# Will ATF damage my 2009 Subaru Forester manual trans?

**URL:** <https://community.cartalk.com/t/will-atf-damage-my-2009-subaru-forester-manual-trans/140186>\
**Category:** Maintenance/Repairs\
**Tags:** forester, subaru\
**Created:** [May 12, 2019, 1:46pm UTC](https://community.cartalk.com/t/will-atf-damage-my-2009-subaru-forester-manual-trans/140186 "2019-05-12T13:46:29Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![MarkBendekovits](https://avatars.discourse-cdn.com/v4/letter/m/ecae2f/32.png) [@MarkBendekovits](https://community.cartalk.com/u/MarkBendekovits)\
**Post date:** [May 12, 2019, 1:46pm UTC](https://community.cartalk.com/t/will-atf-damage-my-2009-subaru-forester-manual-trans/140186/1 "2019-05-12T13:46:29Z")

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I accidently added a small amount of automatic transmission fluid in my manual transmission. Will it damage the transmission? What should I do?

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**Author:** ![circuitsmith](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/circuitsmith/32/40376_2.png) [@circuitsmith](https://community.cartalk.com/u/circuitsmith)\
**Post date:** [May 12, 2019, 2:29pm UTC](https://community.cartalk.com/t/will-atf-damage-my-2009-subaru-forester-manual-trans/140186/2 "2019-05-12T14:29:53Z")

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No worries, ATF and trans oil are very similar.  
In fact some manual trans specify ATF.

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**Author:** ![ok4450](https://avatars.discourse-cdn.com/v4/letter/o/e9bcb4/32.png) [@ok4450](https://community.cartalk.com/u/ok4450)\
**Post date:** [May 12, 2019, 9:54pm UTC](https://community.cartalk.com/t/will-atf-damage-my-2009-subaru-forester-manual-trans/140186/3 "2019-05-12T21:54:23Z")

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A manual should not be low unless there is a leak so verify that first.

A 75/90 weight gear oil is recommended. There is a difference between a normal manual transmission and the transaxle (proper term) in your Subaru. The Subaru transaxle includes a ring and pinion gear set to power the front axles so therefore the heavier weight oil.

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**Author:** ![Rod-Knox](https://avatars.discourse-cdn.com/v4/letter/r/a183cd/32.png) [@Rod-Knox](https://community.cartalk.com/u/Rod-Knox)\
**Post date:** [May 12, 2019, 11:30pm UTC](https://community.cartalk.com/t/will-atf-damage-my-2009-subaru-forester-manual-trans/140186/4 "2019-05-12T23:30:35Z")

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The ring and pinion may have straight cut gears and not require hypoid gear oil.

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**Author:** ![Manolito](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/manolito/32/3070_2.png) [@Manolito](https://community.cartalk.com/u/Manolito)\
**Post date:** [May 13, 2019, 12:22am UTC](https://community.cartalk.com/t/will-atf-damage-my-2009-subaru-forester-manual-trans/140186/5 "2019-05-13T00:22:52Z")

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I cannot be certain, but it appears that your manual transmission uses ATF. If you have your owners manual, you can check.

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**Author:** ![texases](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/texases/32/862_2.png) [@texases](https://community.cartalk.com/u/texases)\
**Post date:** [May 13, 2019, 12:41am UTC](https://community.cartalk.com/t/will-atf-damage-my-2009-subaru-forester-manual-trans/140186/6 "2019-05-13T00:41:51Z")

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Check out Forester forums. Looks like yours needs the “HP” manual fluid.

How much is “a small amount of” ATF?