Top 10 Best Oil For High Mileage Chevy 350 In 2023

Oils are the blood of a vehicle’s engine. 

Choosing the best oil for high mileage chevy 350  is absolutely necessary from many angles. It does not just increase the durability & lifespan of your vehicle, but boosts the overall performance.  

As there are a lot of variable options available in the market, it is tough to choose the best one. Luckily I have done that hard part of the job for you.  

Here, I will talk about the top 10 high mileage Chevy 350 oils for your favorite vehicle. Starting from their in-depth comparison to different pros & cons, you will get all the information you need to choose the perfect one. LET’s go!

In A Hurry? Here Is Our Quick Comparison.

NameOil TypeViscositySize Price
1. Castrol 03111-3PK GTX High Mileage 10W-40 Motor OilSynthetic Blend10w-405 QuartsVery High
2. AmazonBasics Full Synthetic 0W-40 Motor OilFull Synthetic0w-405 QuartsHigh
3. Mobil 1 High Mileage Full Synthetic Motor Oil 0W-20Full Synthetic0w-205 QuartsHigh
4. Pennzoil High Mileage Conventional 10W-40 Motor OilConventional oil10w-405 QuartsHigh
5. Valvoline High Mileage with MaxLife Technology SAE 5W-30 Synthetic Blend Motor OilSynthetic Blend5w-305 QuartsMedium
6. AmazonBasics High Mileage Motor Oil – Synthetic Blend – 5W-20Synthetic Blend5w-205 QuartsLow
7. Valvoline High Mileage with MaxLife Technology SAE 10W-40 Synthetic Blend Motor OilSynthetic Blend10w-405 QuartsLow
8. Pennzoil High Mileage Synthetic Blend 5W-30 Motor OilSynthetic Blend5w-301 QuartHigh
9. SeaFoam High Mileage Motor Treatment HM16Oil additiveX16 ozVery Low
10. Lucas High Mileage Oil StabilizerOil additiveX32 fluid ouncesVery Low

Top 10 Best Oil For High Mileage Chevy 350

1. Castrol 03111-3PK GTX High Mileage 10W-40 Motor Oil

My first pick is the Castrol high-mileage 10-W 40 oil. Coming from one of the most famous brands, this oil has less phosphorus & prevents the engines from system failure. 

There are many reasons why I use this particular oil so often.

As it has seal conditioners, my engine is protected from getting any kind of leakage inside the engine. Also, the engine is properly lubricated because of good dispersant function.

It comes in different packs which meets with the chevy 350 oil capacity. It comes comparatively with a cheap price as well. It has synthetic blend & it’s specially designed for engines over 75,000 miles.

Protecting the engine from any sludge & avoiding oil burn-off makes it even greater.  Providing all of these benefits, this oil also has approval from ILSAC GF-5, API SN.

  • Prevents deposit build up.
  • Provides Oil burn-off protection.
  • Gives protection against leakage & sludge.
  • Excellent dispersal system & has extra additives.
  • Prevents system & catalytic converter failure.
  • It is not fully synthetic.


This is undoubtedly one of the best oils you will get in the market. I use it regularly & trust me it hasn’t disappointed me. It will definitely increase the overall performance & help you to keep proper maintenance.

2. AmazonBasics Full Synthetic 0W-40 Motor Oil

AmazonBasics has made this oil specially for different kinds of Turbo-charged vehicles. But it can definitely be used in other chevy 350 vehicles.

It is a fully synthetic oil. This chevy 350 oil has very high resistance to thermal breakdown. It helps to get less engine wear by reducing the friction. Improves the power production in the engine as well.

This full-synthetic chevy 350 oil helps to lubricate & provides protection on the other parts of the engine. It increases the overall fuel-efficiency & improves the life-span.

This AmazonBasics oil prevents the engine from rust & corrosion by preventing any kind of harmful build ups. 

This oil is also built in a way that it is formulated for any kind of long drain intervals. It also reduces any kind of exhaust emissions by resisting viscosity and preventing undesirable burn-off.

  • Really good for european models, turbo charged vehicles.
  • Low price
  • Has good capability of handling high heat.
  • Reduces friction & exhaust pollutants.
  • There is no clear visibility strip on the bottle.


It comes at a low cost & does the job. If you are using a turbo-charged vehicle, then this definitely should be your choice. For vehicle maintenance & changing oil it does a pretty top-notch job.

3. Mobil 1 High Mileage Full Synthetic Motor Oil 0W-20

Honestly speaking, no one can make a top list of oils without mentioning this Mobil 1 motor oil.

It is fully synthetic like the previous one. This fully synthetic oil meets the ILSAC GF-6 standard. So it helps in the LSPI issue & keeps the engine clean.

It is specially designed for engines over 75000 miles and has a proprietary blend that protects 10000 miles between oil changes.

For any high mileage chevy 350, this oil contains a seal conditioner & prevents any kind of oil leakage. Reducing friction, prevention of deposits & sludge build up everything is met by this special oil.

It is technologically built in a way that it provides low-temperature protection upto -40 degrees Fahrenheit and internal engine heat protection up to 500 degrees Fahrenheit. 

Impressed already? That’s not just it. This oil is made in such a way that it protects from five factors that can damage engines over time.

  • Helps to extend engine life.
  • Protects the engine from five damaging engine factors.
  • Provides exceptional temperature protection.
  • Improves the overall fuel economy.
  • Gives sufficient engine wear protection.
  • Outstanding oxidation resistance.
  • The container has leakage problems according to some of the users.


This oil has a lot of offerings under this budget. It has many key features which goes perfectly for our high mileage chevy 350s. So you can use it for both new & the old ones.

4. Pennzoil High Mileage Conventional 10W-40 Motor Oil

Your car has accumulated more than 75000 miles? Faces different oil leaks & oil burnt off problems? Then this oil will do its job for you.

Pennzoil introduced this oil with an excellent combination of different additives & special conditioning seal agents. It helps to prevent leakage problems for old engines. 

It is also recommended for vehicles over 75000 miles. It is formulated & designed for new or late model SUVs, different passenger cars, light vans and trucks.

It has an excellent combination of different materials which helps this oil to remove sludge, keep dirt & pollutants out. 

It increases the efficiency of the engine & you can cover good distances easily. It keeps the internal parts of your engine clean. The advanced formula used in this engine also keeps the other components of the engine very clean.

  • Really good for old & dry engines.
  • Prevents leakage problems & removes sludge.
  • Has protection from harmful deposits.
  • Anti-wear protection is ensured.
  • Keeps the components of the engine clean.
  • The bottles don’t come up with the best caps.


The combination of special conditioning seal agents and different additives takes this oil to the list of best oil for high mileage Chevy 350. If your engine is relatively old & you want to get the best outcome from it, you can go for this one.

5. Valvoline High Mileage with MaxLife Technology SAE 5W-30 Synthetic Blend Motor Oil

This synthetic blend motor oil is one of the most famous & reliable oils out there in the market.

It is developed with Maxlife Technology and easily boosts up the engines overall performance. It is stated that this oil offers 40% better wear protection. And it keeps the other components of the engine in a good condition.

The advanced formulation of this oil helps our engines to maintain the horsepower. Built with different anti-corrosion additives & detergents, it helps in reducing sludge, leakage & rust.

This synthetic blend motor oil gives its best performance under any kind of temperature. The anti-oxidants resist motor oil breakdown in any kind of driving condition.

Moreover, it provides good safety to engines with over 75000 miles.

  • Good temperature protection.
  • Reduces sludge, corrosion & rust.
  • Properly lubricates the moving parts.
  • Maintains good wear protection & horsepower in the engine.
  • There isn’t anything that I personally disliked in this budget.


It is definitely one of the most technologically advanced oils out there. In short, I personally use this too & recommend you to use it as well. You will get good performance from your engine & it will also help to get good lifespan.

6. AmazonBasics High Mileage Motor Oil – Synthetic Blend – 5W-20

It is time for another AmazonBasics product. 

This AmazonBasics high mileage oil is good for vehicles with longer drain intervals. It is one of the best for budget customers. It comes just for less than 20 bucks.

This chevy 350 oil provides good protection for engines over 75000 miles. When I used it a couple of times I got to know a lot of things. It comes with better thickness than most other oils.

The seal conditioner in it helps to prevent leakage problems. The materials used in it helps it to reduce LSPI & provide good protection for high mileage vehicles. 

It has high resistance to viscosity & reduces any kind of thermal breakdown.  This high-mileage synthetic blend oil helps to decrease exhaust emissions. Also minimizes engine deposits.

  • Budget-worthy.
  • Prevents thermal breakdown.
  • Minimizes the low speed pre-ignition.
  • Minimizes engine deposits.
  • Reduces exhaust emissions.
  • The cap & body of the bottle could be better.


Under this budget, this oil is definitely a good choice. If you want good maintenance under a small budget, then you can undoubtedly use this one.

7. Valvoline High Mileage with MaxLife Technology SAE 10W-40 Synthetic Blend Motor Oil

I’ll talk about another Valvoline High mileage oil, but this one’s viscosity is 10W-40. It is suitable for older models. 

It has the MaxLife technology which automatically makes it better than many other oils. 

What does the MaxLife technology do? It simply maximizes the lifespan of your engines. Keeps them in very good shape. 

Just like the other one it provides good wear protection & temperature protection. It properly lubricates moving parts. This technologically advanced oil helps to maximize the engine’s power.

The Valvoline 10w-40 synthetic blend motor oil uses seal conditioner to avoid the leakage problems. 

Different kinds of detergents & additives are used to reduce sludge, deposit formation, rust & corrosion. No wonder why it is everyone’s favorite!

  • Technologically advanced.
  • Good temperature protection.
  • Reduces sludge, deposit formation, rust & corrosion.
  • Provides good lifespan & maintains good horsepower.
  • There isn’t anything that I personally disliked in this budget.


Just like number five, I only have good things to say about this one. In this technologically advanced oil, you will get everything you need to keep your old engine in safe hands.

8. Pennzoil High Mileage Synthetic Blend 5W-30 Motor Oil

The Pennzoil High Mileage Synthetic Blend 5W-30 Motor Oil is undoubtedly one of the best oils for high mileage chevy 350 out there. 

The 5W-30 is actually used for newer models. So if your choice is from the Pennzoil brand & you use models like L83 or L 98. Then this is what you should go for. 

The company recommends it for engines with over 75000 miles. It provides good protection for the engine parts.

Reduces leaks & oil consumption by its different seal conditioning agents. This Pennzoil high mileage oil meets the requirements of API SP.

Not only does it prevent oil leakage, but also the good formulation helps in overall lubrication, prevents sludge & reduces harmful deposits. It also keeps the high power engine clean.

  • Good for new models.
  • Ensures proper safety of the engine.
  • Prevents sludge, leakage & engine breakdown.
  • Some people didn’t like the packaging.


This specially formulated oil uses different special agents to reduce leakage problems, sludge & other damaging deposits. I used it once in my LT-9 & it was satisfactory. You can use it for lifespan & overall increased performance.

9. SeaFoam High Mileage Motor Treatment HM16

Here I’ll talk about an additive, which will definitely help you to get the performance from your high mileage Chevy 350.

The Seafoam High mileage motor treatment helps in cleaning & lubricating properly. It won’t cost you that much but will definitely increase the durability of your favorite car.

It also helps to prevent oil burn and reduce the long-term engine wear.

This HM16 is really easy & simple to use. It is specially formulated in such a way that if you use it in a proper way, you won’t experience any rough engine performance.

  • Helps in increasing the durability.
  • Low cost.
  • Helps the engine to run noth longer & faster.
  • Reduces long-term engine wear.
  • Lubricates the critical engine areas.
  • The design of the bottle could be better.


I have been using this product for a couple of years now. And trust me when I say this, it has increased my engine’s performance. So try it out, I believe you won’t be disappointed.

10. Lucas High Mileage Oil Stabilizer

The last product I’ll suggest is the Lucas High mileage oil stabilizer. This additive is made of different premium base oils & petroleum extractives. 

It has been tested & it offers great reliability. You can get maximum lubricity by using this product. But keep in mind that the ratio has to be 1:4 between this lucas oil stabilizer & original oil. 

This oil stabilizer helps to raise the oil pressure, which helps to get better overall performance from the engine. 

Here’s the best thing! I have an amazing experience regarding this product. I tried multiple products to solve the oil burn issue in my chevy 350 vehicle. There wasn’t any significant improvement.

But when I used this one, the oil burn went to 1qt per 1200 miles from 1qt per 400 miles. 

This additive is much slicker than original oil & helps to reduce things like friction, heat etc. It also eliminates dry starts( creates most damage & wear), leaks & overheating issues.

  • Helps in oil burn issues.
  • Ensures maximum lubricity.
  • Raises oil pressure.
  • Eliminates dry starts & leakage problems.
  • Increases efficiency & reliability.
  • Comes at a cheap price.
  • It’s hard to maintain the ratio sometimes.


You have heard my experience with this product already. So I highly recommend using it for high mileage vehicles, different recreational cars & military vehicles as well.

Things To Consider When Buying Best Oil For High Mileage Chevy 350 [Buying Guide]

I guess now you know each & everything about these top 10 high mileage chevy 350 oils. But before actually buying your desired oil, here’s a guide you should follow first:

Overview of Chevy 350

You probably know a lot of stuff already, but here’s a quick summary!

Chevy 350 is a small block v-8 engine. It is made by Chevrolet. There’s a reason why it is called a small block engine.

Although it is the same basic engine block as other Chevy cars, it is comparatively smaller. Just from 4.3L to 6.6L engines or 262 cubic inches to 400 cubic inches. It is mainly a series of V8 automobile engines. 

Chevy 350’s first appearance was back in 1967. Although it is relatively smaller from the other engines, it only has a few key differences from them.

Types of Oil

As there are a lot of oils available in the market, you should get a brief idea about their types. They can be identified mainly into three categories.

  1. Synthetic Blend: It is also known as mixed oil. It is mainly a mixture between different minerals & additives. This type of oils help to reduce the cost.

It increases the efficiency, provides protection, and improves other performances of the engine.

  1. Mineral Oil: Another type of oil is the mineral oil. But the use of these oils is decreasing day by day. Because of having lackings in molecule variations, it couldn’t keep up with synthetic blend oils & full synthetic oils.
  1. Full Synthetic: What is full synthetic oil? The oils which have 100% synthetic molecules. My personal experience tells me, these are the best type of oils out there and you should definitely use them.

Expense? Yes they can cost you a bit of money. But hey, we are talking about your car man! These oils help to keep a good lifespan. They work in all kinds of temperatures & enhances the protection.

These oils are clearly better than the other two. 

Size of the Canister 

A lot of people forget about this. But you must always think about the size of the bottle. 

If you’re short of oil after buying a can, then you have to buy another one & end up paying extra money. So know exactly how much oil you need.

Five-quart containers are the most used ones. And luckily the Chevy 350 holds exactly 5 quart as well. It is similar to around 4.7 liters. So buy exactly the amount you need.


There are new products which are creating a name for themselves in the market. But famous oil brands have kept a strong position & they provide good after sales service as well. 

Here are the top 3 brands which offer the best oil for high mileage Chevy 350.

  1. Castrol
  2. Valvoline
  3. Mobil 1

But again, don’t just go for brands based on their names. Check the reviews, see if they are personally good for you and then go for them.


Viscosity actually means thickness. It is the flow speed of the oil. Depending on the weather, the speed of the oil varies.

Let me break it down to you. In the viscosity level, the number stands for the level & ‘W’ stands for winter. For example, 5W-20 says that viscosity grade is 5 during winter. And when it is a hot environment, the viscosity is 20. 

So definitely you should go for a low viscosity level in winter. Check the owner’s manual to know which level will exactly be perfect for your Chevy 350. As for a hot environment, stay from 30 to 40.

Frequently Asked Questions [FAQ]

1. What oil is best for a Chevy 350?

Answer: Full synthetic oils are undoubtedly the best choice. But you can also use the synthetic blend too.

For latest models, the 5W-30 is considered the best. So if you are using Chevy 350’s like the L83, L98 or LT-9 then go for the 5W-30. It will also meet the Chevy 350 oil capacity.

However, if you are using relatively older models, then go for 10W30 or 10W40. So if you have cars like a L82 like me, use these oils.

2. How many quarts does a Chevy 350 take?

Answer: Most of the Chevy 350s take 5 quarts of oil. But there are very few ones that can hold upto 6 quarts. So if you are using a common unmodified model, it is likely that the oil capacity in the Chevy 350 will be 5 quarts.

3. How much oil does a Chevy 1500 take?

Answer: Well it depends on the model & other components.

The Silverado 1500 6.2L 8-cyl Engine takes around 8 quarts which is around 7.6 liters. On the other hand the Silverado 1500 4.3L 6-cyl Engine & Silverado 1500 3.0L 6-cyl Engine takes around 6 (5.7 liters) & 7 quarts (6.6 liters) respectively.

4. What size is the oil drain plug on a 350 Chevy?

Answer: Although it can differ sometimes but the threads are usually 1/2″-20. While the requirement of a stock drain plug is 9/16″ wrench. It is so that the hex head fits perfectly

5. Is 5W30 Better Than 10W40 Oil?

Answer: Well it depends on the environment in which you are using your vehicle.

If you live in a hot & warm environment then 10W40 will be the better option. But if you have to use your vehicle in winter, then 5W30 is better than 10W40.

Final Thought

To conclude,I think everything stated above will help you to get the best oil for high mileage Chevy 350.

I used my personal experience & intense research to get these top 10 products. I assure you these are the most reliable, durable & best oils out there. 

Although I always go for Castrol & Valvoline, you should go for your personal choice. Check the reviews, see the price, get an idea about the features. Keep everything in mind & choose the personal best one for you.

I hope you will get the best one. It will definitely boost the performance of your engine & increase the overall lifespan. 

Till then, Drive Safe!

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