucky enough to have had masses of advanced professional driving tuition. There is NO comparison. 
I cannot believe how MH companies continue to blindly go down the FWD ducato base vehicle.

Please can we have more twin wheel RWD base vehicle please. It will get rid of the need for tag 2 axle and massive rear overhang & FWD.

You know it makes sense!!!


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## Rosbotham (May 4, 2008)

JeanLuc said:


> Given that most of the weight of a motorhome is towards the rear, and this is most pronounced if the van has a large overhang, the downward force on the front wheels can be quite low. A light front end, FWD and a slippery surface do not make for good traction.
> Philip


I've heard that said myself in the past, but I'm not sure I buy it. I've not got my weighbridge figures in front of me, but from memory for my motorhome it was c1900kg front, c2100kg rear...there's not a great deal in it. I _would_ say that if you're on the point of spinning, have the steering through the driving wheels isn't the best idea.

What's probably more material is that RWD is often combined with twin rear wheels.

As others have said, habitation layout is the primary consideration for me.

Paul


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## rupert1 (Feb 13, 2009)

*Re: Rear wheel drive please*



stevee4 said:


> I have had 3 FWD MHs. How ever I have a RWD BMW. I specifically looked for RWD when buying my car and the Beamer delivers ooooooooooodles and oooooooodles of grip. Especially if you know how to get it. I am lucky enough to have had masses of advanced professional driving tuition. There is NO comparison.
> I cannot believe how MH companies continue to blindly go down the FWD ducato base vehicle.
> 
> Please can we have more twin wheel RWD base vehicle please. It will get rid of the need for tag 2 axle and massive rear overhang & FWD.
> ...


The BMW bit simply cannot be correct, the more weight over the wheels the more grip. With a car the grip does depend a lot on the conditions, tyres fitted and driver skill but all being equal a FWD car will always give more grip. Motorhome differant as weight is usually over the rear and so FWD will give less grip but again a lot will depend on others factors as with a car. The reason a FWD M/H is prefered is, as been pointed out, the better layout that a fwd will offer, no propshaft or rear diff. to get in the way. If, like Paul, your weight is pretty even makes no differance the amount of grip will depend on the driver skills, tyres bit. I should say that I think we are talking traction here rather than grip.


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## viator (May 1, 2007)

The best motor by a mile that I have owned for winter conditions was a VW T3, rear engine/wheel drive(with appropriate tyres).
viator


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## rowley (May 14, 2005)

Rupert wrote--I specifically looked for RWD when buying my car and the Beamer delivers ooooooooooodles and oooooooodles of grip.

I don't think that my neighbour would agree with that. BMWs, including his were stuck on a snowy incline this week, FWD cars were going past them.

My Citroen Relay coped with snow on an incline quite well last year, but it is a panel van and does not have the overhang problem.


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## viator (May 1, 2007)

My first experience of front wheel drive was a Citroen Light 15 in 1955, the one with the gear lever sticking out of the dash, it went round corners like it was on rails. I was also delivering cars from Cowley in the early days of British made FWD and in snowy conditions they were superior to RWD. This was proven time and again by Paddy Hopkirk and the Mini Cooper, notably in the Monte Carlo.
My own FWD panel van is as good as any similar size RWD van, as I have proved during last winter and this winter.
FWD in larger vans, ie coachbuilts to me do not have the best balance of load and traction. 
viator


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## Rosbotham (May 4, 2008)

Yup, my Jag's firmly locked in the garage until this weather shifts. 420BHP, rear wheel drive, no weight over rear wheels....not a good mix in this kind of weather.


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## SaddleTramp (Feb 15, 2007)

This year when we left UK for touring Hols I had a FWD Autotrail 3.0 I boarded ferry at Hull, On boarding the front wheels were skidding like mad cos the ramp was wet, They ended up putting ropes down for 4 of us to allow us to board. 

So my new one is RWD.

Not just because of this incident but a number of things including weight and this.


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## moby56 (Sep 16, 2010)

As long as you know how to drive and control the revs it makes little difference both types of drive are OK


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## teemyob (Nov 22, 2005)

*RWD*

Propulsion rather than Traction.

RWD is best for motorhomes, how many FWD Trucks are there?.

RWD Is also better for towing

RWD Motorhomes, tend not to get stuck on wet grass

RWD Motorhomes with twin wheels are better still, think of it as a 4x6

I would only choose FWD as a last resort.

If you want ALKO with RWD, you can have this too.
***************************************

TM


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## smick (Jun 1, 2005)

I'll go long with that Trevor - and add 

"And Mercedes are RWD"

QED.


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## CliveMott (Mar 10, 2008)

Rear wheel drive is good because :-
Drive is on on the axle with most weight.
Frequently drive is on 4 out of 6 tyres on bigger vehicles.
Steering lock is significantly better allowing tighter turning circles / easier parking.
No constant velocity joints to bother about.

Front wheel drive is good because :-
Complete power train is contained in one unit.
Overall cost of power train is lower.
Lower floor levels possible because no prop shaft underneath.


C.


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## safariboy (May 1, 2005)

With front wheel drive all the mechanics are assembled in one sub-assembly. This simplifies manufacture and must cost less. I am sure that that is why most vehicles are front wheel drive.


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## drcotts (Feb 23, 2006)

Rosbotham said:


> JeanLuc said:
> 
> 
> > Given that most of the weight of a motorhome is towards the rear, and this is most pronounced if the van has a large overhang, the downward force on the front wheels can be quite low. A light front end, FWD and a slippery surface do not make for good traction.
> ...


That 400 plus pound over the back wheels has to be pulled out of a rut by the front when on a muddy field and thats what does it. The rear wheels sink in - only a bit - but the front wheels then have to try and drag these out. And if your on a little upward incline the moments of force make it worse. Its not a lot to do with what the weight is but more where the weight is.
O got stuck on a field in cornwall once in my fiat glendale. The bloke who towed me out had big recovery RWD truck which must have weighed half as much again as my van but he drove across the field as if it was tarmac, dragged me with him on a tow rope and charged me 25 quid for a 25 yard tow.

Phill


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## barryd (May 9, 2008)

I would prefer rear wheel drive and twin wheel as well for more payload and better traction however did I read somewhere on here that rear wheel drive motorhomes tend not to have double floors and are not therefore properly winterised or is that just complete rubbish. 

I would always want our same front dinette and rear U shaped lounge but Im not sure such a vehicle exists in rear wheel drive.

Anyway as far as getting stuck on grass, thats what tuggers are for isnt it? Gives them something to do when they get bored of playing with the industrial size awning.


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## seamusog (May 10, 2005)

I have to agree with Rupert1, BMW's/Mercs are hopeless in the snow,no matter how good a driver you think you are,I've have had at least eight BMW's, now on my third Merc, present one is an S Class, a big useless lump of tin which is sitting in my driveway, with four bags of sand in the boot, going nowhere.

I have been driving for fifty years,loads of experience driving in snow, but I cannot get my Merc out of the driveway. The neighbours, with thier corsa's and Clio's are having a good laugh at my endeavours as they glide effortlessly through the white stuff.
seamus.


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## teemyob (Nov 22, 2005)

*Drive*



moby56 said:


> As long as you know how to drive and control the revs it makes little difference both types of drive are OK


Does not matter how well you know how to drive or control the revs. A large FWD MOTORHOME will get stuck in the mud/snow or even damp grass, long before a RWD. That is what the Pro RWD are pointing out in response to the posters question.

Just like the poster who could not drag his FWD outfit onto ferry.

Yes, many say a FWD is a RWD if your reverse. I can't reverse all the way around Norway, the Alps or Pyrenees. Hence, one of the reasons I chose RWD.

TM


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## JeanLuc (Jan 13, 2007)

barryd said:


> did I read somewhere on here that rear wheel drive motorhomes tend not to have double floors and are not therefore properly winterised or is that just complete rubbish.


It depends on the motorhome - if it's a Hymer (on a Merc chasis) it has a single floor and is well winterised. We have just been away for the weekend in N Yorkshire. Never got above freezing the whole time, - 10ºC overnight and no problems. We were warm inside, all the pipes worked perfectly and the water in the waste tank was still steaming when I emptied it at home.

Now some single floor UK vans are a different proposition entirely and I wouldn't want one for use in the winter.

Philip


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## teemyob (Nov 22, 2005)

*BMW/Mercs*



seamusog said:


> I have to agree with Rupert1, BMW's/Mercs are hopeless in the snow,no matter how good a driver you think you are,I've have had at least eight BMW's, now on my third Merc, present one is an S Class, a big useless lump of tin which is sitting in my driveway, with four bags of sand in the boot, going nowhere.
> 
> I have been driving for fifty years,loads of experience driving in snow, but I cannot get my Merc out of the driveway. The neighbours, with thier corsa's and Clio's are having a good laugh at my endeavours as they glide effortlessly through the white stuff.
> seamus.


I too have had BMW's and Mercedes Cars, including an S Class. They were never stranded because of Snow/Ice as I have always used winter tyres, all year.

Last winter I drove up a hill in my Wife's Audi A2 (FWD - Winter Tyres) passing 4 people trying to push a BMW X3 up the hill with the tyres spinning and stopping.

On the way down, one of the blokes stopped me in the road and asked how I the hell I got up the hill. Simple, I have winter tyres. I also pointed out that he may have more luck getting the Beemer up the hill if the turned the DSC off!

Back to FWD: My Daughter's Audi A3 (2010 model year) is lethal in this weather running on Michelin Summer tyres. Will be fitting winters at weekend, Something I told her to let me sort out weeks ago.

But as we are talking motorhomes here. As I said, larger motorhomes are best suited to RWD chassis.

TM


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## teemyob (Nov 22, 2005)

*Rubbish*



barryd said:


> I would prefer rear wheel drive and twin wheel as well for more payload and better traction however did I read somewhere on here that rear wheel drive motorhomes tend not to have double floors and are not therefore properly winterised or is that just complete rubbish.
> .


Yes it is complete rubbish.

We have had two Mercedes motorhomes, both winterised and both with heated double floors.

If you want rear wheel drive and and alko chassis, you can have that in a Mercedes too. You can also buy a Tag Axle Mercedes RWD.

TM


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## barryd (May 9, 2008)

*Re: Rubbish*



teemyob said:


> barryd said:
> 
> 
> > Yes it is complete rubbish.
> ...


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## teemyob (Nov 22, 2005)

*Re: Rubbish*



barryd said:


> teemyob said:
> 
> 
> > barryd said:
> ...


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## barryd (May 9, 2008)

Dont care if its pink if it meets those requirements.

Specific models anyone?


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## teemyob (Nov 22, 2005)

*van*

as posted by grommet

Slip sliding away

I am off to do some work in my RWD Car, thick snow an ice here. I have to go up into the hills.

Pray for me.

TM


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## grizzlyj (Oct 14, 2008)

Hi

From a physics point of view the force required to just make the tyre slip is purely dependant on the friction of the meeting surfaces and the weight pushing them together. A loaded truck on tarmac vs an empty luton van on grass, its obvious which wheels will spin!

Whichever axle has the most weight will have the most grip if they have the same type and size of tyres on the same surface.

If a rear wheel drive camper has more weight on that axle it will have more grip but only because of that weight. Add a second tag axle to spread the load and you are reducing the grip available to each tyre for that weight. You may not sink, but you may not go anywhere either 

For that given amount of resistance to tyre slip (or grip) it get used up in several ways. There is only a certain amount of grip in total, as above, decided by the friction between the materials and the weight only.

The tyre may have to brake, accelerate or transmit a sideways force (front or rear) with that fixed amount of grip.

So a front wheel drive has to change the vehicle direction and its acceleration/deceleration with its axles grip. A rear wheel drive obviously splits this, freeing more grip to braking and steering on the front axle. So a rear drive BMW doesn't have more grip available at all (and could only increase it with a bigger tyre footprint or more weight. (Or tractor tread in mud, chains in snow, slicks on dry tarmac, spikes on ice etc)), it is just more able to better use the grip it has by splitting jobs between front and rear.

F1 cars are rear wheel drive (and any decent handling sports car) for this reason. F1 cars increase weight and therefore grip by downforce. Braking is always done in a straight line before the turn unless the corner speed is high enough to maintain downforce which maintains sufficient weight on the front wheels for them to brake and turn.

Slow speed corners are harder because the downforce drops off to nothing below perhaps 80mph. If the front tyres are carrying 2 tons at 180mph, they will only have perhaps 400kg at the slow hairpin just after the biggest braking section and then the tightest turn, but with least grip, so cars often sail straight on with insufficient grip to still be slowing down and then turn.


So a RWD camper will overall make more use of its available grip. 

Once you've lost that grip on ice etc, then having the front wheel driven tyres pointing and pulling in the direction you want to go saves the grip available to that tyre for motion in that direction. 

RW driven wheels only push forward, which if thats not where you want to go mean the steering tyres are fighting them (rather than just coming along for the ride like the rear wheels on a FWD in ice would be), and using grip to do so, leaving you with less directional control. Pulling out of a muddy rut is always easier if the front tyres are pointing forwards, not trying to change direction too.

Jason


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## rupert1 (Feb 13, 2009)

rowley said:


> Rupert wrote--I specifically looked for RWD when buying my car and the Beamer delivers ooooooooooodles and oooooooodles of grip.
> 
> I don't think that my neighbour would agree with that. BMWs, including his were stuck on a snowy incline this week, FWD cars were going past them.
> 
> My Citroen Relay coped with snow on an incline quite well last year, but it is a panel van and does not have the overhang problem.


I certainly did not write that, suggest you look again.


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## teemyob (Nov 22, 2005)

grizzlyj said:


> Hi
> 
> .
> 
> ...


Agree with almost everything you say Jason.

But putting a bigger footprint on by way of bigger tyres will make things worse in mud and snow.

This is why Big 4x4 with low profile tyres get stuck. Whereas the ones with standard tyres (think BMW X5 Sport v the standard BMW X5) and the little FWD or RWD cars with narrow tyres don't.


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## DTPCHEMICALS (Jul 24, 2006)

I have been stuck in mud once. Donnington Park a couple of years ago at Moto Gp. Thats in 5 years with mh.
So if that is the regularity of getting stuck in mud the FWD will do for me.

Mind you mh is stuck today behind heaps of snow at abot 4 feet high. :lol: 


Dave p


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## EEVpilot (Aug 15, 2010)

My vote is that traction will be better on the rear drive vehicles. FWD vans, like my own Ducato do spin the wheels easily, they require traction control systems, similar to a car, to be more effective and few (if any) of them do.
The main benefit for the driver will be the improvement in steering provided by rear drive. The steering no longer has any negative influence caused by engine torque (torque steer) which can be quite alarming if trying to pull away quickly and turn simultaneously. Under these conditions the steering does not self centre - not good for smooth progress!!!

The benefits for front drive, even with the negatives I have mentioned, have been answered already, weight, layout etc. They remain very valid for MH's and I am prepared to live with my FWD 'van for this reason.

As for BMW's (I have one) no use in the slippy stuff ....ours spends a lot of winter in the garage resting, leaving the real work to the true master.....All wheel drive  

John


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## teemyob (Nov 22, 2005)

*Models*



barryd said:


> Dont care if its pink if it meets those requirements.
> 
> Specific models anyone?


Models - Click here to go to my post - Then click "In English' There

If you want to see a rear lounge, look in my Garage at the foot of my post.

Let me know if you need any help or info.

TM


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## grizzlyj (Oct 14, 2008)

teemyob said:


> Agree with almost everything you say Jason.
> 
> But putting a bigger footprint on by way of bigger tyres will make things worse in mud and snow.
> 
> This is why Big 4x4 with low profile tyres get stuck. Whereas the ones with standard tyres (think BMW X5 Sport v the standard BMW X5) and the little FWD or RWD cars with narrow tyres don't.


I disagree!! 

That is a kind of it depends sort of thing I would think? 

Little old Landies used to come with I think 6.5 * R16 tyres which were a teeny diameter (maybe 27/8"?) and narrow. You could also have 7.5 * R16 which were often about 32/33" tall and wider. A similar difference to your X5's. Mostly these were better in mud for the weight of the Landy. Put them on a fully loaded LWB and you may well still sink. On an empty SWB you may not have enough grip with too much flotation. I had 33"*12.2 R15 mud tyres on a light CJ7 Jeep which on sloppy mud or soft sand were ace, but on the clay slopes around Arena Essex were dangerous.

My current Unimog has tyres about 46" tall with a 395mm section. At road pressure there is about 5" of tread length on the road, at 10psi there is 24" of tread length.

So depending how soft or hard the ground is everything I would think has an "ideal" footprint size to maximise traction without sinking?

This vid has a LR 101FC and a Unimog 404 trying to pull a U1600 Unimog on grass. So 8*8 vs 4*4, the U1600 has 1500kg more than the other two but less power, who wins? (Twice!)






Jason


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## rowley (May 14, 2005)

I apologise to Rupert for making a quote which someone else on that page had made. PM on it's way.


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## moby56 (Sep 16, 2010)

Sat this morning watching my dear little wife drive off to work in her little FWD, bloke over the road stuck on drive !!!! :lol: with his RWD using too low gear and too much revs years of driving in proper snow conditions in Germany :lol: :lol:


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## PaulW2 (May 30, 2010)

Not sure about the MH argument (mine is a Boxer-based FWD) but I find FWD cars are much superior in the snow and ice. Maybe the different weight distribution of motorhomes makes a difference in favour of RWD.

I have a Merc (RWD) which weighs about 1,700 kg and it's quite useless in the snow. My daughter's little Fiat 500 is much superior. 

When the roads aren't slippery, the RWD characteristics are however of course great...


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## teemyob (Nov 22, 2005)

*My RWD*

My RWD Car is superb in the Snow/Ice/Mud

Toyota Previa 2000 Model


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## rupert1 (Feb 13, 2009)

*Re: My RWD*



teemyob said:


> My RWD Car is superb in the Snow/Ice/Mud
> 
> Toyota Previa 2000 Model


Ah! but this has an engine under the floor so weight is pretty even. I once had the Jap import version of this, Toyota Estima, which was 4x4, used it in the alps for a season, great for transporting six people around.


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## rupert1 (Feb 13, 2009)

rowley said:


> I apologise to Rupert for making a quote which someone else on that page had made. PM on it's way.


Absolutely no need, we all make mistakes, me more than most but thanks anyway.


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## teemyob (Nov 22, 2005)

*Re: My RWD*



rupert1 said:


> teemyob said:
> 
> 
> > My RWD Car is superb in the Snow/Ice/Mud
> ...


I know someone would suss it!

But at the end of the day, Still RWD

As is my other one.


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## PhilK (Jul 1, 2005)

*FWD/RWD*

It really doesnt matter which one you have if you want to get off a muddy field. That is all about traction, and front wheel drive has the engine and fuel tank over it, so why do people believe that the RWD has weight over it? The answer is that under acceleration, you get a weight transfer to the rear, inertia, but if you are doing 1 mph this does not apply. Advanced driving as stevee says is useful, but unless its included off road, then most advanced is not going to help you on a field.

A good counter argument to RWD is that with FWD the driving wheels are always pointing in the resultant direction of the vehicle, rather than being pushed around a corner or across a field. This increases tyre life and avoids stresses on hubs and tracking rods.

Phil


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## teemyob (Nov 22, 2005)

*Factors*

Lots of Factors involved Phil

A Front Engine delivery van is best with RWD when full. But empty, be better of with FWD.

As for tyre wear, never had a RWD that wore tyres more then FWD. My RWD vehicles have tyres that last at least 40,000 miles, some many more.

I recommended RWD for larger motorhomes. Better still, RWD with twin rear wheels making the vehicle a 6x4.

If you have got crap tyres, don't really matter what drive you have, will be useless on anything but dry tarmac.

TM


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## PhilK (Jul 1, 2005)

*RWD/FWD*

Points taken Teem. I have done an MB and a VW van driving day as well as a Renault one. We get invited every time they launch new vans as we supply 250 to 300 new vans a year. The Renault day is probably the most neutral as they have both RWD and FWD. Interestingly the drivers took the vans through a muddy test site and reckoned there is nothing to choose. These being unloaded, new tyres etc. The most important thing they all do, without fail, is to press the brake and accelerator at the same time, the result being that the diff is fooled into thinking that both wheels have traction and driving both. Done with skill, this technique can achieve more than all wheel drive in a car (as an appose to 4WD) 
In a larger motorhome, RWD distributes the weight more evenly across the whole van, as traction and fields are not all we have to think about. I would subscribe absolutely to you thoughts here, though below 3.5 tonnes I can see man merits of FWD, no least the new lower Fiat floor.

Cheers TM

Phil


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