# Transmission Leaking From External Hose, New Clamps

**URL:** <https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823>\
**Category:** Maintenance/Repairs\
**Tags:** acura, tsx\
**Created:** [November 12, 2023, 10:58pm UTC](https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823 "2023-11-12T22:58:12Z")\
**Posts on this page:** 20\
**Page:** 1

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**Author:** ![YoshiMoshi3](https://avatars.discourse-cdn.com/v4/letter/y/8dc957/32.png) [@YoshiMoshi3](https://community.cartalk.com/u/YoshiMoshi3)\
**Post date:** [November 12, 2023, 10:58pm UTC](https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823/1 "2023-11-12T22:58:12Z")

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2014 Acura TSX, roughly 110k miles, 4 cylinder engine, automatic transmission.

Got the car as a used car. Noticed that it was leaking from the bottom hose attached to the external in-line transmission filter, on the filter side. See black arrow for the area I’m indicating, and yellow for the filter.

 ![image](https://global.discourse-cdn.com/cartalk/original/3X/3/1/31d9e091396a09612a17b5cdf7dab7aa7484d7ff.jpeg)  
It looked like it had been leaking for some time. Not bad enough for puddles on the floor, or enough for it register on the dipstick. It is likely seepage. The maintenance minder light came for transmission service. I figured the original clamps were “tired”, I drained and refilled it, replaced this filter, and added additional clamps. To attempt to fix this leak. In this order, for the hoses attached to the filter, on the filter end.

16 mm Spring Band Clamp | Original hose clamp | 16 mm Spring Band Clamp → Filter → 16 mm Spring Band Clamp | Original hose clamp | 16 mm Spring Band Clamp

I was not able to get any additional hose clamps on, because the length of the metal spigot on the filter was not long enough. A 15 mm Spring Band Clamp, I wasn’t able to compress it enough to make it wide enough to go over the hose. I’m pretty confident that 16 mm is the correct size. Unless of course, a imperial sized clamp is supposed to be on there, which I doubt for an Acura.

Well today I got back under the car, and it appears to still be leaking from the same spot.

 ![image](https://global.discourse-cdn.com/cartalk/original/3X/8/0/8066c60d51059aad2471c078b3607a02c82c09a4.jpeg)  
 ![image](https://global.discourse-cdn.com/cartalk/original/3X/c/5/c52161316ac89db36dd00c91ec733b247e3e51fa.jpeg)  
 ![image](https://global.discourse-cdn.com/cartalk/original/3X/2/7/2798e45ccf9061bd3ccf084a8657cadadebe9d91.jpeg)

Maybe it’s possible that when I reassembled it my hands were oily, but based on where the oil is located, it looks like a leak to me.

What is a guy supposed to do? Brand new filter and brand new multiple hose clamps. I supposed I could try a 5/8 inch spring band hose clamp. The only issue is that I can’t find a set of imperial spring band hose clamps, whose measurement is in inches and not mm that is a part of a set with various sizes. I suppose I could always try buying a bunch of 5/8 inch spring band hose clamps instead of a set. Perhaps a hose clamp between 15 mm and 16 mm would provide enough clamping force. I converted some nearby inch values to mm.

9/16 inch = 14.2875 mm - To small  
15 mm - To small  
19/32 inch = 15.0812 mm - ?  
20/32 inch = 10/16 inch = 5/8 inch = 15.875 mm - ?  
16 mm - Leaks  
21/32 inch = 16.6687 mm - To Big  
11/16 inch = 17.4625 - To Big  
6/8 inch = 3/4 inch = 19.05 mm - To big

Besides, I feel like I’m splitting hairs at this point using 15.875 mm spring band clamp over a 16 mm spring band hose clamp. The difference of .125 mm. Not to mention would have to drain and refill the transmission again to.

Thanks for any recommendations. i don’t think replacing the hose would help at all, as the hose doesn’t look damaged or elongated, resulting in the diameter being larger than it’s supposed to. This seems like a design flaw to me, but this doesn’t seem to be a common issue on this car I guess.

The previous owner went to the dealership for the past 90k miles and they never mentioned anything. Previous owner is a family member. Some Honda Acura techs online have told me the filter is not meant to be serviceable. But it’s leaking for me.

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<div class="post-metadata">

**Author:** ![Tester](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tester/32/15976_2.png) [@Tester](https://community.cartalk.com/u/Tester)\
**Post date:** [November 12, 2023, 11:05pm UTC](https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823/2 "2023-11-12T23:05:39Z")

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Try replacing the hose.

Tester

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<div class="post-metadata">

**Author:** ![YoshiMoshi3](https://avatars.discourse-cdn.com/v4/letter/y/8dc957/32.png) [@YoshiMoshi3](https://community.cartalk.com/u/YoshiMoshi3)\
**Post date:** [November 12, 2023, 11:40pm UTC](https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823/3 "2023-11-12T23:40:43Z")

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Thanks. Not sure the pressure rating of the hose or the inner or outer diameter or length. I suppose I should just avoid the hassle and get the OEM hose?

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**Author:** ![old\_mopar\_guy](https://avatars.discourse-cdn.com/v4/letter/o/6bbea6/32.png) [@old\_mopar\_guy](https://community.cartalk.com/u/old_mopar_guy)\
**Post date:** [November 13, 2023, 12:29am UTC](https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823/4 "2023-11-13T00:29:53Z")

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Just get a hose from the dealer and use worm drive clamps. I hate spring clamps.

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<div class="post-metadata">

**Author:** ![Tester](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tester/32/15976_2.png) [@Tester](https://community.cartalk.com/u/Tester)\
**Post date:** [November 13, 2023, 12:51am UTC](https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823/5 "2023-11-13T00:51:16Z")

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It looks like you can use just regular fuel line hose from any parts store.

I stopped using worm drive clamps years ago.

[![](https://global.discourse-cdn.com/cartalk/original/3X/3/7/37321339b91f4c47c93dde4ef6577467364757a9.jpeg "MotorWeek | Goss' Garage: Clamps & Hoses") ](https://www.youtube.com/watch?v=FhvYnQefmig)

Tester

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<div class="post-metadata">

**Author:** ![YoshiMoshi3](https://avatars.discourse-cdn.com/v4/letter/y/8dc957/32.png) [@YoshiMoshi3](https://community.cartalk.com/u/YoshiMoshi3)\
**Post date:** [November 13, 2023, 2:56am UTC](https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823/6 "2023-11-13T02:56:22Z")

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Do you guys think it’s likely a 3/8 inch fuel hose, based on me using a 16 mm clamp on it? If the fuel hose I purchase has a stated pressure rating, what should I look for and what should I stay away from?

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**Author:** ![davesmopar](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/davesmopar/32/41750_2.png) [@davesmopar](https://community.cartalk.com/u/davesmopar)\
**Post date:** [November 13, 2023, 3:45am UTC](https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823/7 "2023-11-13T03:45:51Z")

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You don’t measure them by the OD, find the open end wrench that fits the tightest on the OD of the base metal line and that is the ID of the transmission hose you need, then use a worm clamp to tighten the hoses in place or spring clamp, either work, not that hard…

Most transmission cooler lines are 5/16, these newer cars could be anything… lol

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**Author:** ![Nevada\_545](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/nevada_545/32/41232_2.png) [@Nevada\_545](https://community.cartalk.com/u/Nevada_545)\
**Post date:** [November 13, 2023, 5:38am UTC](https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823/8 "2023-11-13T05:38:47Z")

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> [@YoshiMoshi3](#):
>
> This seems like a design flaw to me

The hoses lasted 10 years, replace them.

It is best to have all the replacement parts before replacing the filter, avoids wasting a lot of time measuring and checking pressure ratings.

 ![image](https://global.discourse-cdn.com/cartalk/original/3X/2/a/2a2b922998db632a860a02a179501c7aa3d5cc58.png)

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<div class="post-metadata">

**Author:** ![oldtimer-11](https://avatars.discourse-cdn.com/v4/letter/o/e79b87/32.png) [@oldtimer-11](https://community.cartalk.com/u/oldtimer-11)\
**Post date:** [November 13, 2023, 7:29am UTC](https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823/9 "2023-11-13T07:29:09Z")

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Most professionak mechanics recommend spring clamps, I have always preferred worm drive ones and have never had any problem with them.

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<div class="post-metadata">

**Author:** ![mdixter](https://avatars.discourse-cdn.com/v4/letter/m/e36b37/32.png) [@mdixter](https://community.cartalk.com/u/mdixter)\
**Post date:** [November 13, 2023, 10:31pm UTC](https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823/10 "2023-11-13T22:31:28Z")

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My dad preferred worm drive clamps, so so did I, until the lower radiator clamp on a past Honda kept loosening itself. Changed it back to the OEM spring clamp and never looked back. Maybe it was a cheap clamp, but one of the reasons spring clamps are preferred is that they are considered to be temperature compensating.

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<div class="post-metadata">

**Author:** ![YoshiMoshi3](https://avatars.discourse-cdn.com/v4/letter/y/8dc957/32.png) [@YoshiMoshi3](https://community.cartalk.com/u/YoshiMoshi3)\
**Post date:** [November 19, 2023, 4:04pm UTC](https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823/11 "2023-11-19T16:04:20Z")

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I decided to cave in and buy the official hose to avoid having to worry about pressure ratings. Looked into getting generic fuel hose, but they were all rated to different pressures. Did not want to have to replace it again.

Anyone know fuel hose markings?  
It seems to be  
“TAS NOH-F 3402”. I tried to Google the manufacturer TAS, but couldn’t find anything. Also couldn’t find out what NOH-F means or 3402.

 ![image](https://global.discourse-cdn.com/cartalk/original/3X/5/c/5c08c2ea99180dc8bd4ab041a09d7290d0c23bbb.jpeg)  
Part number 25213-RTA-007  
 ![image](https://global.discourse-cdn.com/cartalk/original/3X/e/c/ecd8e0b43b8ffb502181ce63390f866f23c080e1.jpeg)  
Googling the part number shows that it’s a “Hose (175MM) (ATf)”  
 ![image](https://global.discourse-cdn.com/cartalk/original/3X/1/a/1a60362818f2ea52b3833dc8d8f99b5146c79635.jpeg)  
Outer diameter is approximately 17 mm or about 0.669291 inches  
 ![image](https://global.discourse-cdn.com/cartalk/original/3X/1/8/1825826ee77f1f1835c3d32bff95c0819be9005e.jpeg)  
Inner dimeter approximately 5 mm or about 0.19685 inches

So very interesting indeed. Seems to be a non-standard size. Converter some nearby values

2/16 in = 1/8 in = 0.125 in = 3.175 mm  
24/128 in = 12/64 in = 6/32 in = 3/16 in = 0.1875 in = 4.7625 mm  
**25/128 in = 0.1953125 in = 4.96094 mm**  
26/128 in = 13/64 in = 0.203125 in = 5.15937 mm  
14/64 in = 7/32 in = 0.21875 in = 5.55625 mm  
8/32 in = 4/16 in = 2/8 in = 1/4 in = 0.25 in = 6.35 mm  
3/8 in = 0.375 in = 9.525 mm  
4/8 in = 1/2 in = 0.5 in = 12.7 mm  
20/32 in = 10/16 in = 5/8 in = 0.625 in = 15.875 mm  
84/128 in = 42/64 in = 21/32 in = 0.65625 in = 16.6687 mm  
85/128 in = 0.6640625 in = 16.8672 mm  
**86/128 in = 43/64 in = 0.671875 in = 17.0656 mm**  
44/64 in = 22/32 in = 11/16 in = 0.6875 in = 17.4625 mm  
12/16 in = 6/8 in = 3/4 in = 0.75 in = 19.05 mm

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<div class="post-metadata">

**Author:** ![old\_mopar\_guy](https://avatars.discourse-cdn.com/v4/letter/o/6bbea6/32.png) [@old\_mopar\_guy](https://community.cartalk.com/u/old_mopar_guy)\
**Post date:** [November 20, 2023, 11:52pm UTC](https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823/12 "2023-11-20T23:52:24Z")

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Typical pressure in the trans cooler line is 5-10 psi. You could blow into it harder than that.

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<div class="post-metadata">

**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\
**Post date:** [November 21, 2023, 9:53pm UTC](https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823/13 "2023-11-21T21:53:22Z")

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That’s interesting. I’ve always thought the trans cooling line pressures was considerably higher.

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<div class="post-metadata">

**Author:** ![YoshiMoshi3](https://avatars.discourse-cdn.com/v4/letter/y/8dc957/32.png) [@YoshiMoshi3](https://community.cartalk.com/u/YoshiMoshi3)\
**Post date:** [November 22, 2023, 2:19am UTC](https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823/14 "2023-11-22T02:19:39Z")

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Hey thanks. I think you are probably right about it not being high pressure.

What about the sizes though? It seems like an oddball size of 5.0 mm inner and 17.0 mm outer.

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<div class="post-metadata">

**Author:** ![old\_mopar\_guy](https://avatars.discourse-cdn.com/v4/letter/o/6bbea6/32.png) [@old\_mopar\_guy](https://community.cartalk.com/u/old_mopar_guy)\
**Post date:** [November 22, 2023, 2:45am UTC](https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823/15 "2023-11-22T02:45:47Z")

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Who knows? The only dimension you need to be concerned with is the inside dimension.

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<div class="post-metadata">

**Author:** ![YoshiMoshi3](https://avatars.discourse-cdn.com/v4/letter/y/8dc957/32.png) [@YoshiMoshi3](https://community.cartalk.com/u/YoshiMoshi3)\
**Post date:** [December 25, 2023, 5:04am UTC](https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823/16 "2023-12-25T05:04:32Z")

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So I did end up replacing the hose, and got two brand new OEM hose clamps. Drove it for a few weeks, and the leak seems to have stopped. Thanks everyone.

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<div class="post-metadata">

**Author:** ![YoshiMoshi3](https://avatars.discourse-cdn.com/v4/letter/y/8dc957/32.png) [@YoshiMoshi3](https://community.cartalk.com/u/YoshiMoshi3)\
**Post date:** [February 11, 2024, 2:42am UTC](https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823/17 "2024-02-11T02:42:21Z")

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So after replacing the hose, and two hose clamps on the filter, with OEM parts, I still have a leak in this area, but it appears to no longer be from the filter area.

 ![image](https://global.discourse-cdn.com/cartalk/original/3X/5/9/596ae54a3b93f0ea35e9fc8745aa81fd439b5e58.jpeg)  
 ![image](https://global.discourse-cdn.com/cartalk/original/3X/3/0/309df0c81ff8f7aa5244968703b518a01a91447f.jpeg)  
 ![image](https://global.discourse-cdn.com/cartalk/original/3X/b/7/b7e6f83e9e3ad59f871c692b7fd0a2470d5975af.jpeg)

I tried cleaning it up as much as I could so that way I can get a better idea of where it is coming from and know for certain.

I did notice that it is very wet and shiny looking in the area where the axle enters the transmission.

 ![image](https://global.discourse-cdn.com/cartalk/original/3X/2/b/2bb3d9f099c269aa108e4791204e125c9d7e131e.jpeg)  
Could it be that the oil seal is leaking on me?

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<div class="post-metadata">

**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\
**Post date:** [February 11, 2024, 9:34pm UTC](https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823/18 "2024-02-11T21:34:00Z")

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No idea what’s causing your tsx leak, but I occasionally notice a little trans fluid on the top of my Corolla’s M5 manual trans, which I believe is coming through the vent. Any fluid on top will eventually find its way to the bottom of the trans.

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<div class="post-metadata">

**Author:** ![YoshiMoshi3](https://avatars.discourse-cdn.com/v4/letter/y/8dc957/32.png) [@YoshiMoshi3](https://community.cartalk.com/u/YoshiMoshi3)\
**Post date:** [February 12, 2024, 12:41am UTC](https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823/19 "2024-02-12T00:41:13Z")

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Yea thanks, is it possible to replace the oil seal, by removing the CV axle to gain access to it, and then remove it from the outside of the transmission, or you have to disassemble part of the transmission to replace it?

At some point in the near future I might remove the axle to take a peak, but that is what I’m suspecting the leak is coming from.

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<div class="post-metadata">

**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:** [February 12, 2024, 2:23am UTC](https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823/20 "2024-02-12T02:23:35Z")

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> [@YoshiMoshi3](#):
>
> At some point in the near future I might remove the axle to take a peak, but that is what I’m suspecting the leak is coming from.

Is it worth replacing the seal?

Is it dripping or just seeping?

[Next page](https://community.cartalk.com/t/transmission-leaking-from-external-hose-new-clamps/193823.md?page=2)
