# Leaking Transmission, is it a good idea to put in a store bought sealer **URL:** \ **Category:** General Discussion\ **Tags:** mercedes-benz, sl-class\ **Created:** [June 24, 2020, 2:39pm UTC](https://community.cartalk.com/t/leaking-transmission-is-it-a-good-idea-to-put-in-a-store-bought-sealer/166283 "2020-06-24T14:39:39Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![paul\_168510](https://avatars.discourse-cdn.com/v4/letter/p/e56c9b/32.png) [@paul\_168510](https://community.cartalk.com/u/paul_168510)\ **Post date:** [June 24, 2020, 2:39pm UTC](https://community.cartalk.com/t/leaking-transmission-is-it-a-good-idea-to-put-in-a-store-bought-sealer/166283/1 "2020-06-24T14:39:39Z")
I’ve a 1987 merc 300 SL & the transmission is leaking. is it ok to put one of those sealers. if so is there a recommended brand. Thanks Paul Car Novice ---
**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:** [June 24, 2020, 3:19pm UTC](https://community.cartalk.com/t/leaking-transmission-is-it-a-good-idea-to-put-in-a-store-bought-sealer/166283/2 "2020-06-24T15:19:18Z")
Where is the leak, exactly? Also, that model wasn’t imported by MB into the US. Where are you? ---
**Author:** ![paul\_168510](https://avatars.discourse-cdn.com/v4/letter/p/e56c9b/32.png) [@paul\_168510](https://community.cartalk.com/u/paul_168510)\ **Post date:** [June 24, 2020, 3:27pm UTC](https://community.cartalk.com/t/leaking-transmission-is-it-a-good-idea-to-put-in-a-store-bought-sealer/166283/3 "2020-06-24T15:27:01Z")
looks like it’s right under the gear box. I have never lifted up the car, so I wouldn’t know exactly, ---
**Author:** ![db4690](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/db4690/32/2583_2.png) [@db4690](https://community.cartalk.com/u/db4690)\ **Post date:** [June 28, 2020, 5:08am UTC](https://community.cartalk.com/t/leaking-transmission-is-it-a-good-idea-to-put-in-a-store-bought-sealer/166283/4 "2020-06-28T05:08:31Z")
Why don’t you figure out what the leak is, for starters if it’s the kick-down solenoid seal(s) . . . for example . . . that could be fixed without removing the transmission There’s also a few servo cover seals that can be replaced without removing the transmission, if memory serves However, if it’s the front pump seal . . . which would not be surprising, given the age of the car . . . that’s not something that could be fixed properly without removing the transmission ---
**Author:** ![bcohen2010](https://avatars.discourse-cdn.com/v4/letter/b/779978/32.png) [@bcohen2010](https://community.cartalk.com/u/bcohen2010)\ **Post date:** [June 28, 2020, 5:14am UTC](https://community.cartalk.com/t/leaking-transmission-is-it-a-good-idea-to-put-in-a-store-bought-sealer/166283/5 "2020-06-28T05:14:51Z")
There are really only two times when it makes sense to put sealant into an automatic transmission: “never” and “not ever”. At all other times, you should do one of two things: find and repair the leaking seal/gasket/hose connection, or just keep adding approved transmission fluid as needed. ---
**Author:** ![paul\_168510](https://avatars.discourse-cdn.com/v4/letter/p/e56c9b/32.png) [@paul\_168510](https://community.cartalk.com/u/paul_168510)\ **Post date:** [July 5, 2020, 3:56pm UTC](https://community.cartalk.com/t/leaking-transmission-is-it-a-good-idea-to-put-in-a-store-bought-sealer/166283/6 "2020-07-05T15:56:54Z")
Thank you. Should I go to a transmission shop or wait till I find someone that’s works on old cars here. I’ve a starting issue too, I’m told it’s the cold starting valve, but could be any part before or after that’s causing the valve to fail. Paul Griffith ---
**Author:** ![paul\_168510](https://avatars.discourse-cdn.com/v4/letter/p/e56c9b/32.png) [@paul\_168510](https://community.cartalk.com/u/paul_168510)\ **Post date:** [July 5, 2020, 3:59pm UTC](https://community.cartalk.com/t/leaking-transmission-is-it-a-good-idea-to-put-in-a-store-bought-sealer/166283/7 "2020-07-05T15:59:22Z")
Thank You. You took me off the fence, I’ll wait till I can find a guy that can work on these cars. I’ve a cold starting issue too. Which is less no because it’s hot. Paul Griffith ---
**Author:** ![db4690](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/db4690/32/2583_2.png) [@db4690](https://community.cartalk.com/u/db4690)\ **Post date:** [July 5, 2020, 4:04pm UTC](https://community.cartalk.com/t/leaking-transmission-is-it-a-good-idea-to-put-in-a-store-bought-sealer/166283/8 "2020-07-05T16:04:21Z")
Cold start valve, huh? It’s a distinct possibility, You need somebody that can hook up a fuel pressure gauge to a Bosch KE-Jetronic and interpret the results correctly That probably rules out a lot of shops and/or mechanics