AMSOIL Engine and Transmission FlushSafely removes deposits in gasoline or diesel engines and automatic transmissions for a return to “like new” performance and efficiency.

Buy AMSOIL Engine and Transmission Flush in Canada or the USA at wholesale. Request a price list using the contact form on your right.

Engine and Transmission Flush package sizes include:
16-oz. Bottle
16-oz. Bottles (case of 12)
5-gallon pail
55-gallon drum

AMSOIL Engine and Transmission Flush is a powerful and inexpensive, but very safe formula that performs a complete internal clean-up of gasoline or diesel-powered engines and automatic transmissions. When added during the oil change procedure, AMSOIL Flush quickly dispatches sludge, varnish and dirt for cooler operation and a return to original power and efficiency. This product is safe and compatible with synthetic, synthetic-blend and regular engine oil and safe with all gasket and seal materials.

Why Perform an Engine or Transmission Flush?

If you have purchased a used vehicle or if you are switching from conventional oil to AMSOIL Synthetic Oil for the first time, performing a flush procedure is an inexpensive way to start out with a “clean slate”. Regular motor oils are more prone to oxidizing which can produce sludge and varnish. These contaminants can block passages, coat valves and obstruct coolers. AMSOIL synthetic oil is inherently high in detergents, so they will eventually clean up many of these foreign materials. It is a great idea to clean out these deposits in advance, rather than have your new oil do all the work.

What Causes Engine and Transmission Deposits?

  • Oxidized oil. Conventional engine oil and ATF are especially prone.
  • Short trips
  • Excessive idling
  • Ingested dirt
  • Condensation
  • Fuel dilution

What Are the Benefits of an Engine and Transmission Flush?


  • Frees sticky valves, lifters and piston rings which promotes quiet operation and can occasionally reduce oil consumption.
  • Restores fuel mileage
  • Brings back lost power
  • Clean engines run cooler, quieter, more efficiently and last longer


  • Cleans up coolers, passages, clutch plates and valve bodies
  • Brings back smooth shifting
  • Reduces hesitation and shudder due to varnish deposits.
  • Offers cooler operation and longer component life.
  • Restores fuel economy


  • Suitable for flushing either gasoline or diesel engines and automatic transmissions.

Not suitable for the following:

  • Not suitable for flushing manual transmissions or transaxles, CVT transmissions.
  • Not suitable for motorcycles, ATV’s or small engines.
  • Not compatible with motorcycle transmissions or wet clutches.

Application Rate For AMSOIL Engine and Transmission Flush

On the left is the oil capacity and on the right is the number of 473 ml (16 oz.) bottles of AMSOIL Engine and Transmission Flush required.

  • Up to 9.46 litres (10 US quarts) – One Bottle
  • 9.46 to 18.9 litres (10 to 20 US quarts) – Two Bottles
  • 18.9 to 28.4 litres (20 to 30 US quarts) – Three Bottles
  • 28.4 to 37.85 litres (30 to 40 US quarts) – Four Bottles

Instructions for AMSOIL Engine and Transmission Flush

Caution before starting: Both the engine and transmission flush processes require extensive engine idling. Only idle the engine in an adequately ventilated area. Inhalation of carbon monoxide from engine exhaust is deadly!

Flushing an Engine

  1. With engine shut down, pour AMSOIL Engine and Transmission Flush into engine oil fill hole.
  2. Start engine and let it idle for 10 to 15 minutes. Do not drive the vehicle or place it under any load.
  3. Then stop engine and drain the engine oil and remove the oil filter.
  4. While every effort should be made to completely drain the engine oil, small amounts of this product remaining in the engine is harmless.
  5. Install new oil filter and engine oil

Flushing an Automatic Transmission

Important: Do not use this product on transmissions that do not have a removable pan or accessible transmission oil filter.

This product can be used with commercial transmission flushing machines. Note that the pan must still be removed and transmission oil filter must be replaced.

  1. Inserts blocks in both the front and back of all four wheels and apply emergency brake.
  2. Add AMSOIL Engine and Transmission Flush to transmission oil fill hole.
  3. Start engine and run on idle for 15 minutes. During this period, shift the transmission between drive and reverse several times.
  4. Do not place the vehicle under load during this portion of the process.
  5. Completely drain the transmission and torque converter.
  6. While every effort should be made to completely drain the transmission fluid, small amounts of this product remaining in the transmission is harmless.
  7. Important: Replace the transmission oil filter. If a screen is used rather than a replaceable filter, clean the screen after ATF has been drained.
  8. Refill the transmission with new automotive transmission fluid.

How Often Can AMSOIL Engine and Transmission Flush Be Used?

AMSOIL Engine and Transmission Flush is safe enough to use with every engine or automatic transmission oil change. As engine oil changes are performed far more frequently than ATF changes, doing engine oil flushes every time is likely unnecessary. This is especially the case if AMSOIL Synthetic Motor Oils are used. AMSOIL Synthetics are much more resistant to oxidation and deposit formation than regular engine oils.

Automatic Transmission Clutch Plates Before Flush

Above are transmission clutch plates prior to the flush process. Note the varnish and discolored coating.

Automatic Transmission Clutch Plates After Flush

These are the same clutch plates, post-flush procedure. Note that the varnish is dramatically reduced.

Engine Cylinder Head Before Flush

Above is a cylinder head prior to the AMSOIL flush procedure. Note the extensive deposit formations.

Cylinder Head After AMSOIL Engine & Transmission Flush

The cylinder head after the AMSOIL Engine and Transmission Flush process is considerably cleaner.

AMSOIL Engine and Automatic Transmission Flush
A safe and effective flush product for removing sludge, varnish and deposits from gasoline or diesel engines and automatic transmissions.
Manufacturer: AMSOIL
Model: Engine and Automatic Transmission Flush
Product ID: FLSH