Jump to content

Hose leak... transmission cooler hose???

darleyhavidson
 Share

Recommended Posts

darleyhavidson Enthusiast

darleyhavidson

Posted
Posted

Purchased a "CPO" 2022 GMC Sierra 2500HD recently and am slowly learning the ins and outs of the truck.  I found what appears to be a leaking hose covered in dirt/sludge.  It is on the passenger side and routes under the radiator.  I am assuming this is a transmission cooler hose but am not certain.  Picture attached for reference.  If it is a transmission cooler hose leaking, is this covered under the GM powertrain or bumper-to-bumper warranty?

 

dh

20260302_194002.jpg

davester Senior Enthusiast

davester

Posted
Posted

probably one of the transmission lines.  I can't say for sure, but gm likely will say it's a wear part.  they commonly need replacement for leaking at the joints where it switches between the metal tube and the rubber hoses.  But see if that crap goes all the way to the radiator or cooler up front , maybe it's the fitting that's leaking.

darleyhavidson Enthusiast

darleyhavidson

Posted
  • Author
Posted
8 hours ago, davester said:

probably one of the transmission lines.  I can't say for sure, but gm likely will say it's a wear part.  they commonly need replacement for leaking at the joints where it switches between the metal tube and the rubber hoses.  But see if that crap goes all the way to the radiator or cooler up front , maybe it's the fitting that's leaking.

I appreciate the advice, I will look it over tonight.

  • 3 weeks later...
GMCustomerService Senior Enthusiast

GMCustomerService

Posted
Posted
On 3/2/2026 at 9:11 PM, darleyhavidson said:

Purchased a "CPO" 2022 GMC Sierra 2500HD recently and am slowly learning the ins and outs of the truck.  I found what appears to be a leaking hose covered in dirt/sludge.  It is on the passenger side and routes under the radiator.  I am assuming this is a transmission cooler hose but am not certain.  Picture attached for reference.  If it is a transmission cooler hose leaking, is this covered under the GM powertrain or bumper-to-bumper warranty?

 

dh

20260302_194002.jpg

Congratulations on your recent 2022 GMC Sierra! We're so happy to have you a part of our GMC family. Please know, warranty coverage is ultimately determined by our dealers after a diagnosis is performed. We are happy to help aid in connecting you with one in your area to have this potential leaking concern addressed. If interested, simply send us an email to [email protected] that includes your forum username in the subject line. From there, we will be able to provide our most prime support. 

Another JR Senior Enthusiast

Another JR

Posted
Posted

A “CPO” truck should have a bumper to bumper warranty for the initial period of ownership. The dealer should be able to tell you if leaking transmission cooler line replacement would be covered under your warranty without any diagnosis needed. 

carkhz316 Enthusiast

carkhz316

Posted
Posted

Its either the engine oil cooler or transmission oil cooler line. Both engine lines and 1 of the trans lines go the right side (as pictured) and the other trans line goes towards the left side (if the gas engine). I can about guarantee its leaking at the crimps. I just had to replace/ repair mine last fall right after warranty expiration (of course). When I had them out, I could spin the hose around on the hard line while it was still crimped. They're just made so cheaply as the hose was also very hard like plastic. I bought new Goodyear oil cooler hose and used crimp-style AC line ferrules to rebuild mine along with a cheap hydraulic crimper. They've been fine since.

 

The dumb thing is that engine oil cooler lines are covered under powertrain warranty, but trans cooler lines are not. But, since you have the CPO b-t-b warranty still, they should be obliged to cover the trans cooler lines as well, though don't be surprised if you're met with the typical bullshit lip service where they tell you that its deemed 'acceptable seepage' and will deny the warranty claim. Then, the day after warranty is expired, suddenly it turns into a danger-critical repair that they need to perform, paid for out of your pocket of course.

  • Like 1
darleyhavidson Enthusiast

darleyhavidson

Posted
  • Author
Posted
1 hour ago, carkhz316 said:

Its either the engine oil cooler or transmission oil cooler line. Both engine lines and 1 of the trans lines go the right side (as pictured) and the other trans line goes towards the left side (if the gas engine). I can about guarantee its leaking at the crimps. I just had to replace/ repair mine last fall right after warranty expiration (of course). When I had them out, I could spin the hose around on the hard line while it was still crimped. They're just made so cheaply as the hose was also very hard like plastic. I bought new Goodyear oil cooler hose and used crimp-style AC line ferrules to rebuild mine along with a cheap hydraulic crimper. They've been fine since.

 

The dumb thing is that engine oil cooler lines are covered under powertrain warranty, but trans cooler lines are not. But, since you have the CPO b-t-b warranty still, they should be obliged to cover the trans cooler lines as well, though don't be surprised if you're met with the typical bullshit lip service where they tell you that its deemed 'acceptable seepage' and will deny the warranty claim. Then, the day after warranty is expired, suddenly it turns into a danger-critical repair that they need to perform, paid for out of your pocket of course.

 

I crawled under the truck the other day.  That hose is the engine oil cooler line.  I bought the transmission oil cooler lines thinking it was the issue.  I wrapped the engine oil cooler line in fusion tape (at the connections) to prevent any leaking or further issues.  I will give the dealership another chance to make it right, though.

 

I appreciate the feedback and sharing your experience.  I thought about changing out the engine oil cooler lines myself, but looked like quite the job of trying to route the new lines to get in place.

 

 

carkhz316 Enthusiast

carkhz316

Posted
Posted

Its not too bad if you're mechanically inclined, but you may as well utilize your warranty if you can. You deserve that privilege when they can't make stupid simple things last anymore.

  • Like 1
Another JR Senior Enthusiast

Another JR

Posted
Posted

They have been using these swaged part-hose-part-metal-tube assemblies for at least 40 years, and they have been failing at the swage after several years for just as long. My 93 K2500 has 160k miles and is on its fourth set of oil cooler hoses. They are designed for ease of factory assembly - not longevity. I do them myself, but it’s a messy, frustrating job because the quick connect fittings are difficult to disconnect in the tight access space. 

  • Like 1
carkhz316 Enthusiast

carkhz316

Posted
Posted

All my previous trucks didn't start to see cooler hose seepage until 10 years/ 150k miles on average. My current truck was dripping at half that. Thats what I'm underwhelmed by. 

 

They're actually quite easy to disconnect. Routing them out and back in a bit more work.

  • Like 1
Another JR Senior Enthusiast

Another JR

Posted
Posted
8 hours ago, carkhz316 said:

All my previous trucks didn't start to see cooler hose seepage until 10 years/ 150k miles on average. My current truck was dripping at half that. Thats what I'm underwhelmed by. 

 

They're actually quite easy to disconnect. Routing them out and back in a bit more work.

I agree they are easy to disconnect if you can get your fingers around them. On my K2500 the access is poor. 
 

I think the swage seal fails due to aging and heat damage to the flex hose material, and not mileage directly. 

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing

  • Latest Articles

  • Posts

    • Grumpy Bear
      OCI, not when but why?

      By Grumpy Bear · Posted

      https://www.msn.com/en-us/autos/news/fuel-economy-stickers-don-t-tell-the-whole-story-aaa-data-reveals-why/ar-AA26ocHk?ocid=winp2fptaskbarhover&cvid=6a4122ea3dae47e5b8dfbed5d4fd3d55&cvpid=648f6b4fc2fa4eddb4c12893aeb957ed&ei=59
    • KARNUT
      OCI, not when but why?

      By KARNUT · Posted

      What’s missing in all this is patience and investment in the future. Buy a 170K starter home. Ten years later sell it invest in a more expensive home. Eventually you’ll have a 600K home and pay starter home payments. Buy a starter car. Maintain it well. Save the payments after it’s payed for then buy an expensive car if you desire. Buy a tumbler make your own coffee, pack your lunch. Cook your own dinner. Most importantly take care of your car.
    • Atlas
      OCI, not when but why?

      By Atlas · Posted

      People mislead themselves. Statistics are highly useful indicators.   Here's the tie-in to this thread. If an oil sample tests shows a wear indicator of 7 using cheaper ACDelco oil, and a wear indicator of 2 (lower = less wear) using a particular brand of Mobil oil, and wear has a linear relationship with engine lifespan, anyone could assume that Mobil is reducing wear by more than 50% (let's just say a 200% reduction for you red state people trying hard to do math) which leads to increasing engine life by 2x. Perhaps, in a vacuum, by itself, when dreamed by AI.   Yeah?! That's what the statistic is saying, isn't it?   No, it isn't. It didn't come out and say engine life is doubled. That's a very bad assumption, and a case of severe myopia by assuming something potentially untrue about the only data point in focus.   Average cost of a new car is 50k. You bet it is.   The median cost of a new car is more like 35k. Expensive cars are skewing the perception that "average" now means a $50k price of entry for a very average automobile. And that's not true. People who don't understand statistics twist the living heck out of them to mean all sorts of things they don't actually mean.   "Average" new car payment is $1000/month. Yep, it is. And in that number are all the $35k new car buyers who bring significant equity, and the $25k new car buyers who finance the car for a month just to get a rebate, and then pay it off. Know what isn't in that number? All the payments made by people who don't finance a car.   Picking one's own data point (don't have a car payment, never paid $50k for a new vehicle, my house cost $170k, I afforded a middle class lifestyle on $4.50/hr) is just a data point. Just like earning $25/hr in an area where the median home price is almost $1 Million is a data point. In fact, it's a lot of data points given that 80% of the US population lives in/around major cities. They're not idiots; the vast majority of them do it to make a living because that's where the big money is.   The highs have become higher, lows have become lower, and how your personal mileage varies is not truth for an entire country. At the same time you can't NOT acknowledge the data. While it doesn't paint YOUR personal picture, it certainly tints the reality that you also live in, as does your single data point.    
    • ShotgunZ71
      Poll: Does your truck have the rear window leak?

      By ShotgunZ71 · Posted

      Glad you had success with it. I did as well, but about 5-6 months later it returned. Tried again, same result. This was after the dealer made several attempts and never even got it to slow down.
    • KARNUT
      Gas Prices

      By KARNUT · Posted

      3.15 Kroger’s in Montgomery Tx

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...