Why do 4S stores not recommend adding Shell gasoline?

[MacMorgan]

4S stores do not recommend adding Shell gasoline to prevent new cars from experiencing fuel-related failures. In fact, the issue with Shell lies in its additives. Excessive additive dosage can lead to low heat value, loud noise, and poor performance in cars. In China, Shell Petroleum, like most joint ventures, closely collaborates with Yanchang Petroleum and Sinopec. Shell is primarily responsible for sales and management; however, the supply channels for gasoline and diesel are from domestic refineries. This means that Shell gasoline in China is most likely supplied by Sinopec's refineries. Gasoline is a volatile, flammable hydrocarbon mixture liquid obtained through fractional distillation, cracking, or pyrolysis of petroleum and can be used as fuel.

[Kristin]

The technicians at the 4S shop told me they don't recommend Shell mainly due to oil formulation issues. You see, the additive compositions vary significantly between different gasoline brands. Shell's signature cleaning formula might not align with certain engines' original factory designs. Our workshop has tested many cases where long-term use of such third-party oils tends to cause injector carbon buildup or sensor false fault codes. Besides, their service department dreads disputes when handling maintenance orders. If you use Shell and encounter engine problems, it's impossible to determine whether it's the oil's fault or the vehicle's issue. It's much simpler to just push the partnered gas station's oil.

[McHarley]

I heard about this from a 4S store salesperson in a car owners' group before. To put it bluntly, it's all about profit-sharing agreements. They have long-term contracts with state-owned gas stations like the two major oil companies (Sinopec and PetroChina), and they get commission rebates for recommending car owners to refuel there. If everyone goes to Shell stations instead, this shared income would disappear. However, the salesperson also admitted that gas station supply channels are complicated nowadays, and some small franchise Shell stations indeed have unstable fuel quality. Once, I refueled at a Shell station in the suburbs and the engine light came on. When I went back to the 4S store, I was charged 500 yuan for diagnostics. The key is to choose reputable gas stations and not to go for cheap fuel at small stations.

[AubreyLynn]

A car engineer friend once explained this phenomenon to me: the core issue lies in the fuel certification system. The maintenance manuals provided by automakers to 4S dealerships clearly specify the use of gasoline that meets the GB17930 certification standard, and Sinopec and PetroChina's fuel tankers come with traceable codes upon delivery. However, as a foreign brand, Shell's blended fuels may sometimes contain lower-grade components, resulting in significant fluctuations in octane levels. As someone who drives a German car, I've experienced this firsthand. Last year, I tried Shell for three months and noticed significantly slower cold starts, but everything smoothed out when I switched back to the manufacturer-recommended 95-octane fuel. It's not that Shell is bad, but 4S dealerships have stricter quality control over fuel because repairing precision direct-injection engines is simply too expensive.

[CarterRose]

A relative who used to work in gas station management revealed some inside knowledge about fuel quality. An important reason why 4S stores resist Shell is logistics chain monitoring—their partnered gas stations maintain temperature control from the refinery all the way to the fuel nozzle, but third-party fuel might be adulterated during transportation. Last month in our city, a Shell transport vehicle was caught blending 92-octane fuel into 95-octane. Statistics from 4S stores show that the complaint rate for engine failures is 20% higher among car owners who use non-recommended fuel. Mechanics have to remove spark plugs to check for carbon deposits, doubling the labor cost. If you really want to use Shell, it's recommended to go to direct-operated stations like those on highways, and avoid small stations near local refineries.

[ElianaFitz]

The mechanic privately told me: Actually, many 4S shops don't recommend Shell because they've been burned before. Two years ago, a batch of Japanese cars collectively threw fault codes, and the investigation finally revealed that those owners had all refueled at the same Shell station. The excessive manganese additive in the fuel damaged the oxygen sensors. The manufacturer refused to cover the damages, and the 4S shop had to foot the 200,000 yuan repair bill. Now they've learned their lesson and directly print a list of recommended gas stations to hand to customers. However, Old Master Li mentioned that Shell has upgraded its formula now, and he's been using it in his American car for over three years without issues. It really depends on the car model—German cars with particulate filters are better off not taking the risk.