Pennzoil conventional oil in the yellow bottle is extremely cheap and easy to find in most major retailers. As one of the most popular conventional oils on the market, this oil is a safe bet. It has a strong additive package which is resistant to sludge, maintains performance, and also holds up well in used oil analysis reports. As with any conventional oil, it’s important to stick to regular oil changes every 3,000-5,000 miles. For the money, you can't go wrong with Pennzoil's Conventional oil.
Mobil 1 has for many years been one of the most popular synthetic oils on the market, but Mobil's non-synthetic Super also works very well. Mobil's popular "clean" oils have been replaced with Mobile Super, reflecting some changes to the formula and additives.
This oil claims to include more cleaning additives than others, with added friction-reducing additives as well. This is meant to extend engine life by protecting against wear and sludge. However, as with any conventional motor oil, it’s important to stick to regular interval oil changes of 3,000-5,000 miles.
Castrol is a very popular choice for synthetic oils, being well-known for their good quality overall. Castrol GTX, a conventional oil, rates well and was developed to resist sludge and protect your engine. Their additive blend includes Castrol's TriShield technology, which attracts and traps particles that cause damage, preventing sludge from building up. This oil holds up for intervals of 3,000-5,000 miles, and is capable of helping to improve fuel economy. Although Castrol GTX has a reputation for being somewhat overpriced, it depends on your region.
Quaker State Advanced Durability Motor Oil is a solid overall conventional oil that’s both affordable and easy to find at most major retailers. The naming scheme can be a bit confusing, with Advanced Durability being the conventional oil, Enhanced Durability being a blend, and Ultimate Durability being a full synthetic.
The Advanced Durability motor oil is good all-around, but focuses heavy on anti-wear, even exceeding wear standards. The additive blend prioritizes minimizing friction and preventing wear, even after heavy use. Be sure to change your oil every 3,000-5,000 miles, as with any conventional oil.