NEW owner 1991 f250 need help.
 

Hello all, my name is Jonathan and I need some help find a transmission trans cooler line. 1991 F250 with 5.8. Any ideas

If you can, check with a local NAPA store .They usually carry the tubing size you need and you can purchase the length you require very possibly all made up.
If it is a little long you might place a slight bend in the line to accommodate the increased length. Otherwise you might need to use 2 pieces or cut to fit . Then you will need to use a tubing flaring tool.

Thank you for getting back to me, I've tried ever connection I have and nobody has it in stock. So thank you for confirming my thoughts on just making it myself.

Tubing made to exact fit is pretty difficult to find.
Most times the person has to make their own lines and most folks don't posses the tools to do the job.A good shop would have the tools.

If it's just a section that is bad, cut out with a tubing cutter, add a new section and join it together with compression fittings. I have done it many times.

Thank you, thats what I'm going to do because I have looked everywhere. Thanks again.

You might want to check as to why flared fittings are recommended for brake lines.

The pressure in the cooler lines is no where near the pressure of which is in brake lines. There's no need to flare the lines if a new section is spliced in. Compression fittings are more than adequate.I have seen some Chrysler vehicles which used a formed oil resistant, reinforced rubber line from the factory.

Before assuming anything, you might want to check what kind of pressure is in those lines.

If possible , when I suggest a procedure , I will try to provide a good reason for doing so.
Regarding the pressure in the trans cooler lines, Why is it you rarely hear of coolant getting to the trans when the trans cooler develops a problem?
The reason is the pressure in the trans cooler lines is much higher than the cooling system pressure and it is more common for trans fluid to get into the cooling system.

Just because we got away with a shortcut a few times does not make it right.

The pressure in the cooling system is around 16 LBS. The cooler lines are a little higher than that. Not high pressure where a compression fitting would not work for a transmission cooler line.High pressure would blow out the light weight cooler in the radiator. I have done it on my own vehicles and never had a leak.That is no way as high as can be seen in the braking system. I have seen where mechanics have used neoprene tubing onto a flared end with hose clamps as a repair for the cooler lines. I don't recommend that but was surprised that it worked and didn't blow out. Go look on Haydens web site. Their external transmission coolers use reinforced hose sililiar to fuel injection hose but oil resistant..