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1 Transmission Cocktail Mix

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Product Description

FINALLY!!!....a place to get all the ingredients for the Transmission Cocktail! This cocktail is the famous transmission oil mix that many many Subaru owners have used to fix that bad shifting/grinding manual transmission.

No more searching around town trying to find all the ingredients and not being able to find them all...GrimmSpeed™ has them all in stock and ready to ship out to you.

If you'd like a smoother shifting gearbox, this is for you.

NOTE: This mix is only ideal for all 5 Speed Subaru Transmissions and has been updated to include Heavyweight Shockproof


When filling up your transmission you will use ALL of Penzoil, Heavyweight Shockproof, and 1 full bottle of the Castrol Hypoy C, then you use approx. 1/3 to 1/2 of the remaining Hypoy C until the transmission is full.

Product Reviews

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Product Reviews

Showing reviews 1-10 of 36 | Next

  1. fixed my issues

    Posted by nick

    My car had a very light grind going into 3rd at higher rpms and was well over due for the oil change after I changed to a simple Mobil 1 gl5 change the grind got worse and now every gear was not smooth this was my last ditch effort before a new trans. It worked perfect smoother then day one when I bought the car.

  2. Works Great

    Posted by Unknown

    We used it in a 2011 WRX transmission and it drives and shifts a lot smoother.

  3. Went down smooth!

    Posted by

    It is the best thing that's ever been in my trans. Smooth as butter now!!

  4. let hope it will last

    Posted by Justin

    I just hope with switching to the heavy it won't thin out like the other cocktail.

  5. let hope it will last

    Posted by Justin

    I just hope with switching to the heavy it won't thin out like the other cocktail.

  6. Sooooo Much better!!

    Posted by David

    I bought the Cocktail for my 02 WRX as it was grinding in 1st a lot. I followed the instructions and took it easy for awhile and went through every gear and in short order the shifting became MUCH smoother. Highly recommend this.

  7. Great

    Posted by Unknown

    Changed the fluid in my 01 RS. Stock tranny with an 05 wrx engine swap. Seems to shift smoother and I'm really happy with the mix.

  8. great product!

    Posted by Tyler Minnig

    Love the simplicity of the cocktail. Works amazing in my built 5 speed

  9. Waste of money

    Posted by Jacob

    I purchased this cocktail to see how it would fair. I needed to drain the transmission anyhow to replace a seal and cv-axles. after a month or so of daily driving accompanied by some spirited driving my synchronizers aren't happy with this mix. after paying almost $80 between the cocktail & shipping I am very disappointed in this product. It may work better for unmodified vehicles but I definitely don't recommend it.

  10. Not snake oil!!!

    Posted by Aaron L

    Use to grind always in reverse and when going into 5th after a hard pull. A bit of cocktail and not a peep for months!

Showing reviews 1-10 of 36 | Next