Kendall GT-1 Max vs Valvoline VR1

These engine oils are totally synthetic, utilized in only gasoline engines. The main focus of Kendall GT-1 Max is on fuel economy while Valvoline VR1 generally emphasizes on engine rinsing and anti-wear protection.

 Due to the lower formation of ZDDP ash in GT-1, it is more amiable towards the performance of the catalytic converter. It also protects the pre-ignition of the oil. High concentration of calcium-based detergents also provides compatible protection against sludge formation. Its performance at higher temperatures is quite dominant with less variation in its viscosity. Same goes for colder temperature as well. It also provides longer oil change intervals thus providing higher fuel economy.

VR1 provides excellent cleaning against sludge and deposits formation due to its higher concentrations of calcium along with magnesium detergents. It also provides more resistance against the issue of foaming production. A large amount of anti-wearing agents in this oil provides extra protection against the problem of wearing and tearing of the engine. It shows good performance in cold conditions.

DescriptionKendall GT-1 MaxValvoline VR1 (10W-30)
Category of oilEntirely syntheticEntirely Synthetic
Engine CategorizationOnly GasolineOnly Gasoline
Viscosity grades availability5W-30, 0W-16, 5W-20, 0W-20, 10W-3010W-30, 20W-50, SAE 30, 40, 50, 60
Cost (1 Quart.)6.67 $5.48 $
Duration of oil interchange (miles)10,000-15,0003000-4000
AdditivesDispersants, Foaming resistant, DetergentsAnti-foaming reagents, Wearing-resistant, Friction Modifiers

Comparing prior oil combustion

The availability of lighter-weight molecules decides the early burn-off of the oil. As the temperature rises, these lower-weight molecules will break down quite easily and quickly vaporize. The flashpoint of the oil must be high to provide better oil burn-off protection.

VR1 has a relatively lower flashpoint therefore, it vaporizes sooner. Conversely, the higher flashpoint of GT-1 allows better stability and better protection against the pre-burning of the oil. So, it has lower volatility and is more competitive in this regard.

Comparing oils (Oils Grade 10W-30)Flash-point (Centigrade)
Kendall GT-1 Max232
Valvoline VR1210

Comparing Protection against Engine wear

Anti-wearing additives are being put in the oil to lower the problem of the wearing of an engine. These wear resistive agents form a slightly thin layer around the metal parts which restricts them to slide over one another. This method reduces the friction between these moving components. A greater addition of these additives will prove to be more beneficial in serving this cause.

Zinc, as well as, phosphorus-based anti-wearing additives are the main constituents in both these oils whereas VR1 contains higher quantities of these compounds. GT-1 contains a faintly higher concentration of boron while molybdenum is present in a relatively larger amount in VR1. Some traces of titanium are also found in VR1.

Comparing Oils (Oils Grade 10W-30)Amounts of Zinc compound (ppm)Amounts of Phosphorus compound (ppm)Amounts of Boron compound (ppm)Amounts of Molybdenum compound (ppm)Amounts of Titanium compounds (ppm)
Kendall GT-1 Max697508206300
Valvoline VR110809412056632

Viscosity Comparison

Greater kinematic viscosity will enable the oil to perform well at higher temperatures. Viscosity index is known as the dissimilarity in the oil’s original viscosity with temperature change. This viscosity index is needed to be high in order to maintain the viscosity at higher temperatures. Pour point is a minimum temperature below which the fluid loses its flowing characteristic.

The kinematic viscosity of GT-1 at both medium (40 Celsius) and higher temperatures (100 Celsius) is greater compared to its peer. VR1 has a comparatively lower viscosity index which allows more changes in its viscosity at higher temperatures. GT-1 also has a very commendable performance in cold temperature conditions because of its lower pour point.

Comparing Oils (Oils grade 10W-30)Normal Temperature (40 o C) kinematic viscosity (cSt)Higher Temperature (100 o C) kinematic viscosity (cSt)Index of Viscosity Pour-point (Centigrade)
Kendall GT-1 Max69.711.8166-39
Valvoline VR16810.7146-33

Contrasting Effectiveness of catalytic converter

Anti-wearing compounds consisting of zinc plus phosphorus elements, convert into ash as a result of oil burn-off. This ash launches into the catalytic converter making it poisoned. As a result, the poisoned converter won’t be able to function properly.

GT1 contains a relatively lower amount of zinc along with phosphorus compounds. Contrarily, VR1 has both these compounds in abundance. Therefore, the formation of ash will be more in VR1. This leads GT-1 to provide better functioning of catalytic converter comparatively.

Comparing oils (Oils grade 10W-30 Grade)Amounts of Zinc (ppm)Amounts of Phosphorus (ppm)
Kendall GT-1 Max697508
Valvoline VR11080941

Comparing oil sludge production

The enriched oxygen oil combines with dirt or some other debris to form a thick black liquid known as sludge. This sludge inhibits the engine to function properly. To overcome this problem of sludge formation, some cleaning agents’ detergents along with dispersants are incorporated into the oil.

GT-1 mainly consists of calcium-based detergents to minimize the production of sludge. Magnesium-based compounds are available in very low quantities. Small traces of an anti-foaming reagent (silicon) are also present in GT-1.

VR1 contains a greater number of detergents made up of calcium plus magnesium. It contains a small quantity of sodium-based detergents as well. Silicon is also present in good numbers providing better resistance against foam build-up. Overall, its performance is more dominant in cleaning away the sludge.

Comparing oils (Oils Grade 10W-30)Amounts of Sodium (ppm)Amounts of Magnesium (ppm)Amounts of Calcium (ppm)Amounts of Silicon (ppm)
Kendall GT-1 Max0515222
Valvoline VR1287011869

Comparing the Oil interchanging interval

The oil changing frequency of GT-1 is lower compared to its rival. The oil is needed to be changed after an interval between 10,000 to 15,000 thereby, providing a longer span of oil exchange. On the other hand, the span of exchanging VR1 is short and the oil is required to be replaced after the duration of every 3,000 to 4,000 miles.


  • These are completely synthetic engine oils used in gasoline engines.
  • GT-1 provides better catalytic converter protection due to its low ZDDP.
  • VR1 provides better resistance against sludge build-up as it contains higher detergent concentrations.
  • Anti-foaming agent is present in higher numbers in VR1 to provide better protection against foaming.
  • GT-1 protection against early oil burn-off is better due to its greater point ignition.
  • VR1 contains a greater amount of wear resistive reagents providing superior shielding from engine wearing.
  •  GT-1 has a higher kinematic viscosity at both 40 o C and 100 o C so its performance is comparatively better at these temperatures.
  • At lower temperatures, GT-1’s performance is again more dominant.
  • The frequency of changing the oil is greater for VR-1 compared to its counterpart.
  • GT-1 is more expensive than its counterpart.