It’s no surprise that a survey of members of the Society of Motor Manufacturers and Traders (SMMT) saw a huge majority (77 per cent) in favour of remaining in the EU, with only 9 per cent saying leaving would be best.

Notably no major auto assembler in the UK has said that an exit would be in their business’ best interests.

As the SMMT has pointed out, the auto industry is important for the UK economy. The sector supports 800,000 jobs across the UK and contributes £15.5 billion annually to the economy.

UK car production is currently at its highest level for over a decade, up by over 60% since the financial crisis, and exports are running at record levels; it should be noted that around 80 per cent of vehicles assembled in the UK are exported and more than half of these exports are destined for the European Union .

The SMMT – quite rightly I feel - highlights unrestricted access to the world’s largest single market, the negotiating strength of the EU to secure international trade deals, the ability to shape technical regulations and free movement of labour as being major factors in the UK auto industry’s recent success. I’d add in the ability to attract R&D funding in the industry from Europe.

Mike Hawes, SMMT Chief Executive, said: “We want this success to continue rather than jeopardise it by increasing costs, making our trading relationships uncertain and creating new barriers to our single biggest and most important market, Europe. Remaining will allow the UK to retain the influence on which the unique and successful UK automotive sector depends.”

Senior figures from a range of UK-based automotive echoed this message.

Rory Harvey, chairman of Vauxhall, said: "We are part of a fully integrated European company where we benefit from the free movement of goods and people. We believe not to be part of the EU would be undesirable for our business and the sector as a whole."

Tony Walker, Deputy Managing Director, Toyota Motor Manufacturing UK, said, “We believe that continued membership of the European Union is best for our business and for our competitiveness in the longer term.”

Below: JLR and UK car industry back Remain

And Dr Ian Robertson, Member of the Board of Management at BMW , said, “We firmly believe Britain would be better off if it remained an active and influential member of the EU, shaping European regulations which will continue to impact the UK whatever the decision on Thursday.”

Meanwhile, major auto makers took the step of writing to employees ahead of the referendum this week. While they all noted that it was up to workers themselves to decide how to vote, firms wanted to put over their point of view.

For example, in a joint letter to workers, the Chairman and MD of Ford of Britain, Andy Barratt and Nick Rothwell, CEO of Ford Credit Europe, stressed that: “Currently, Ford trades freely across the EU and with many other markets as part of existing EU trade agreements. The UK exiting the EU could mean such trade agreements would no longer apply to the UK, and result in a default to World Trade Organisation tariffs of up to 2.7 percent on our engine exports and import tariffs of up to 10 percent on incoming vehicles. This would significantly impact our business. The time taken to renegotiate trade agreements with the EU and other countries also risks leading to a prolonged period of uncertainty.”

Meanwhile, Nigel Stein, Chief Exec of components supplier GKN, and the GKN Executive Committee said in a letter to employees that “Leaving the EU would hurt our industries and GKN in the UK. Not straight away, but slowly, over time. The risks and uncertainties of a UK outside the EU will undermine investment and future jobs. When our customers come to decide where they want to build their next model of car or their next generation of plane, a Britain outside the EU will be a much less attractive location.”

And Jaguar Land Rover’s CEO Ralf Speth spelt out a simple message: “We at Jaguar Land Rover are convinced that we will be a stronger business – and a stronger country - if the UK remains a member of the European Union. Indeed, to leave would be highly damaging. If the UK was to leave the EU, it would become more difficult to buy components and sell our products in our largest market. Even the uncertainty caused whilst the Government tried to negotiate the UK’s exit and make new trade deals would be highly damaging. Remaining in the EU, I believe, will increase our chances to grow, create jobs and attract investment.”

Unite the Union also backed a ‘Remain’ vote. Unite’s general secretary Len McCluskey said:

“We have the most productive car industry in Europe because our workforce has been tireless in its efforts to make sure that UK built means world class. Leaving the EU puts all this hard work, all that graft, all the rights that protect workers and good businesses from cowboy employers, and our skills and investment in jeopardy.

Given the overwhelming voice of support for ‘Remain’ in the industry, it was perhaps unsurprising that the response from ‘Leave’ supporters was less than emphatic. Leave-supporting former British Chambers of Commerce DG John Longworth said on Radio 4’s Today programme: "The biggest power in the EU - Germany - exports way more cars to the UK than we do to them, so they are not going to allow the erection of tariffs because they would damage their own industry and shoot themselves in the foot. Even if, in a moment of madness, they did, what's the worst that can happen? German cars would become a little bit more expensive, we would buy a few less and would end up buying more British-produced cars."

Well, it could actually be worse than that Mr Longworth, in the auto industry at least. The ‘erection of tariffs’ could impact on trade, foreign direct investment and jobs in the UK auto industry. Leaving the EU would also end the UK’s ability to shape auto industry regulations in Europe.

* Professor David Bailey is writing in a personal capacity.