LML Transmission lines leaking

660catman

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May 18, 2021
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2013 Sierra 2500HD. I noticed the other day when doing an oil change I have the typical leaking transmission lines. I haven't dug into which one or more is leaking yet. Has anyone had any experience with the DRP line kit seeing it has all three lines? Would these be easier to install than the GM lines being way more flexible than OEM? For me it's a 400 dollar touch in Canadian funds.
TIA
 

JoshH

Daggum farm truck
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I'm not a fan of the full hose line kits that are out there. I like to cut the rubber section out of the factory steel lines and weld JIC spud fittings on the bare ends. You can then make your own hoses. I usually use push lock fittings and hose. If you have a leak, they're easy to replace, but I've had that setup on my LBZ for about 12 years and almost 200k miles, and they are still dry. Being in sections you can disassemble, it makes the factory lines easier to install also.
 

Dozerboy

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Jun 23, 2009
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Josh is right. I think there is even a how to on here using compression fittings. Thats what I did, because I had a hard time finding anyone that would weld them. Been on there for several years with no issues.
 
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660catman

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May 18, 2021
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I'm not a fan of the full hose line kits that are out there. I like to cut the rubber section out of the factory steel lines and weld JIC spud fittings on the bare ends. You can then make your own hoses. I usually use push lock fittings and hose. If you have a leak, they're easy to replace, but I've had that setup on my LBZ for about 12 years and almost 200k miles, and they are still dry. Being in sections you can disassemble, it makes the factory lines easier to install also.

Not a fan because of all the fittings? I’m not talented enough to weld but am willing to change them out. I just figured I’d be “upgrading” from OEM. I was also looking at the 5/8” lines as they do have 1/2” also.


2013 Sierra SLE 2500HD Crew Cab
 

Chevy1925

don't know sh!t about IFS
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bigger isnt always better. Kinda like up pipes, too big and you loose pressure and flow. there is nothing wrong with 1/2 factory stuff and no gain from going bigger other than making it hell on you to route it. i hate those full rubber hose line kits as well. they are very cumbersome and they just dont route nicely. i always wind up having to put heater hose on a section of them because they are going to rub the motor mount or somewhere i dont want them to.

id throw another set of factory ones on or do the compression fitting deal like dozer did.
 

Bdsankey

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I agree with everyone above, I personally hate the full soft line kits. DHD makes a nice kit (pricey) to replace the soft sections of line where they tend to leak or you can have fittings welded onto the lines and use push lock fittings/make AN lines like Josh did, both of which I think are far superior to the full soft hose kits.
 
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660catman

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Well I guess OEM is the way to go if I don’t fix these old ones.
Thanks to all who replied.


2013 Sierra SLE 2500HD Crew Cab
 

juddski88

Freedom Diesel
Jul 1, 2008
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I've installed countless sets of the Fleece line kit and haven't had any issues since they started using the current hose and fittings. (Since 2018 IIRC) I've also used Parker steel compression fittings and pusklok hose in some situations without any issues either. The Parker fittings are very pricey, even at wholesale, so in my honest opinion, the Fleece kit is the best value you can buy.
 
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660catman

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I've installed countless sets of the Fleece line kit and haven't had any issues since they started using the current hose and fittings. (Since 2018 IIRC) I've also used Parker steel compression fittings and pusklok hose in some situations without any issues either. The Parker fittings are very pricey, even at wholesale, so in my honest opinion, the Fleece kit is the best value you can buy.

I saw that kit too but couldn’t find a Canadian supplier and freight is a killer. Amazon.ca only listed older models up to 2010.


2013 Sierra SLE 2500HD Crew Cab
 

juddski88

Freedom Diesel
Jul 1, 2008
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I saw that kit too but couldn’t find a Canadian supplier and freight is a killer. Amazon.ca only listed older models up to 2010.


2013 Sierra SLE 2500HD Crew Cab


I've had a few kids locally try buying the Amazon version of the Fleece kit and it isn't even a close comparison on material quality. Be super careful with Amazon deals.
 
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JoshH

Daggum farm truck
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The reason I don't like the hose style kits is because I don't care for the way the hoses are sort of draped through the engine bay; I prefer the routing of the factory formed steel lines. The other thing I don't care for is how difficult it is to get leak free connections at the radiator. If they made an adapter that you could clip in the factory quick connect rather than changing the fitting on the radiator, it would be better, but I've seen the JIC adapters cause both coolant and transmission leaks because of installer error and because the fittings aren't exactly the same as factory. It's been a long time since I've installed any kits because of my dislike for them, and they may have changed since then. That's just my experience. I can buy all the hose and fittings to do all three lines for around $85 from a local Parker store. I'm sure there's a fab shop somewhere in your area that could weld or braze the fittings on your current stock lines. It's a pretty simple upgrade once that part is done.
 
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660catman

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The DRP kit I was looking at was from bcdiesel.ca. I may still go with that kit but the 1/2” version at $325.00


2013 Sierra SLE 2500HD Crew Cab