transmission lines
Senior User
Joined: Oct 2006
Posts: 277
Likes: 0
From: The Casa
i believe they're 5/16,take a piece of the old one with you to be sure.You can buy the steel line in different lengths depending on how long you need it.Most of the time they give you two fittings to go with it.
Elder User
Joined: Apr 2003
Posts: 502
Likes: 0
If your in a bind, just get lengths of hose(rated for trans oil and pressure). I did that when I converted my drivetrain, just cut 6" of old line by the fittings, flared slightly so the hose wouldn't pop off, and clamps of course.
Kinda forgot about it, heh, its been on the truck like that for a couple of years! I have some hydraulic hose I am going to use, and an external hyd. filter for my C6.
And yep, they are 5/16"
Kinda forgot about it, heh, its been on the truck like that for a couple of years! I have some hydraulic hose I am going to use, and an external hyd. filter for my C6.
And yep, they are 5/16"
MSEE
Joined: Apr 2004
Posts: 10,386
Likes: 35
From: Austin, TX
I did the same thing as Thunderjet when I installed headers and had to reroute the lines because of interference. Bending new lines is by far one of the worst jobs ever. I used transmission oil cooler hose; they make a special type just for that. I installed barbed hose fittings in the radiator and then did the same trick that Thunderjet did to connect to the transmission. However I plan to swap to actual lines eventually, I've done this more as a quick fix. I had to slightly flare the ends of the cut-off line like he said to keep the hose from slipping. I would imagine that the flared end can wear the inside of those hose over time, which is why I would like to bend new lines eventually. But it's held up through the summer so far.
Anyway to answer the original question, most times the size is 5/16" and SAE flare but you should compare with your old line just to double check.
Anyway to answer the original question, most times the size is 5/16" and SAE flare but you should compare with your old line just to double check.
Elder User
Joined: May 2008
Posts: 672
Likes: 0
From: near Liverpool, England
just cut out the bad piece, get five-16ths hose & some clamps, I did that as a 'quick fix' on a Jeep I switched over to different engine & tranny, it worked fine, just have to tighten the hell out of the clamps 
I drive it loads after that, no leaks, btw
I drive it loads after that, no leaks, btw
MSEE
Joined: Apr 2004
Posts: 10,386
Likes: 35
From: Austin, TX
Be aware though that if you just slip hose over a smooth metal line and clamp it, the hose can eventually slip off no matter how tight you get the clamp.
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New User
Joined: Nov 2008
Posts: 13
Likes: 0
From: Charleston, SC
Oops!
I bought a 78 ford f150 with rebuilt transmission. In the first month that I drove it the tranny slipped and left me stranded in a terrible area of charleston at night! I was pissed and vulnerable. Anyway, I found a rubber hose and clamp slipped off of a smooth hard tranny line. Stupid sh!# who fixed it that way... I am now decideing to either bend my own and buy new fittings or buy the premade lines from The Bronco graveyard (55-70 dollars). Lesson learned...don't use rubber lines.
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Postmaster
Joined: Aug 2005
Posts: 2,760
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From: Gadsden Purchase
Originally Posted by fmc400
Be aware though that if you just slip hose over a smooth metal line and clamp
it, the hose can eventually slip off no matter how tight you get the clamp.
it, the hose can eventually slip off no matter how tight you get the clamp.
BTDT! :)
(but never on an automatic transmission line)
How much pressure are we talking here? :)
Alvin in AZ
Cargo Master
Joined: Dec 2006
Posts: 2,511
Likes: 8
From: hinckley ohio
5/16 brake line is what i use it comes with fittings on both ends I believe it is 1/2-20 thread for the fittings and for easier use you can get diffrent lenths to fit easier and coupler them together when i did my 78 I think I used 60 inch length. A little help is to take old line and bend new on to match.Or use a coat hanger to form your shape you need.
Posting Guru
Joined: Nov 2008
Posts: 1,647
Likes: 3
From: Halifx Pa
That happened to me years ago I had a 70 Plymouth Duster and used a rubber hydrolic line with double clamps on each end. The hole time it slowly leaked fluid, and if you tried to tighten the clamps they would fail. The lines were not flaired at the ends, which I believe would have helped them from leaking.
Bottom line, it was an anoying pain to deal with, I suggest spending the extra bucks, and avoiding the aggrivation and get it fixed right!!
Bottom line, it was an anoying pain to deal with, I suggest spending the extra bucks, and avoiding the aggrivation and get it fixed right!!
Last edited by Tees77f150; Dec 31, 2008 at 06:20 PM. Reason: spelling what else?