Transmission Repair (1400)

Transmission Repair


  12 Reviews

Restores performance and adds protection. This formula reduces rough shifting and friction, while eliminating slip, controlling temperature, and repairing shudder, chatter and whining. And how exactly does it do this? It reduces friction enough to prevent wear. It also helps control the temperature, while at the same time allowing some friction to prevent the internal clutch material from slipping. Hundreds of thousands of bottles sold nationally.


When adding to existing transmission fluid:

  1. Remove transmission dipstick and check fluid level. For most vehicles this is usually done while the engine is running and the transmission is in Park. The transmission dipstick is usually located near the engine oil dipstick but further back into the engine compartment. Some vehicles do not have a normal dipstick. For those, the product has to be added to the transmission through a fill plug. Consult owner’s manual for location.
  2. If fluid is low, pour entire contents of the two chamber bottle into the dipstick tube. Do NOT overfill. Tip. If necessary, to prevent overfill, drain some fluid from transmission.
  3. Check fluid level again. Top off with manufacturer’s recommended transmission fluid as needed.
  4. Replace dipstick and drive 10 to 15 minutes to circulate fluid.
  5. Depending on transmission problem, results will either be immediate or noticeable within two days or 100 miles of driving.
  6. In transmissions with seriously damaged components, a second treatment may be required. In this case, it is suggested that the transmission fluid and filter be changed and a second application of Automatic Transmission Repair be added.

When changing transmission fluid:

If using Automatic Transmission Repair when changing transmission fluid, add entire contents of bottle after filter is changed. Then refill with manufacturer’s recommended fluid to proper level. Drive vehicle and recheck fluid level.

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Stopping and preventing leaks: that’s the Bar’s Leaks specialty. Our team of top-flight chemical engineers focus on creating automatic transmission repair and other solutions that are simple to use, affordable and effective. When you choose Bar’s Leaks for solutions to automatic transmission problems and other vehicle issues, rest assured you’re getting a proven product that requires no advanced automotive expertise.

At Bar’s Leaks, we don’t just throw products on a shelf and hope they work. Our automatic transmission repair and other solutions are carefully researched and tested internally before they are introduced to the market.

Achieving the perfect product isn’t easy, but it remains our commitment when addressing automatic transmission repair. It’s a chemical technology balancing act. If you can open a bottle and open the hood of your car, you’ll be able to quickly and easily install this product.


There’s nothing more frustrating than seeing a puddle beneath your car or hearing an unusual sound coming from underneath your hood. At Bar’s Leaks, we know the kind of stress these symptoms can cause as you think about the repair cost and the inconvenience of visiting a mechanic. That’s why we offer solutions for automatic transmission repair, leaky cooling systems, head gasket, engine oil, power steering and much more. Each solution is crafted to perfectly balance effectiveness, affordability and ease-of-use. Our only desire is to see you back on the road without a significant interruption to your lifestyle and budget.

When you’re looking for automatic transmission repair, you’ll find plenty of options that claim effectiveness. But many of these solutions aren’t as effective as they claim to be, and some can even make your automatic transmission problems worse. That’s why, at Bar’s Leaks, we pour so much time, effort and energy into creating automatic transmission repair solutions that you can rely on. Made in the U.S.A., just an hour outside of Detroit, our products are time-tested, which is why we can point to tens of millions of customers served through our nearly 70-year history. When you want the best solution for your automatic transmission problems, trust Bar’s Leaks, the number one name in chemical repair solutions.

Get your Bar’s Leaks Automatic Transmission Repair today.

Customer Reviews

  12 Reviews
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 12 reviews
 by Natalie K.
Worked great

I used Bar's Leaks Automatic Transmission Repair when my transmission was giving me problems a few weeks ago and it worked great for me.  I thought I was going to have to take it to an expensive garage.  Thank you for making a wonderful product!

 by Jennifer N.
Bar's has worked for me every time

I have used the Transmission Repair as well as the Engine Repair and Cooling System Repair from Bar's Leaks and they all corrected the problems I was experiencing.

 by S. Holowach
Used Bar's Leaks for years

I have been using Bar’s Leaks for the past 50 years. It has saved me money by solving the problems without expensive repairs. In the past I have used Bar’s Leaks radiator leak sealant, the Bar’s Leaks Rear main seal repair on my Jeep which saved me a ton of money! Also, recently the transmission in my 36’ motorhome started shifting rough and I used the Bar’s Leaks Transmission repair and after just a few miles my transmission started shifting smoother and running cooler. Thank you for making products that Work! saving money on costly repairs and improving the performance of my many vehicles I have owned and still own today.

Bar's Leaks response: Thanks for being a longtime Bar's Leaks customer! We appreciate you!

 by George D.
Was skeptical, now amazed

We have used #1400 Automatic Transmission repair recently and it's truly amazing! 

Our 1995 Chevy Pickup was slipping...not anymore! Thanks! 

 by Don P.
Really helped

Bars Leaks High Mileage Transmission Repair. Trans was slipping, problem persists but not nearly as bad.

Glad we could help! Sounds like you might need further work on your transmission eventually, but glad we could keep your car on the road. Thanks for choosing Bar's Leaks, Don!

 by Brian Fisher

My 2002 F150 had trans fluid leak and slippage/shudder into overdrive. Added this and the shudder stopped almost immediately, the leak slowed and finally stopped over short period of time.

 by Bruce Hevner
Odyssey repair

I have used Lucas for a LONG time. But recently I was given an '03 Honda Odyssey. The owner is a friend. The van is not in great shape with body damage on the right side. The trans was shifting VERY badly BIG SLIP and BANG going into 3rd (the TCS and check engine light on).

The early Odyssey has a LONG reputation of trans problems (just ask Mr Google). This one had 222k on it so I immediately changed the ATF (Valvoline Max Life) along with Lucas. I saw no real improvement other than SOME reduction in whining. Still a pronounced slip & BANG going into 3rd.

After a few thousand miles I thought it would be a good idea to change it again. But THIS time I used WalMart "High Mileage" ATF and Bar's Leak Transmission Repair. The difference was surprising! After just a few miles the TCS and Check Engine light went OUT! The 2-3 shift was NOTICEABLY smoother! Still some slip but MUCH BETTER! It has now been almost 800 miles and it's still doing good!

 by John T. - Minnesota

I have just returned from SEMA where I had been speaking with the guys from the Bar's Leaks both about a problem I had had with the transmission on my wife's 2006 Escalade. I will not blame my wife as she has been taking the truck to the Lube guys religiously, however for some reason, her trans fluid had not been being checked and she had run the Transmission dry. We obviously filled it with fluid, hoping for the best, but had rough shifting and slipping.

I had used Bar's Leaks for Radiator problems many times as a young man and was always happy with the results. I asked about their "Automatic Transmission Repair" and was quite pleased with the claims they had in regards to how it would resolve my issues, however when I asked if I could purchase it near me (I am in the middle of nowhere, no stores around), there are no options. Amazingly, the reps saw my dilemma and gave me a sample pack to try.

When I got home, I followed the instructions and within a day, we could see the difference as our transmission was shifting smoother, and within 2 days, we could not even tell that we had any previous issue at all! Needless to say, we were ecstatic as in all honesty, I was expecting to be replacing an entire transmission! THANK YOU BAR'S LEAKS! You saved me a ton of money on repairs!

 by Anonymous

I used transmission additive #1400 in a 1979 F150 4wd. It was not downshifting when I stopped and hesitating on up shift when cold. Bar's Leaks 1400 and a fluid change cleared it up perfectly. I highly recommend Bar's Leaks Transmission Repair for any auto transmission before you have it rebuilt for $3000. No brainer.

 by S. M. - Dallas, TX

I drive a 1998 Ford Taurus SE. It has 136,000 miles. A few months back, I started to experience severe transmission problems. The tranny was slipping, the gears were laggy when shifting, and shifting back down through speeds was rough. I expected the worst for my car as I am in high school and can’t exactly afford a new transmission. I had already tried draining the trans. oil and replacing it, with the same problems. I was walking through AutoZone one day and noticed "Bar's Automatic Transmission Repair" on the shelf. I thought it was my best chance if any, even though I was very skeptical. After having the trans. oil drained again, and adding a bottle of Bar's, improvement was quickly and obviously noticed right off. All trans. failure signs were gone within 100 miles. I've driven the car over 3,000 miles without a single transmission problem. Truly amazing, I don’'t know how you do it, but keep it up!

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