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Can I Use Transmission Fluid in Oil to Clean My Engine?

Can I Use Transmission Fluid in Oil to Clean My Engine?

Yeah – those youtube rescue channels all show using ATF to clean out the engine – they’re doing it the hard way…

ATF is not made to clean sludge from engines. Instead, it’s best to use a dedicated engine flush.

AMSOIL Engine & Transmission Flush helps to remove sludge and deposits from engines and transmissions.

_by Phil Collinsburger |May 5, 2022

Over time, engines can accumulate deposits that reduce power and performance. Since automatic transmission fluid contains detergents to clean sludge, some DIYers add a small amount of transmission fluid in their oil to clean the engine prior to oil changes.

ATF, however, is not formulated for use in automotive engines. Instead, a product that’s designed to flush engines is a far-superior approach.

How Sludge Forms

Stop-and-go driving, prolonged idling, trips too short for the engine to reach full operating temperature, towing, the ingestion of airborne dirt, fuel dilution, water condensation and oxidized oil all can promote sludge build-up in motor oil and transmission fluid.

Sludge clogs narrow oil passages, restricting oil flow to vital parts, especially the upper valve train area, causing wear.

Transmission Fluid In Oil Reduces Cleaning Power

In most cases, adding automatic transmission fluid to motor oil reduces cleaning power. That’s because the detergency of ATF is less than motor oil. Why is that?

ATF is exposed to lower levels of combustion byproducts and contaminants than motor oil, so it is formulated with reduced detergency. Instead, ATFs have elevated levels of friction modifiers and other additives that help protect gears and clutches.

Transmission Fluid In Oil Reduces Wear Protection

Second, adding ATF alters the motor oil formulation and reduces its effectiveness.

A good motor oil is a fine balance of base oils and additives designed to fight wear, reduce friction, prevent deposits and slowly dissolve accumulated sludge. The cleaning power of motor oil is designed to work gradually over subsequent oil changes and not necessarily all at once. Adding a foreign substance to the oil disrupts the formulated chemistry, negatively impacting wear protection, detergency and more.

Changes Motor Oil Viscosity

Finally, ATF can alter the viscosity of the oil, reducing wear protection.

Viscosity is the oil’s most important property, influencing wear protection and fuel efficiency. Increasing or decreasing viscosity by adding a little transmission fluid in oil to clean sludge can lead to increased engine wear.

Use An Engine Flush Instead

If you want effective sludge removal and cleaning power, we recommend using AMSOIL Engine & Transmission Flush. It helps to restore fuel economy, increase operating efficiency and reduce emissions in gasoline and diesel engines, and automatic transmissions. Its potent, detergent-based formula cleans sludge and deposit build-up.

AMSOIL Engine & Transmission Flush

  • Prepares engines and transmissions for new oil
  • Removes deposits and sludge for improved efficiency, fuel economy and lower emissions
  • Prolongs vehicle life
  • Detergent-based formula is environmentally friendly
  • Compatible with seals and gaskets
  • Works in one treatment
  • Easily disposed of with waste oil

Benefits For Gasoline And Diesel Engines

  • Helps loosen sticky valves and rings, minimizing blow-by and reducing emissions
  • Helps quiet lifter noise
  • Promotes lower operating temperatures through sludge removal

Benefits For Automatic Transmissions

  • Cleans deposits in oil cooler and ports
  • Helps unclog fluid passages
  • Cleans deposits and varnish from clutch plates, helping improve efficiency
  • Promotes smoother operation and transmission life through reduced shift delay

How Often Should Auto Transmission Fluid be changed?

How Often Should I Change Transmission Fluid?

well, um, ahh huh,  well  let’s see… How often to change transmission fluid depends on several factors Sonny outlines in this post.

_by Sunny Pruitt|June 21, 2022

Motorists sometimes ask, “How often should I change transmission fluid?” It depends on your vehicle and driving habits. Recommended transmission fluid changes run the gamut from every 30,000 miles (48,000 km) to never. Yeah, that’s right. Here are some tips for determining how often to change transmission fluid.

Change Transmission Fluid: How Often? Check Your Owner’s Manual

Original equipment manufacturer (OEM) recommendations for how often to change automatic transmission fluid cover a wide mileage range, depending on year, make and model.

Plus, if your driving habits are like most motorists and fall under the “severe” designation (towing, hauling, daily short trips less than 10 miles, etc.), many OEMs recommend changing transmission fluid more frequently.

Here are just a few examples to illustrate the disparity among vehicle makes and models.

Year/Make/Model Normal Service Severe Service
2021 RAM* 1500 Never (filled-for-life transmission) Change if the fluid becomes “contaminated”
2021 Chevy* Silverado* Never (filled-for-life transmission) Every 45,000 miles (72,000 km)
2021 Ford* F-150 150,000 miles (240,000 km) 150,000 miles (240,000 km)
2003 Honda* CR-V* 90,000 miles (145,000 km) 30,000 miles (48,000 km)

These differences illustrate the importance of checking the recommendations in your owner’s manual. It’ll provide maintenance recommendations, typically in a table in the back. Many OEMs provide digital owner’s manuals online, so if you’ve lost yours, try a quick search.

A quick word on “filled-for-life” transmissions.

They’re becoming more prevalent as OEMs seek ways to alleviate motorists from unwanted maintenance. They sound like all upside, but it’s important to change fluid in these units, particularly if you tow or haul.

They’re supposed to last the life of the vehicle, but what do you suppose will happen if the transmission fails once the warranty expires? You’re going to get stuck with a hefty repair bill, that’s what. Be proactive and change fluid at least once during its lifetime.

Change Transmission Fluid: How Often? Go By The Book

Start with the recommendations in your owner’s manual.

But, how many of us dutifully follow them down to the mile? But as you know most drivers completely forget about their transmission until it begins to shift hard, jerk hard jerk hesitate. Out of sight, out of mind, right?

Not good, especially if you tow or haul. But the interval does depend on the abuse and the quality of the fluid.

Heat Kills Transmissions

Over time, transmission fluid oxidizes (chemically breaks down). High heat generated from towing and hauling speeds the process.

Fluid that has broken down can cause sludge and varnish to form, which clogs narrow oil passages and contributes to clutch glazing. Soon, your vehicle can begin to shift poorly.

In these cases, wouldn’t it be great to use a transmission fluid formulated with reserve protection against heat in case life gets in the way of recommended maintenance?

Get Reserve Heat Protection For Your Transmission

AMSOIL Signature Series Synthetic Automatic Transmission Fluid’s built-in reserve protection means it lasts for 2X the OEM’s severe-service drain interval. That means you can rest assured your transmission is protected, even if service is delayed.

Symptoms Of Low Transmission Fluid

It’s not just heat that leads to poor shifting. Low transmission fluid can also present a number of problems, including…

  • Inconsistent, jerky shifts
  • Hesitation
  • Surging
  • Increased transmission temperatures

Low Transmission Fluid = Poor Shifting

Transmission fluid serves a number of vital functions, one of which is to act as a hydraulic fluid to enable shifting.

When your vehicle’s computer tells the transmission to change gears, hydraulic pressure (provided by the fluid) squeezes a series of plates together inside a clutch pack to connect the engine to the transmission output shaft and route power to the wheels.

Low transmission fluid can also prevent the torque converter from filling completely, which reduces torque transfer and causes hesitation and lost power. In extreme cases, the vehicle won’t even move unless you rev up the engine.

How Much Transmission Fluid Do I Need?

How much transmission fluid your vehicle needs ranges from as few as 8-9 quarts for small passenger vehicles to more than 20 quarts for heavy-duty trucks.

As you do when determining how often to change transmission fluid, check your owner’s manual for the transmission fluid capacity.

You can also check the AMSOIL Product Guide, which shows how much transmission fluid your car needs for most makes and models.

Also do you know if you need to use a flushing agent? Amsoil engine and transmission flush is a mild detergent flush but it’s used when you are going to evacuate all the fluid. Restores friction capabilities of the clutched. Best before adjusting the trans when you have over 160,000 miles.

Low Transmission Fluid Can Invite Wear

Transmission fluid also lubricates the gears, clutch plates and seals. It forms a protective layer between meshing gear teeth that prevents metal-to-metal contact and helps reduce wear.

It helps prevent wear on the clutch plates, which bear significant friction during gear shifts. The fluid also lubricates seals and keeps them pliable so they don’t dry out and leak. Find out all the tasks transmission fluid must perform here.

Low fluid can prevent formation of a strong, consistent lubricating film on components, inviting wear. Foam bubbles can collapse when they pass between gear teeth, allowing metal-to-metal contact and further accelerating wear.

Always Check Your Transmission Fluid – Look at the color too

To keep your vehicle running – and shifting – at peak performance, check the fluid about once a month to ensure the correct level. Check out this post on how to check your transmission fluid. If the fluid is consistently low, visit a mechanic to find out why and have the problem fixed.

So, when determining how often to change transmission fluid, follow the recommendations in your owner’s manual. For added peace of mind in case you surpass those recommendations, you can rely on AMSOIL synthetic transmission fluid to deliver reserve protection. Do you know if it has to be warmed up and running?

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