| Product Code | Package Size | Unit of Measure |
|---|---|---|
| FLSHCN-EA | 16 oz. Bottle | Each |
| FLSHCN-CA | 16 oz. Bottle | Case of 12 |
| FLSH55-EA | 55 Gallon Drum | Each |
AMSOIL Engine and Transmission Flush prepares gasoline and diesel engines and automatic transmissions for new oil by dissolving sludge, varnish, and deposits in a single treatment. It is the first step toward restoring performance in neglected or poorly maintained vehicles.
Engines and transmissions accumulate harmful deposits over time. Stop-and-go driving, short trips, prolonged idling, towing, fuel dilution, and oxidized oil all contribute to sludge buildup that restricts oil flow and degrades performance. In automatic transmissions, varnish forms on clutch plates and clogs narrow fluid passages, leading to hesitation, erratic shifting, and eventually clutch glazing. The result is reduced fuel economy, higher operating temperatures, increased oil consumption, and shortened equipment life.
DISSOLVES SLUDGE AND RESTORES OIL FLOW
Sludge settles in narrow oil passages and starves critical components of lubrication, particularly in the upper valvetrain area. AMSOIL Engine and Transmission Flush uses a potent combination of light base-oil technology, detergents, and dispersants to dissolve and suspend these deposits so they drain out with the old oil. This is especially valuable in high-mileage engines or vehicles with unknown maintenance histories, where accumulated sludge may be restricting oil flow to camshafts, lifters, and valve springs. Removing that buildup promotes lower operating temperatures and helps quiet noisy lifters.
LOOSENS STICKY VALVES AND RINGS
Carbon deposits on piston rings and valve stems cause blow-by, increased oil consumption, and elevated emissions. A single 16 oz. treatment of AMSOIL Engine and Transmission Flush helps loosen sticky valves and rings, reducing blow-by and restoring compression. For anyone dealing with oil burning, fouled spark plugs, or gradually declining fuel economy in a gasoline or diesel engine, flushing before an oil change addresses the root cause rather than just masking it with fresh oil.
CLEANS TRANSMISSION CLUTCH PLATES AND FLUID PASSAGES
Automatic transmissions are particularly sensitive to deposit buildup. Varnish on clutch plates causes shift delay and hesitation, and clogged oil cooler passages reduce the transmission's ability to shed heat. AMSOIL Engine and Transmission Flush cleans deposits and varnish from clutch plates, unclogs fluid passages, and cleans deposits from the oil cooler and ports. The result is smoother shifting, improved transmission efficiency, and longer transmission life. This makes it a practical pre-flush before switching to AMSOIL Signature Series Multi-Vehicle Synthetic Automatic Transmission Fluid or any other quality ATF.
SAFE, DETERGENT-BASED FORMULA
Many engine flush products use harsh solvents that can damage seals and gaskets. AMSOIL Engine and Transmission Flush is detergent-based, compatible with seals and gaskets, and safe for use with both petroleum and synthetic oils. Because it is detergent-based rather than solvent-based, it can be easily disposed of with waste oil. It delivers results in one treatment, but it is safe enough to use at every oil change as part of routine maintenance.
Applications and Compatibility
AMSOIL Engine and Transmission Flush is recommended for gasoline engines, diesel engines, and automatic transmissions. It is compatible with both petroleum and synthetic motor oils and transmission fluids. Do not use in differentials. It is not recommended for transmissions that do not have a removable pan or access to the transmission filter.
Directions for Use
For engines, add one full 16 oz. bottle to the engine oil fill port, idle for 10-15 minutes, then immediately drain the oil. Allow adequate time for the system to drain completely, replace the oil filter, and refill with new engine oil. For automatic transmissions, engage the emergency brake, add one bottle to the transmission fill port, idle for 10-15 minutes while shifting through drive and reverse, then drain the entire transmission and torque converter. The transmission filter must be changed before refilling with new fluid. Do not place the vehicle under heavy load during the flush.
For larger sumps, use the following treat rates:
| Sump Capacity | Bottle(s) Required | Total Ounces |
| Up to 10 quarts | 1 bottle | 16 oz. |
| 10-20 quarts | 2 bottles | 32 oz. |
| 20-30 quarts | 3 bottles | 48 oz. |
| 30-40 quarts | 4 bottles | 64 oz. |
What vehicles and equipment can I use AMSOIL Engine and Transmission Flush on?
AMSOIL Engine and Transmission Flush (FLSHCN) is engineered for use in both gasoline and diesel engines as well as automatic transmissions. It covers a wide range of equipment types including auto/light truck, motorcycle, ATV, UTV, snowmobile, marine outboard, PWC, heavy-duty on-road and off-road vehicles, agriculture equipment, and powersports applications. However, it should not be used in differentials, and AMSOIL does not recommend flushing transmissions that do not have a removable pan or access to the transmission filter.
Does AMSOIL Engine and Transmission Flush actually improve fuel economy and reduce emissions?
Yes. AMSOIL Engine and Transmission Flush helps restore fuel economy, increase operating efficiency, and reduce emissions by dissolving and dispersing sludge, varnish, and deposits that accumulate over time. In engines, it loosens sticky valves and rings to minimize blow-by and reduce emissions, while also promoting lower operating temperatures through sludge removal. In automatic transmissions, it cleans deposits from clutch plates and unclogs fluid passages, reducing shift delay and improving overall efficiency.
What is the formula technology behind AMSOIL Engine and Transmission Flush and how does it work?
AMSOIL Engine and Transmission Flush uses an advanced detergent-based formula built on light base oil technology combined with powerful detergents and dispersants. Unlike solvent-based flush products, this formulation dissolves and disperses sludge, varnish, and deposits safely in a single treatment. Because it is detergent-based rather than solvent-based, it is environmentally friendly and can be easily disposed of with waste oil rather than requiring special handling.
How does AMSOIL Engine and Transmission Flush compare to other engine flush products?
Unlike many flush products on the market, AMSOIL Engine and Transmission Flush features a multi-use formulation that works in both engines and automatic transmissions, eliminating the need for separate products. Its detergent-based formula provides safe cleaning action that is compatible with seals and gaskets, whereas some competing flushes use harsh solvents. It delivers one-treatment results, can be disposed of with regular waste oil, and is safe enough to be used at every oil change interval.
How do I use AMSOIL Engine and Transmission Flush and how often should I use it?
For engines, add the entire 16 oz. bottle to the engine oil fill port, idle the engine for 10-15 minutes, then immediately drain the oil completely, replace the oil filter, and refill with new engine oil. For automatic transmissions, engage the emergency brake, add the full bottle to the transmission fill port, idle for 10-15 minutes while shifting through drive and reverse (do not place the vehicle under heavy load), then drain the entire transmission and torque converter and change the filter before refilling with new fluid. Although it delivers results in one treatment, AMSOIL states it is safe enough to be used at every oil change.
Is AMSOIL Engine and Transmission Flush safe for engine seals, gaskets, and both synthetic and conventional oils?
Yes, AMSOIL Engine and Transmission Flush is specifically formulated to be compatible with seals and gaskets, so it will not cause leaks or damage rubber components. It is also compatible with both petroleum and synthetic oils, making it suitable for preparing poorly maintained equipment for installation of new oil regardless of the oil type previously used. Its detergent-based cleaning action is designed to be safe on internal engine and transmission parts while still effectively removing sludge and deposits.
Product Details PDF - AMSOIL ENGINE AND TRANSMISSION FLUSH
