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.