I've never been told by any tyre company to check my wheel nuts after X miles - not even kwikshit, who will deny responsibility for anything. However, there is a tyre-cum-breakers near Wareham (Trents) who display large signs with big red letters advising tyre customers to bring the vehicle back after 50 miles to have the wheelnuts checked. This puts the onus on them and not the customer for the safety of the vehicle - which is exactly where it should lie.
Ron.
My local tyre fitter of choice has always had the advisory on the invoice to check the tightness of the nuts/bolts after a few miles and most of the guys also verbally remind the customers as well. 
But I would challenge the legality of that as it is not reasonable, or practical, to expect a member of the public to do that, or remember to get a garage to check them, when, if the tyre fitter was doing his job properly and tightening the bolts correctly for long term use, then it should never be necessary, as, I would submit in legal argument, wheels do not regularly fall off when most motorists never carryout that re-tightening procedure. It is an unreasonable obligation being placed on the consumer as a "Get out Clause" to inhibit potential legal action against the tyre fitter if anything goes wrong. Motorists drive regularly 1,000's of miles between tyre changes, often on business, let alone domestic use, without re-checking those nuts, without any incident transpiring. That can be evidenced with the testimonies of millions of drivers, but can it be proved that the non-re-tightening of wheel nuts if done after 50 miles, or higher mileages, causes such a massive loss of a wheel, if the tyre fitter did his job correctly in the first instance? Can that actually be evidenced?
Just my thoughts, which may seem mad to some, but such practices by retailers and suppliers should be legally judged for their reasonableness, and questioned for their practical application, and not just an attempt to avoid legal action when they get it wrong. In other words nothing should not be questioned in law.
