Welded diffs - VOSA clarification

[drew555]

Under fear of sparking another crapfest, and having no idea which section to put it in (probably not this one, so move it where it really ought to be), I thought I'd leave this here.

The welded diff debate that went on here not so long ago that was full of opinions and fiction prompted me to see if I could get something that wasn't open to debate.

Feel free to disagree with what is here - but I suggest you use the contact details I've left in to get hold of VOSA and tell then that they're wrong because your mate Tel got told by a mate of his who's brother works for VOSA that 'if you get caught with one you'll be sent to Azkaban and your MOT tester will actually eat his own face because it's got a welder' and that they in fact, are doing it wrong - not the zone or their mate Tel.

Here's the convo...

Hi there.

I am currently researching a couple of points of law but am not really sure if you are the people to speak to or not, but this has to be as good a starting point as any.

There have been many spirited debates (on line and off) on the legalities of locked or welded differentials on RWD road cars, with many people citing many different examples on both sides of the coin (those who profess their legality and those who insist they are illegal).

Would you be able to furnish me with a definitive answer to the question:

Are locked/welded/solid axle differentials legal a) for the MOT test and b) for use on the public highway?

We are aware of the handling characteristics a locked differential exhibits, we just want a final answer to what the legal standpoint is.

Many thanks,

Dear Mr Richards,

Thank you for your email enquiry dated 27th July 2012, concerning vehicle
legalities.

VOSA are the governing body responsible for overseeing the MOT test in the
UK. The MOT is a basic roadworthiness inspection carried out on vehicles
to make sure they meet minimum requirements. However, an MOT doesn't
ensure that a vehicle is road legal. A vehicle can pass an MOT inspection
but still be illegal to use on the public highway.

To find out whether the vehicle would be legal on the UK public highway you
would need to address your enquiry through to the Department for Transport
(DfT) as they are responsible for overseeing the 'Construction and Use'
requirements in the UK. They can be reached on 0300 330 3000.

I have contacted the Private Vehicle Scheme Management Policy & Standards
Team relating to the MOT side of things for advice in relation to your
enquiry and you will receive a full response as soon as we have the
relevant information.

I hope this information has assisted you with your enquiry, but if you have
any further questions please do not hesitate to contact us again.

Kind Regards

Rebecca
Customer Service Centre
VOSA Operations Directorate
Tel: 0300 123 9000

Dear Mr Richards,

Thank you for your email enquiry dated 31st July 2012, concerning the
above.

From an MOT perspective a locked diff or "fixed" axle is acceptable. I've
not had experience of them on cars but they are common on quads.

The main concern at time of test is that fixed axles are not suitable for
testing with a roller brake tester and a decelerometer should be used.



I hope this information has assisted you with your enquiry, but if you have
any further questions please do not hesitate to contact us again.

Kind Regards

Rebecca
Customer Service Centre
VOSA Operations Directorate
Tel: 0300 123 9000

FACT - a welded diff WILL NOT fail an MOT.

Next stop is the Department for Transport, I'll update when I have more (unless this thread has also devolved into chaos).

In all sincerity, I hope this helps. Because opinions and fiction helps no-one.

[Barx325i]

What/where the hell is Azkaban?

Yes, we all know it will pass an MOT, you're clearly rattled by this, why are you wasting their time?

[Gibson]

Probably should have waited until we got confirmation from the DfT aswel. Although i already know what the answer from them is (its fine) but it wont be believed by some people on here.

This brings me to my final point. Anyone who has invented an idea of how a vehicle with a welded diff performs in their heads without trying one, please feel free to come and have a drive in my car. Dispelling myth and fiction makes me happy.

[Gibson]

Yes, we all know it will pass an MOT, you're clearly rattled by this, why are you wasting their time?

I can understand that getting told you are A) wrong, and B) An idiot by people who are actually completely and totally wrong would rattle someones cage. I wouldnt have any respect for someone who DIDN'T stand up for themselves in that situation.

[Barx325i]

Yes, we all know it will pass an MOT, you're clearly rattled by this, why are you wasting their time?

I can understand that getting told you are A) wrong, and B) An idiot by people who are actually completely and totally wrong would rattle someones cage. I wouldnt have any respect for someone who DIDN'T stand up for themselves in that situation.

at what point did I say it wouldn't pass an MOT? assumption, general comprehension failure etc is rearing its head again.

[Gibson]

I dont know if you did.

But others did. This is for their benefit.

[Barx325i]

should be interesting to see the DfT blurb

[Gibson]

I agree. I know the answer because i saw a message where it was questioned a while back, but have no proof. So im going to wait for the official word.

[pacerpete]

I dont know if you did.

But others did. This is for their benefit.

When you crash a car with a welded diff and the police accident investigation team discover its presence and notify the insurance company. Try sending the above correspondence to your insurance company and see if they change their mind on making your policy null and void !

A welded diff has no place on a car used on a PUBLIC ROAD.

[Barx325i]

I agree. I know the answer because i saw a message where it was questioned a while back, but have no proof. So im going to wait for the official word.

but again, none of the above were in question, hence asking the OP why he is wasting their time on the back of some one man crusade to prove the world wrong, however in his haste and confusion, missing the target completely.

[Motorhole]

Have never driven a car with a welded/spooled diff, but would like to have a go purely as a matter of interest! I have driven plenty karts and of course they don't have differentials. The initial understeer in wet conditions with slick tyres is frightening the first time but it's easy enough to get to grips with it after a few minutes, but of course this is on a racetrack with lots of room and lots of run-off. In the dry though, karts are just awesome. I do wonder how it would translate to a track car.

The Aussie V8 supercars run spooled diffs as a matter of regulation btw. They do seem to handle pretty well. But LSDs of various sorts seem to be preferable in most forms of high level motorsport (drifting aside), F1 and WRC included, though these days it's computer controlled friction plates. I wonder whether that is from the perspective of adjustability in handling characteristics to suit conditions though.

Nice to know that they will pass an MOT though, either way!

[Brianmoooore]

AFAIK, no one, and certainly not me, has claimed that welded diffs. are illegal to use on the public road. I often use a quad bike on the road, and that has a solid axle and is perfectly legal.
What is illegal, however, is to use a vehicle on a public road that does not have valid third part insurance, and I find it unlikely that any insurance company would insure a 'modification' that imparts a vehicle with dangerous characteristics at lower speeds.
Since the thread that I presume the OP is referring to, I have had further confirmation from someone presumably more senior at Adrian Flux Insurance Services that they will not insure any car with a welded differential.

[sweep]

Wewda=roll up smoker

[drew555]

Tell you what, since you lot already know, I'll just go and find something else to do. It appears that unless someone can provide notarised evidence from VOSA, DFT and an insurance company to the contrary they'll continue to spout fiction. And then will probably find another way to debunk it.

It's nothing more than bigoted zealotry.

But FWIW, I really thought you lot might be interested in the actual truth of the matter - as I was. That's why I was 'wasting their time'.

I tried, and it's apparent that the zone blinkers are still firmly on.

I just sincerely hope that people don't come here expecting to get a reasoned, researched and experienced view on things and not this closed minded idiocy.

Only one question though - how come your man at the insurance company is entrusted but ours isn't?

In fact don't answer that - I already know. Because yours is fictional and agrees with you.

Good luck for the future - sadly, it appears a valuable source of trusted information on the web has disappeared up it's own backside and can no longer be relied upon to give good advice - just biased lies.

Meh. Try to help out and this is what you get.

[Barx325i]

you just can't accept the insurance aspect, and in a desperate attempt to wriggle free with some dignaty, decide to resort to smoke & mirrors, arsing about wasting the time of people at VOSA & DFT.

custard test with regards to your insurance certificate which will list your declared modifications. This would prove a) your insurance co are in fact insuring your welded diff, and b) you're not telling porkies, c) you're insured, and resolve this one for good.

extremely simple

[capri_rob]

Only one question though - how come your man at the insurance company is entrusted but ours isn't?

Where in the original post or any other post on this thread do you say youve checked it with an insurance company ?

You contacted VOSA who told you that a car with an MOT can still be illegal to use on the road - that is no secret anyway.

Your next step would be to contact the DfT - who will probably confirm the same thing

What point are you trying to prove exactly ?

I would expect that Adrian Flux as a well known provider of specialist insurance for modified cars would be a good benchmark as to whether you can get cover for welded diffs or not.

At the end of the day all this seems to have highlighted ( again ) is that if you can't insurer it with the with welded diff declared the car aint road legal.

No offence meant but if you're after a forum thats drift-friendly you're probably in the wrong place

[DanThe]

Id be interested to hear what the DFT says about it

[papercutout]

I've declared a welded diff to the insurance company on every car I've insured with one fitted. I've been with Adrian Flux in the past, and am presently with Sky Insurance - who (when they read it back from their file had it under 'transmission changes' specifying 'locked rear differential'.


Adrian Flux aside, it's insurable, legal, and good to go. I don't get what people's problems have been? (from prior experience, most people aren't claiming they're illegal, just that they're dangerous and 'make you steer into ditches' - which, as many of us can testify, isn't true. I feel this is where the OP's and Drew's arguments are really being aimed.)

Want a photo of my insurance modification list?

[Andyboy]

I have driven an E36 with a welded diff. Absolutely horrid, understeering scrabbling skidding shitbox. Okay for banger racing, a low rent sport replaced by drifting it would appear.

[Gibson]

When you crash a car with a welded diff and the police accident investigation team discover its presence and notify the insurance company. Try sending the above correspondence to your insurance company and see if they change their mind on making your policy null and void !

A welded diff has no place on a car used on a PUBLIC ROAD.

It was proved in another thread that many modified sports and performance insurers will cover a welded diff. If you choose not to declare it then you are an idiot. Because there are insurers that will cover it is therefore PERFECTLY LEGAL

I have driven an E36 with a welded diff. Absolutely horrid, understeering scrabbling skidding shitbox. Okay for banger racing, a low rent sport replaced by drifting it would appear.

Or, the most fun you can have with your clothes on. Honestly, dont knock it until you have tried it. Then you are perfectly within your rights to tell us it is shit, until then you are just inventing shit on how you think it might be. Ive known plenty of people who have been sceptical and totally converted after being pursuaded to attend a drift day. Let me guess, the car you drove was slow speed around a car park in tight circles, yea, thats gonna sound a bit shit but certainly isnt dangerous. At speed in a car with a welder its either totally unnoticeable or more predictable than an open diffed car. If it does start to step out (and dont pretend open diffed cars dont occasionally) a welder will predictably and smoothly step back in when you let off the throttle, unlike the tendency of an open diffed car to lock one wheel, keep spinning the other and throw you back the other way resulting in a massive tank slapper.

[Barx325i]

An off the shelf locked diff maybe, but a diff you welded up in your shed, pull the other one

[pacerpete]

It's a lifestyle, man !

[Barx325i]

angrydrift.net

[Gibson]

An off the shelf locked diff maybe, but a diff you welded up in your shed, pull the other one

Im not pulling anything good sir. This is all correct information and you obviously get someone who knows what they are doing to weld it in the correct manor. Dont want it to be dangerous obviously

angrydrift.net

Pretty rich coming from http://www.BlinkersOnWontListenToAnyoneFuckingElseEvenWhenTheyAreProvedRightZone.net.

[Gibson]

Oh and for whats its worth, i questioned how safe it was when i first heard about welded diffs (on here actually) You could go through my old posts and have a look if you wanted. I am now converted from being a bit like you lot to understanding how they work/drive.

[pacerpete]

An off the shelf locked diff maybe, but a diff you welded up in your shed, pull the other one

Im not pulling anything good sir. This is all correct information and you obviously get someone who knows what they are doing to weld it in the correct manor. Dont want it to be dangerous obviously

angrydrift.net

Pretty rich coming from http://www.BlinkersOnWontListenToAnyoneFuckingElseEvenWhenTheyAreProvedRightZone.net.

Sorry mate , you are seriously mistaken if you think any of us give a foook what you do with your sorry scrap.

Weld the diff /slam it / cover it in stickers / drink Redbull / drive around in circles et al, crack on. It is not as if you are ruining nice cars, they are generally scrap by the time you boys get them

[HairyScreech]

Fucking hell here we go again.

Lock this one up its going to go round in circles.

[Kos]

to me what makes no sense at all is that a car can pass an MOT and still be illegal for highway/road use.

for me this needs to be addressed first. an MOT should mean a car is legal for use on the road.

you have similar issues but the other way round with harnesses. they will fail an MOT in some cases but are legal for road use.

its totally fucked as some cars come with only harnesses fitted

[gooner1]

Surely a simple question, re the modded diffs, to the Zones resident insurance brokers, Sky,
would go some way to settling this?
Having never driven a car with a welded diff, my mind is completely open.

[Andyboy]

When you crash a car with a welded diff and the police accident investigation team discover its presence and notify the insurance company. Try sending the above correspondence to your insurance company and see if they change their mind on making your policy null and void !

A welded diff has no place on a car used on a PUBLIC ROAD.

It was proved in another thread that many modified sports and performance insurers will cover a welded diff. If you choose not to declare it then you are an idiot. Because there are insurers that will cover it is therefore PERFECTLY LEGAL

I have driven an E36 with a welded diff. Absolutely horrid, understeering scrabbling skidding shitbox. Okay for banger racing, a low rent sport replaced by drifting it would appear.

Or, the most fun you can have with your clothes on. Honestly, dont knock it until you have tried it. Then you are perfectly within your rights to tell us it is shit, until then you are just inventing shit on how you think it might be. Ive known plenty of people who have been sceptical and totally converted after being pursuaded to attend a drift day. Let me guess, the car you drove was slow speed around a car park in tight circles, yea, thats gonna sound a bit shit but certainly isnt dangerous. At speed in a car with a welder its either totally unnoticeable or more predictable than an open diffed car. If it does start to step out (and dont pretend open diffed cars dont occasionally) a welder will predictably and smoothly step back in when you let off the throttle, unlike the tendency of an open diffed car to lock one wheel, keep spinning the other and throw you back the other way resulting in a massive tank slapper.

Well, if that's the most fun you've ever had.........

I've seen real drift heroes do it in cars with open diffs so perhaps you should take your undoubted skillz to the next level - go on, expand your horizons a little.

[papercutout]

An off the shelf locked diff maybe, but a diff you welded up in your shed, pull the other one

No offense, but that comment is incredibly stupid. Yes, a diff with a tiny bit of weld thrown in is dangerous, as it's liable to break and lock, that is common sene. If it is done properly (regularly people will cut a plate to fit between the teeth and weld that in, and I have NEVER heard of that breaking - one of my friends puts his reputation on it, and has never had one break) then it will function identically to an 'off the shelf locked diff', with no adverse properties.


As for Andyboy, the understeeryness is down to cheap tyres. I've run cheap tyres on the front, and it's aweful, the present car has Parada Spec 2's on the front though, and I don't get understeer. But then, that's like a car with an open diff really isn't it?

[Barx325i]

An off the shelf locked diff maybe, but a diff you welded up in your shed, pull the other one

No offense, but that comment is incredibly stupid. Yes, a diff with a tiny bit of weld thrown in is dangerous, as it's liable to break and lock, that is common sene. If it is done properly....

None taken, I'm wondering what engineer will sign off said welded up open diff as sound for use on a public road / insurance purposes?

[scjimbo]

An off the shelf locked diff maybe, but a diff you welded up in your shed, pull the other one

No offense, but that comment is incredibly stupid. Yes, a diff with a tiny bit of weld thrown in is dangerous, as it's liable to break and lock, that is common sene. If it is done properly....

None taken, I'm wondering what engineer will sign off said welded up open diff as sound for use on a public road / insurance purposes?

I wouldn't

[yung-gun]

I live in north wales and i know an ex traffic sergeant. I asked him and he said he didn't know so he would ask the powers that be (angelsey's traffic division) He cam back to me and said they are legal but why would you want one it'll only eat through your tyres.

Happy to say the welders coming out this weekend

[yung-gun]

I also rang Sky And Adrian who both said they DO cover welded diff's