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Replace tranny cooler hard lines with hose?

AJMBLAZER

AJMBLAZER

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Asking this because I really have no firm knowledge of this...but think some of you guys have done it.

The Blazer has developed a new "wet spot" under it corresponding to a "wet spot" on the driver's side wheel well's front. Looks like the transmission cooler line coming out on that side is leaking.
Not a fan of those lines. In the way of everything in there, in the same space as the bolt in ORD steering brace, and generally just a pain in my ass every time I'm in there working on something.
Can I replace the line with some sort of hose or line that is flexible? I remember Zim and others talking about some high zoot hoses with fancy clamps. I figure if I spend the money to fix it I may as well solve my problems.

HOPING it's not the radiator. Supposedly it was replaced a few years ago when the previous owner had it.
 
I dont see why not. Ive got rubber lines going from the hardline to the Aux cooler and back.

I think I have it setup to go into the radiator, out of radiator into cooler and then return to trans.
 
Just wondering what kind of hose to use. I have no clue.
 
There is specific hose just for transmission coolers. Just ask for some at the parts store. I ran all rubber hose when I blew a T5 up in my IROC in college and swapped an old TH700R4 in it temporarily.

Martin
 
How would I adapt the hose to the screw on fittings on the radiator? Never worked with hose except for replacing premade units.
 
Just use a flare tool to put a slight flare on the end of one of the lines after you cut the line, or buy a barbed fitting to screw into the radiator.

Martin
 
Aj I used some red hose made by gates and got it through one of the mail orders, I'll have to look to see which one, but I used the Jegs fittings. It is 300*/250# rated hose for oil, gas, water, air applications if I recall.
There is a special fitting they have for the radiator to adapt that specific radiator thread to the pushlock fitting. I am pretty happy with the hoses, and fittings. I have probably 30-40 hours run time on them now, and no leaks or problems with them.
 
I used line I got from the local parts store, made for transmission coolers and other stuff.

I single flared hard lines and double clamped the hose clamps.

Been like that for a couple years now. I want to go back to hard lines but I don't have the whole front end exactly where I want it. They work for now so until I link the front they will stay
 
I replaced mine with steel braided line and an fittings. Not really cheap per say, but i was adding a new tranny cooler at the same time and the existing lines were all pinched and kinked.

on my old 79 longbed, I put trans fluid oil hose and doubled up fuel injection line clamps on it and it worked fine, just was a little hokey and looked temporary.
 
I think steel lines are a far more durable way to do it, that being said, i've cheated with some hoses in the past. Rated for oil for sure.

I'd think some braided stainless lines with the AN fittings is a nice way to go but not cheap either.
 
Where do you get stainless braided lines?

Zim, definitely interested in more info on yourself.
 
I've run steelbraided/AN many times....

rated rubber will be fine, just make absolutely sure your routing is chafe-free and away from exhaust...
 
Any particular clamps that would work best?

Anyone have any idea how I'd go about figuring out the size of the thread I'd need to get for barbs or what not?
 
Take the end to your local hydraulic place. I am running Parker Pushloc hose that is even rated for diesel and high pressure (it's overkill but it's cheap, about $2/ft, and I use it for pretty much everything).

I also got brass pushloc fittings (I think they're just inverted flare?) there. You're not even supposed to use hose clamps with them. They are literally impossible to remove without cutting the hose open.

Save the ends of your hardline. If you slip a short piece of vinyl over them, you can push the other end on a bottle pump and use it to flush your cooler out really well.

I went with hose a long time ago because I was afraid I'd kink the steel lines when I was trying to fix something like a fuel pump on a trail in the dark. It has worked well and if I ever damage a line, I carry a couple barb-to-barb pushloc fittings to make a splice real quick to get home.
 
I like the idea of rubber ,no rust issues or kinking or possible crushing of the steel lines that way...but I have used the steel lines mostly,except for joining an aftermarket cooler to the original lines,or a temporary quickie fix in a pinch,then I used rubber hose...it's best to use the proper rated tranny cooler /power steering return line stuff,though I've got home a few times and beyond with 5/16" fuel line hose!..fuel injection hose is better than regular fuel line,but now that stores actually keep the right stuff for tranny use in stock ,I'd go with that as first choice..it used to be few stores kept any on hand or sell it by the foot in past years..

Once I used fuel line on my trucks power steering return hose when I did a engine swap,and I didn't replace it for a long time,didn't have a bit of trouble with it..but I've had fuel line split open on a few cars I owned I patched steel tranny lines with,ones with shift kits,that must have had high enough line pressure to burst it...

I wonder if you lose some cooling by eliminating the steel lines?...I'd say its a possibility,those steel lines do get hot and radiate a lot of heat away....

I know GM advises against using copper line,but I am still tempted to go with that next time I need to replace rusted steel ones..I saw a lot of old mopars in the boneyards that had copper lines factory and they lived..maybe it was the thicker air brake rated stuff,but Dorman sells that now too!..Alumiunum isn't any good ,a friend tried a roll of that stuff and it got too brittle and cracked in short order..steel lines are probably the best,until the rust sets in....I'm surprised they dont have nylon lines like they use on gas lines yet...

Who else hates the new "snap loc" connectors they now put on cooler lines??..I much prefer good old flares and barb fittings myself..
Most GM's used 5/16" line with inverted flare ,45 degree,the threads are 1/2"x20 ..a few TH400's I had used 3/8 cooler lines,my 69 GTO had them..
 
I don't want the prebent lines. In the way. Diesel with towing package = huge radiator = lines running into and around and through all kinds of ****.
 
ya why did gm swap the coolers side to side on the 6.2 stuff and make the lines all swap around and round ? :dunno:

seems stupid to me. :popcorn:
 
All I know is the radiator drain petcock is in the worst ****ing position. I can only get to it with the tips of my fingers and tightening involves needle nose pliers and prayer.
 
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