Yesterday we told you about the Walmart customer who didn’t understand why his local Walmart refused to change the oil in his 2012 Fiat 500. He was simply told it was because the car wasn’t in “the book.” We asked if anyone could shine some light on this issue — and you responded.

J. has been working as a service tech at a Walmart Tire & Lube Express for about a year.

“I learned early on that Walmart is first and foremost always in “cover your arse” mode,” he writes, “particularly in the TLE department.”

That being said, J. points out that any good lube shop is very strict about what it will and won’t service in order to avoid liability issues later.

He calls out two issues that are essential to deciding whether or not the shop will perform the oil change.

The first is the drain plug — and whether or not the shop has the proper tool to handle that specific plug.

“Proper drain plug torque is absolute,” explains J. “If a drain plug is not the standard plug (i.e. a quick disconnect/self tapping or hand-removable plug) we are not, per policy, allowed to work on a vehicle, because we cannot properly torque a drain plug for which there is no torque wrench attachment of any kind, be it a socket or otherwise.”

Then there is the filter. He points out that Walmart, while a mammoth store, is not primarily an auto parts store, so it carries a limited range of oil filters. So even if the vehicle is in the book, Walmart might not have the proper filter in stock.

“If we do not have the filter for a vehicle, we do not do the service, period,” he tells Consumerist. “I will often try to call around to local parts stores to source a filter for customers, sometimes if things are not slammed, I will even go so far as to pick it up in my personal vehicle without issue — all in the name of service.”

Contributing to the problem, explains J., is that Walmart HQ expects TLE staffers to use FRAM oil filters, so the books his shop has only list FRAM products.

“We do not (and to my knowledge, nobody does) have a cross-reference book to find one and many filters may fit on a vehicle but are not the correct filter,” he writes. “This often leads to leaks later down the road if it doesn’t leak immediately during the post-service leak check.”

He asks a pretty sensible question: “Would you rather we work on your car with information on hand, or just wing it?”

Consumerist reader Richard is a former Walmart TLE staffer who agrees that it all comes down to liability.

“Walmart doesn’t want to be held liable for performing an operation that is not 100% by-the-book,” he explains, “and at the end of the day, what business does?”

However, Richard believes Walmart could be a little less hard-line about the policy, so long as the shop is clear about the risks in advance.

“I see no harm in the owner signing a waiver, allowing them to begin work/see what the filter is,” he writes. “But rather than go through all that mess, it is Walmart protocol to not even begin service on cars that aren’t ‘in the book.’ Love it or hate it, you can’t deny its efficiency and shifting of responsibility to the customer.”

Meanwhile, Sean, President of the SOCAL chapter of FIAT Club America, says he simply does not recommend going to Walmart to get your car serviced.

“They will not work on Mercedes and other high-end brands,” he tells Consumerist. “Their technicians are trained to perform only the most basic of services.”

But since even the simplest service can be screwed up — and since something like a messed-up tire change can have disastrous repercussions — Sean says Walmart won’t service many cars that are not among the most common you see on the roads.

He adds that, because of the Fiat 500’s Multiair engine, in which the valves are actuated through hydro-electronic technology, simply using the wrong weight of engine oil will change the valve timing.

This is not something I would want to put in the hands of a Walmart employee,” he explains. “If you go to Walmart and something goes wrong you deserve it.”

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