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AMSOIL Engine and Transmission Flush

Product code : FLSHCN-EA

Prepares Engines and Transmissions For New Oil

  • Engineered for gasoline and diesel engines and automatic transmissions
  • Helps restore fuel economy, increase operating efficiency and reduce emissions
  • Potent, detergent-based formula cleans sludge and deposit build-up, promoting reduced oil consumption

AMSOIL Engine and Transmission Flush



AMSOIL Engine and Transmission Flush (FLSH) helps 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, promoting reduced oil consumption. AMSOIL Engine and Transmission Flush is safe on parts and can be easily disposed of with waste oil.

Restores Vehicles to Like-New
New engines and transmissions run more efficiently, but over time they gather harmful deposits that cause power and performance loss. Stop-and-go driving, prolonged idling, short trips that do not allow the engine to reach full operating temperature, towing, the ingestion of air-borne dirt, fuel dilution, water condensation and oxidized oil all can promote sludge build-up in motor oil and transmission fluid. As it settles, sludge clogs narrow oil passages, restricting oil flow to vital parts, especially the upper valve train area.

In transmissions, deposits can form on clutch plates, causing hesitation and erratic shifting. Ultimately clutch glazing can set in, reducing the life of the transmission. Deposits in engines and transmissions can accelerate wear, causing power loss and increased fuel consumption.

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

AMSOIL Engine and Transmission Flush Benefits
Unlike many flush products, AMSOIL Engine and Transmission Flush features a multi-use formulation that dissolves and disperses sludge, varnish and deposits in both engines and automatic transmissions. Due to its detergent-based formulation, it can be easily disposed of with waste oil, making it more user-friendly. Its advanced formula of light base oil technology, powerful detergents and dispersants provides safe cleaning action. AMSOIL Engine and Transmission Flush is compatible with both petroleum and synthetic oils, preparing poorly maintained equipment for installation of new oil. It represents the first step toward restoring neglected equipment to top-notch performance. AMSOIL Engine and Transmission Flush provides the following benefits in only one treatment:

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
  • Easy disposal

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

Applications
AMSOIL Engine and Transmission Flush is recommended for diesel and gasoline engines, and automatic transmissions. Do not use it in differentials.

Directions for Use
Though it works in one treatment, AMSOIL Engine and Transmission Flush is safe enough to be used at every oil change. If using a flushing machine, follow the manufacturer's recommendation. Otherwise, use the following guidelines:

Engine: Add entire bottle of AMSOIL Engine and Transmission Flush to engine oil fill port. Idle the engine for 10-15 minutes, then immediately drain the oil. Ensure enough time for the system to completely
drain. Remove and replace the engine oil filter. Refill engine with new engine oil in the viscosity grade recommended by the manufacturer.

Transmission: Engage emergency brake. Add entire bottle of AMSOIL Engine and Transmission Flush to transmission oil fill port. Idle for 10-15 minutes; shift through drive and reverse. Do NOT place vehicle under heavy load. Drain entire transmission and torque converter of fluid. FILTER MUST BE CHANGED prior to refilling with new transmission fluid.

NOTE: It is not recommended to flush transmissions that do not have a removable pan or access to the transmission filter.

Automatic transmission clutch plates pre-cleanup.
(above) Automatic transmission clutch plates pre-cleanup. Varnish and glazing is heavy on some of the plates.
Automatic transmission clutch plates after cleanup.
(above) Automatic transmission clutch plates after cleanup with AMSOIL Engine and Transmission Flush reveal lighter glazing and varnish.
Cylinder head pre-cleanup.
(above) Cylinder head pre-cleanup. Note the sludge deposits on and around the valve springs and push rod openings.
Cylinder head after cleanup with AMSOIL Engine and Transmission Flush.
(above) Cylinder head after cleanup with AMSOIL Engine and Transmission Flush. The valve springs and push rod openings are noticeably cleaner, with fewer sludge deposits. The manufacturer's stamping is more easily seen.

AMSOIL Engine and Transmission Flush

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AMSOIL Engine and Transmission Flush

  • 5 star rating
    Well, Flush It
    By  X,  a  Verified Buyer  from  AK  on  April 13, 2025
    If you catch yourself looking at this product, chances are you've changed the oil in your vehicle plenty a time before, but want the ultimate clean for your internals. Although Amsoil has arguably the best detergent/additives package and oil could have, using their ultimate detergent in a bottle is just extra security for changing the oil. Truck just hit 115000 miles and I wanted to do a full flush, directions were simply, drained as normal with the old oil, I could definitely tell that the oil was not alone, black deposits came out too, nothing magnetic (magnetic pickup wouldn't attract/repel). Get some while you're looking at it, can't hurt, definitely could help!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great
    By  BRADLEY,  a  Verified Buyer  from  Kansas City   on  April 07, 2025
    Having a turbo charged Honda civic this stuff is great I use it before every oil change. I feel like it extra cleans out all the junk and car runs really smooth at 80k miles.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great
    By  CHRISTOPHER,  a  Verified Buyer  from  Louisiana  on  April 07, 2025
    Used once at 170k miles oil was clean prior to flush but after flush it was black definitely worked
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Flush
    By  ARMAND,  a  Verified Buyer  on  April 04, 2025
    Does what it’s meant to do
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Amazing!
    By  AmsOil Fanboy,  a  Verified Buyer  from  Northern California  on  April 01, 2025
    I use this with every oil change. I have yet to try this on my manual transmission gear oil flush, but I'm sure it will help. This is the absolute Best flush ever!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Engine flush
    By  JASON,  a  Verified Buyer  from  Cochrane AB   on  March 31, 2025
    Only used this in the engine and everyone change oil I utilize 1 bottle in either gas or diesel. It breakdowns the oil to a watered state so I can get all of it out + debris that flows out with it. It’s great stuff.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Flush
    By  TIM,  a  Verified Buyer  from  AZ  on  March 04, 2025
    At frist I didn't think it was working but the the 3rd time I pulled dipstick out I was amazed at the results
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Seems to do the job
    By  SEAN,  a  Verified Buyer  from  Michigan  on  February 16, 2025
    I have a 2017 grand Cherokee with 198000mes on it. I tried this and you should have seen the stuff come out of the oil pan drain hole. I will most definitely be using again.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    It really works
    By  VINCENT,  a  Verified Buyer  from  Texas  on  February 11, 2025
    The first time I used this I was shocked how much sludge came out of my oil pan. Some people would say you don't change your oil enough well I do change it every time the oil starts turning black. Probably why I have 254k miles on a 4.3 liter vortex and still runs strong.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Makes Changes Quick, and More Effective
    By  ROBERT,  a  Verified Buyer  from  Augusta GA  on  February 02, 2025
    I use this on every other oil change, and it makes my changes quicker as it lightens the oil, and also provides a thorough cleaning to make sure that old oil and particles come out during the change.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?