Customer Supplied Parts
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Customer Supplied Parts

Neil Pattemore explains why garages should think twice before agreeing to fit a part supplied by the customer.

In the modern age, it is increasingly normal to search for products and services at the best price, often via the internet. However, when this relates to drivers buying parts and then bringing them to your workshop to fit, there are legal, moral and commercial dilemmas.

To look at this in more detail, let’s start with the legal aspect. I am not a lawyer, but my understanding is that as soon as you agree to fit parts supplied by your customer, you accept the liability that is directly associated with the fitting, function, warranty or guarantee implications that come with it. You are considered to be an ‘expert’ who relies on their professional status to reasonably judge that the part provided is fit for purpose. This is especially an issue if that part is a component sourced as a second-hand part.

Yet, even if the part is new, it may be difficult to ensure that it is the correct part and that it can be correctly fitted and subsequently function correctly. Any issues and you are immediately into an argument with the customer, especially if the part subsequently fails. There is a legal obligation for the parts manufacturer to provide a warranty, but there may also be a guarantee, which is entirely optional and is often used as a marketing tool. This may include the cost of the labour to replace a faulty part. In the event of the part requiring replacement, who becomes physically and financially responsible to return, replace and fit the replacement part, especially if the seller is a well-known ‘on-line marketplace’? Good luck with that then.

It is also illegal for the vendor (in this case, you) to impose any conditions about the parts manufacturer’s warranty, so (for example) you cannot remove any responsibility from the work that you have provided, or impose restrictive conditions, such as ‘no warranty’. The key issue often then comes down to being able to clarify the ‘burden of proof’.


There is a moral responsibility, as you also have a ‘duty of care’, concerning the services you provide and that the customer’s vehicle remains safe, secure and compliant once the work is completed. This may be possible with the parts supplied by the customer, but it introduces a significant unknown risk, that in particularly serious cases could even mean the end of your business and the livelihood of both you and your staff.

From the commercial aspect, it is a much more fundamental position. You are in business to make a profit and this is typically generated by selling both your workshop time, and the various parts and components that should generate a healthy margin and be an important part of your profit. If you don’t provide the part, then you can only sell time and as your fixed costs will not have changed, then to remain profitable, you must increase your hourly rate. This is highly unlikely to be an attractive proposition to the sort of customer who wants to ‘save a few quid’ by buying their own parts. Quite simply, why would you want to be a busy fool?

Equally, if a part needs to be fitted by a professional, then it should be an integral part of the package of expertise, recommendation and parts that fulfil the required work. I could also argue that if a part is cheap, then the buyer should beware; there is probably a good reason!

It could also be argued that at the end of the day, you can’t turn down work in this day and age. But maybe that is the point – in this day and age, it is exactly why you should be turning down this type of work. Customers are often unaware of what they are really asking when they want you to fit parts that they have sourced and you become liable when it all goes wrong. Perhaps the only exception is if a customer wants you to fit a simple part like a second-hand glovebox, or it is an old car where new spares are no longer available. Then it may be an exception.

Ultimately, this comes back to what has been said before – it’s not about turning the customer away, but instead it is about educating the customer about your involvement in the complete process of sourcing, fitting and support. This has an intrinsic value and can create a win-win situation when helping to find the best solution for the customer. If they don’t buy-in to your offer, then it should be a ‘Goodbye!’ from you to the customer – the potential reward does not warrant the risk. There are no winners in a race to the bottom.

Looking further ahead, this question of fitting parts from different sources will take on a whole new perspective when 3D printed parts become more common, especially if they require a corresponding type approval documentation trail. I will leave you to ponder how you might react then!

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