How to Fix a Manual Transmission Leak

Manual Transmission ShiftFirst let me compliment you on having a manual transmission in your car.  Since the advent of the automatic transmission, cars with automatics have been thought of as more luxurious and fancy.  Automatic transmissions are often seen as upgrades or something you wouldn’t consider going without if you could afford it.  Automatic transmissions do have their place.  Places like stop and go traffic, the commuter who likes to finish breakfast in the car and maybe for those who don’t really enjoy driving all can be made easier with an automatic.  But having a manual transmission can add so much to the driving experience.  It gives the driver the ultimate control over his vehicle, and a good drive will always outperform the best computer controlled automatic transmission.  On top of being fun to drive, manual transmissions often provide better fuel mileage and can last significantly longer than automatic transmissions.

Really only 2 things can cause a manual transmission to fail early.  Poor driving habits, and a lack of good transmission fluid.  Grinding gears, power-shifting and poor clutch work can all put a lot of stress on a manual transmission.  Through training, or at least trial and error, most drivers get past those bad habits quickly and your manual transmission will last for years.  Low fluid level however can still be a quick killer for any manual transmission no matter how skilled the driver is.  Unlike an automatic transmission, manual transmissions only use the transmission fluid as a lubricant rather than a working or hydraulic fluid.  Because of this, most manual transmissions simply use oil, usually called gear oil, which is similar to engine oil, just thicker.  Some manual transmissions may use a different lubricant to help protect and lubricate the synchronizers.  Either way, if this lubricating fluid gets lower than it should be the transmission can build heat very quickly and things can go wrong in a hurry.  If a transmission is used with low fluid, bearings can be destroyed, gears can lose teeth and shafts can be destroyed.  If this happens to your transmission, you will likely need more than just a simple rebuild which comes with a high price tag.

Leaking TransmissionUnder normal circumstances the gear oil you put in your manual transmission has no way out.  Unlike your engine, the only way for the oil to get out of your transmission is to leak past a seal or gasket.  Every transmission has multiple shaft seals, one at the input shaft on the engine side of your transmission and one on each of the output shafts, like the drive shaft or axle shafts.  As the input and output shafts spin these seals can wear down over time.  Also, if the vehicle sits unused, the seals can dry out or get distorted from sitting in one position.  Also, many manual transmissions are built with the intention of being easy to rebuild.  This means they are rarely one piece cases but have different sections with gaskets between them.  Over time from heat and use these gaskets can also begin to leak.

It can sometimes be difficult to notice a transmission leak in your manual transmission as they often start slow and since your transmission is one of the lowest points in your car, as you drive the dripping oil will be blown away easily by the wind.  A leaking transmission can be even more dangerous than leaking motor oil since you have a relatively small amount of oil in your transmission.  Most Engines can hold 4-6 quarts of oil while many manual transmissions only hold 1.5-3 quarts so even a small leak can make a difference quickly.

Sealing the leak in your manual transmission doesn’t have to involve a rebuild or even pulling your transmission out of your car, which can be a big project.  Even though the seals and gaskets in your transmission are leaking, they are mostly likely still good, they just need to be restored to their original size and shape.  Adding BlueDevil Transmission Sealer to your manual transmission through the fill plug can do just that!  BlueDevil Transmission Sealer is a specially formulated liquid leak stop agent that will permanently stop your transmission leak by restoring the seals and gaskets in your transmission.  We’re so confident, we guarantee your leak will be sealed!

BlueDevil Transmission Sealer

Pickup BlueDevil Transmission Sealer at any of our partnering local auto parts stores like:

  • Advance Auto Parts
  • AutoZone
  • Bennett Auto Supply
  • CarQuest Auto parts
  • NAPA Auto Parts
  • O’Reilly Auto Parts
  • Pep Boys
  • Fast Track
  • Bumper to Bumper Auto Parts Specialists
  • S&E Quick Lube Distributer
  • DYK Automotive

You can also purchase BlueDevil Transmission sealer directly from BlueDevil here.

Pictures provided by: 4bangerjp.com and www.apsisusa.com

 

51 responses to “How to Fix a Manual Transmission Leak

    1. Chuck-

      Yes, you should add the proper amount of the BlueDevil Transmission Sealer to help stop your leak. One ounce of BlueDevil treats 1 quart of capacity. You should notice results after about 100 miles of driving.

      Feel free to contact us with any questions at 888-863-0426.

      Thank You!

      -BDP

      1. I just put a new seal in my 94 chev c1500 after about 20 miles it started leaking again. A friend says its the bushing n the end of tranny wore out and another seal or anything won’t fix it. With it being a new seal is this stuff possible to stop my leak I can’t afford a transmission right now and can’t find one at that just all honestly will this work fort truck?

        1. Jonathan-

          Thank you for asking about your Chevy C1500. As long as you are not losing fluid too quickly, you would be a good candidate for the product. Keep in mind, you will start to see results after about 100-200 miles of driving.

          Thank you!

          -BDP

  1. Does it have any harmful effect to the transmission, like, should I flush the transmission after the leak is sealed and replace the fluid, so that the residual sealer is purged? I’ve heard of other brands gumming up in the gears if the oil with the sealer in it wasn’t flushed.

    1. Brian-

      No, the BlueDevil Transmission Sealer will not harm the transmission or any other components in any way. The BlueDevil will not thicken or harden at any point. The Transmission Sealer can be left in for the life of the transmission fluid.

      You should add 1 ounce of BlueDevil Transmission Sealer to every 1 quart of fluid capacity.

      Thank You!

      -BDP

        1. John-

          Yes, the BlueDevil Transmission Sealer is compatible and safe to use with syncromesh manual transmission fluid. Feel free to contact our technical support line at 888-863-0426 with any other questions.

          Thank you!

          -BDP

    1. Matt-

      Your Mazda holds 6.1 pints of transmission fluid. You should add 3 ounce of the BlueDevil Transmission Sealer to your transmission. Expect to start noticing results after about 100 miles of driving.

      Thank you!

      -BDP

    1. Miguel-

      You will use one ounce of the BlueDevil Transmission Sealer per quart of transmission fluid in the system of your Ford F150. Feel free to contact our technical support line at 888-863-0426 with any other questions.

      Thank you!

      -BDP

  2. Recently rebuilt my 4 speed transmission in a 1987 C60 Chevrolet dump truck, transmission works great now, discovered a small problem, have a small leak that I cannot see where the transmission is into the bell housing. All of the seals are new, the leak is like a drop or so in a 24 hour period but aggravating, would blue devil be a possible solution to keep from pulling the transmission back out?

    1. Tony-

      Thank you for your question. You will be using one ounce of the BlueDevil Transmission Sealer per quart of fluid in the system. If you have the 4 Speed Automatic, the capacity is about 13 quarts, so would be using 13 ounces of the product.

      Thank you!

      -BDP

    1. Andre-

      You should add 1 ounce of the BlueDevil Transmission Sealer per every 1 quart of capacity. Based on the transmission capacity of your Saturn you should add 5 ounces of the BlueDevil Transmission Sealer. Once the product is added you can expect to start seeing results after about 100 miles of driving.

      Thank you!

      -BDP

  3. I have a 2002 Audi tt Quattro 225hp 6 Speed Transmission. I removed the tranny to replace the clutch and separated the front differential from the transmission and replaced the 3 seals connecting them with OEM products, however I’m noticing some seeping from those seals. What is the capacity of the transmission fluid (synthetic 75W 90) so I can purchase your product and add the correct amount. The fluid runs through the transmission and differential. Will it be safe for this type of setup?. Thank You.

    1. Frank,

      Thanks for your question about your Audi. First we would recommend checking the torque specs on the bolts you tightened around those gaskets to make sure everything is tightened properly. If you still have leaks after that, you can add BlueDevil Transmission Sealer along with the gear oil for your transmission and differential. BlueDevil Transmission Sealer will not significantly raise the fluid level in your transmission so you can add it safely to your transmission now.

      Thanks again for your question!
      -BD Auto Pro

  4. What is all the transmission fluid has already leaked out and the engine is seized up? Will it still help? The gear oil leaked out of the input shaft. They said they put more in but it just poured out.

    1. LMU-

      Based on your description, unfortunately, we would not recommend using the product in this situation. It seems like you are losing fluid a little too quickly, and would probably lose the product before it got a chance to seal.

      Thank you!

      -BDP

  5. My 1994 Mazda B3000 pickup has a manual transmission. However, it uses automatic transmission fluid. The transmission has a capacity of three quarts, and it leaks at a rate of around one quart every 4-6 weeks. The vehicle only has about 105,000 miles on it, so there’s a good chance that it set idle for an extended period of time.

    I’m interested in trying your product, by I need to know…

    1. Will it work on automatic transmission fluid in a standard transmission?

    2. If so, would it be able to stop this rate of leakage?

    Thanks.

    1. Joey-

      Yes, BlueDevil Transmission Sealer will work with Automatic Transmission Fluid in a standard transmission. Based on the capacity, you should use 3 ounces of BlueDevil to treat the Mazda. The leak you have is fairly large but not too large fro what BlueDevil is intended to fix. Once the product is added you can expect to start seeing results after about 100 miles of driving.

      Thank you!

      -BDP

    1. Eric-

      Yes, if the leak is coming around any of the rubber seals or gaskets then BlueDevil will work. Be sure to use the proper amount – add 1 ounce of BlueDevil per every 1 quart of capacity; more is not better. Once added, you can expect to start seeing results after about 100 miles of driving.

      Thank you!

      -BDP

  6. I have a 2004 BMW 530i and I noticed it has a slow leak I purchased the blue devil transmission seal 16oz. I could only use less than half of the bottle. Do I have to use as recommended ?

    1. Deidra-

      Thank you for asking about your BMW 530i. Yes, it is very important to use the product as recommended. Doing so will ensure the best possible results and give yourself the best chance of sealing your leak(s). You should be using one oz of the Transmission Sealer per quart of fluid in the system.

      Thank you!

      -BDP

  7. Thanks for the information about transmission leaks! My car has one and I need to get it fixed fast! From reading your article I’ve realized that I’m not talented enough to fix it. I’m just going to take it to the shop.

  8. My 2001 dodge stratus manual transmission is leaking. It looks like right where the engine and transmission meet. I thought it was the rear main seal but I smelled the fluid and it’s definitely gear fluid so would this work?

    1. MeShan-

      Thank you for asking about your Dodge Stratus. As long as you are not losing fluid too quickly, you would be a good candidate for the BlueDevil Transmission Sealer. You should expect to see results after about 100-200 miles of driving.

      Thank you!

      -BDP

    1. Daniel-

      You should add 1 ounce of BlueDevil Transmission Sealer to every 1 quart of capacity. Most likely you will only need 1 – 2 ounces of BlueDevil to treat your gearbox. Once added you can expect to start seeing results after about 100 miles of driving.

      Thank you!

      -BDP

  9. BMW Manual Transmissions have a way for oil to get out even when all the seals are good, it’s called a breather. If the breather clogs, the transmission sprays out the oil…

  10. I have a Triumph spitfire with a j-type overdrove that is leaking. I understand that my transmission has bronze components, what can be corroded by lubricants or additive that have sulfur.

    Is your product save to use in my car?

    1. Chip-

      Yes, BlueDevil Transmission Sealer is safe to use in your Triumph. The proper amount to use is 1 ounce of BlueDevil per every 1 quart of capacity; you will not need the full bottle. Once added you can expect to start seeing results after about 100 miles of driving.

      Feel free to contact us with any questions.

      Thank you!

      -BDP

  11. I’ve got a 2000 audi tt with a bad main transmission seal leak im nervous to drive it 100 miles for a period of time is there any other way to get the treatment to work

    1. Bret-

      Once the product is added you can go on multiple short trips; it does not have to be driven 100 miles straight to gain the benefit from BlueDevil Transmission Sealer. Make sure the correct amount is added; add 1 ounce of BlueDevil per every 1 quart of capacity.

      Thank you!

      -BDP

  12. I have a 2005 ford focus manual transmission, how much should I use? During oil change I was told that my transmission is leaking.

    1. Carlo-

      Thank you for asking about your Ford Focus. You will use one ounce of the product per quart of transmission fluid in the system. Based on your capacity, you will be using about 7-8 ounces of the product. Feel free to contact our technical support line at 888-863-0426 with any other questions.

      Thank you!

      -BDP

  13. I have a ford ranger that is a 5 speed and in the last 3 week’s it made a 2 1/2 foot wide spill of transmission fluid and I was seeing if the blue devil would be ok to use on it. I don’t seem like it is a fast leak. But I’m not a mechanic so I’m not shur what a fast leak would look like

    1. Blake-

      Thank you for asking about your Ford Ranger. Based on your description, we would recommend the BlueDevil Transmission Sealer. You will be using 1 oz. of the product per quart of fluid in the system and should expect to see results after about 100-200 miles of driving.

      Thank you!

      -BDP

  14. I have a subaru impreza 2006 with manual transmission! I founded slow leak at passenger axle seal ! Will Blue devil product working on it ?

    1. Minh-

      Thank you for asking about your Subaru Impreza. As long as you are not losing transmission fluid too quickly, you would be a great candidate for the BlueDevil Transmission Sealer. It works on both automatic and manual transmissions. You should expect to see results after about 100-200 miles of driving.

      Thank you!

      -BDP

Leave a Reply

Your email address will not be published. Required fields are marked *