2018 Audi S4
Vehicle Specs & Maintenance Data
The 2018 Audi S4 maintenance specs on this page cover the key fluids, torque values, and wear items you need for routine service. Use these numbers as a quick reference when performing oil changes, tire rotations, brake jobs, and other scheduled maintenance on your Audi S4.
For oil changes, the 2018 Audi S4 takes 5W-40 Full Synthetic motor oil with a capacity of 6.9 quarts. Brake fluid type is DOT 4, the recommended coolant is G13 (Purple, phosphate-free), and transmission fluid is VW G 055 025 A2. Always use the manufacturer-recommended fluids to maintain warranty coverage and engine longevity.
When mounting wheels on the Audi S4, torque the lug nuts to 89 ft-lbs using a calibrated torque wrench. Over- or under-torquing can lead to warped brake rotors or loose wheels. Re-torque after 50 to 100 miles on newly installed wheels.
Owners of the 2018 Audi S4 have reported 5 common issues including "Timing Chain Tensioner Failure", "ZF 8-Speed Transmission Mechatronic Issues" and "Supercharger Nose Bearing Wear (3.0T)". Scroll down to the Diagnostics tab for detailed descriptions, solutions, and estimated repair costs.
Specifications on this page are compiled from multiple publicly available sources including manufacturer documentation, NHTSA data, and automotive databases. Always cross-reference with your owner's manual or official factory documentation before purchasing parts or performing any service.
The 2018 Audi S4 uses 5W-40 Full Synthetic motor oil (6.9 qt capacity), requires lug nuts torqued to 89 ft-lbs, takes DOT 4 brake fluid.
Manufacturer-recommended maintenance schedule for the 2018 Audi S4. Always verify intervals against your owner's manual.
Enter a diagnostic trouble code to see causes, symptoms, and fixes for the 2018 Audi S4.
Common problems reported by 2018 Audi S4 owners, with recommended fixes and estimated repair costs.
Timing Chain Tensioner Failure
The 3.0T supercharged V6 (older B8.5) or 3.0T turbocharged V6 (B9) can develop timing chain tensioner issues, leading to a rattling noise on cold start. If the tensioner fails completely, catastrophic engine damage can result from chain skip.
Replace the timing chain, tensioner, and guides. On supercharged 3.0T engines, the repair requires dropping the engine or removing the supercharger. Updated tensioner designs are available. Early detection via cold-start rattle is critical.
Est. Cost: $2,500 - $5,000ZF 8-Speed Transmission Mechatronic Issues
The ZF 8HP transmission (B9 S4) can develop mechatronic sleeve connector leaks and valve body issues, causing harsh shifting, delayed engagement, and shuddering during low-speed maneuvers.
Replace the mechatronic sleeve connector seals and perform a transmission adaptation reset. In severe cases, the valve body or complete mechatronic unit requires replacement. ZF transmission fluid service every 50,000 miles is recommended.
Est. Cost: $300 (sleeve repair) - $3,500 (valve body)Supercharger Nose Bearing Wear (3.0T)
On the B8.5 supercharged 3.0T, the supercharger nose bearing wears out, producing a whining or grinding noise that increases with engine speed. The bearing can fail completely, damaging the supercharger internally.
Replace the supercharger nose bearing or the complete supercharger assembly. Aftermarket upgraded bearing kits are available for a fraction of OEM supercharger cost. Some owners opt for a supercharger rebuild.
Est. Cost: $500 (bearing kit) - $4,000 (supercharger replacement)Carbon Buildup on Intake Valves
The direct-injected V6 engine accumulates carbon deposits on the intake valves, reducing airflow and causing rough idle, misfires, and reduced power output. Symptoms typically appear between 40,000 and 70,000 miles.
Walnut blasting or chemical cleaning of the intake valves. Install an oil catch can to reduce future buildup. Some owners perform this service every 30,000-40,000 miles as preventive maintenance.
Est. Cost: $500 - $1,000PCV Valve and Breather System Failure
The PCV valve and crankcase breather system develops failures causing excessive oil consumption, oil leaks from various seals, and check engine lights for lean conditions. The PCV diaphragm can rupture.
Replace the PCV valve assembly and inspect all crankcase breather hoses and connections. Updated PCV valve designs are available. This is a maintenance item that should be checked during regular service.
Est. Cost: $300 - $800