oil temperature VOLKSWAGEN JETTA GLI 2013 1B / 6.G Owners Manual

Engine oil quality is based not only on requirements for engines and exhaust treatment systems, but also on fuel quality. Engine oil comes into contact with fuel and fuel residue in all internal combustion engines, causing engine oil to age and its lubricating qualities to deteriorate.
Your engine was factory-filled with a high-quality, “synthetic” all-season engine oil that meets strict Volkswagen oil quality standards and has a viscosity grade of SAE 5W-40. or SAE 5W-30. You can use this oil for normal driving in all temperatures.
If you need to add oil between oil changes, use only a high quality oil that expressly complies with the Volkswagen oil quality standard specified for your vehicle's engine:

Engines Engine oil specification
Gasoline engines VW 502 00 VW 503 00 VW 504 00
At the time this Manual was printed, the engine oils available in the U.S. that meet these Volkswagen standards are “synthetic” oils. This does not mean, however, that any “synthetic” engine oil will meet Volkswagen standards. Always use an approved oil that expressly complies with the Volkswagen oil quality standard that applies to your vehicle's engine.
General recommendations:
If “synthetic” oil that meets the applicable Volkswagen oil quality standard with viscosity grade SAE 5W-40 or SAE 5W-30 is not available in your area, be sure to use a viscosity grade suitable for the climate, season, and operating conditions that exist where the vehicle is used. Make sure the oil meets the quality standard
Engine oils are constantly being improved. Authorized Volkswagen dealers and authorized Volkswagen Service Facilities are always up-to-date regarding new developments and changes. Volkswagen therefore recommends that you have the engine oil changed by an authorized Volkswagen dealer or an authorized Volkswagen Service Facility.
NOTICE
x If you need to add oil and there is none available that meets the Volkswagen oil quality standard your engine requires, you may add a total of no more than 1/2 quart (0.5 liter) of a high-quality “synthetic” oil that meets ACEA A3 specifications and has a viscosity grade of SAE 5W-40 or SAE 5W-30.
x Use only a high quality engine oil that expressly complies with the Volkswagen oil quality standard specified for your vehicle's engine. Using any other oil can cause serious engine damage that will not be covered by any Volkswagen Limited Warranty.
x Do not mix any lubricants or other additives into the engine oil. Doing so can cause engine damage! Damage caused by these kinds of additives are not covered by any Volkswagen Limited Warranty.
Engine oil capacities