It IS a lot less, but it can spike under the right(wrong) conditions. I have seen a very expensive 300psi gauge reduced to shards by these units. The fluid actually returns to the transmission as lubrication oil, forced under pressure through the geartrain. If it went directly back to the pan it would blow the dipstick out and blow it out the vent.

 

Pt said it was def at least 250 and that he uses line that works to 450 to be safe. I'm not sure if it runs through the rad too. Didn't check. I'd love to just be able to delete the cooler all together but idk of that's the best idea without a lot of r&d and temp monitoring. I just got off the phone with the guy from the hydro shop. He has caps coming in from Texas for the 20mm by 1.5 thread pitch of the cooler. Then he said he'd tig it together to my specified length. And that the cooler line isn't 1/2, it's 12mm. So hopefully I'll be running by Thursday night. I have no idea what'll come in as far as cost. I may still get the pt solution down the road as I like it more and need to replace my leaky lines as is. But these guys have my cooler and I asked them first. So I'll see what they can do.

 

I have a 1997 xd disco. I don't know if your's is the same tranny setup as mine, but I moved my outgoing cooler line from the cooler to the tranny to put a winch it's place. After calling the dealer, he told me the highest pressure I could expect in my cooling line was 15 to 17 psi. He said he would feel comfortable with some 7/16 trany line and hose clamps. So that is what I did. I removed about 2.5 feet of hard line and replaced it with tranny line from napa. I have not one bit of problem with it. Only the future will tell.

 

Well, on the rad with an automatic, in my 97, I've got Rotella surging through the side by the battery, just changed both those old oil cooler pressure lines, and on the side by the steering box I've got lines with tranny fluid that go in/out of rad and through that towel bar in front of the radiator. Seems like 250 - 300 would be too much even for those lines and that brass radiator coil in the side tank. Maybe that is why the replacement radiator is about $600. Seems like if it was 250 -300 all the time that we would have a lot more posts about tranny fluid leaks in that area.

 

Not sure where anyone came up with a trans cooler line running at 300psi? You'd be lucky if it hit 30psi and even that's a stretch. The cheesy crimped factory hoses are enough to tell you that there is nowhere near that kind of pressure in the system. You do realize people cut out sections of bad trans cooler line on these things and patch them with rubber hose and plain old hose clamps right? That kind of repair wouldnt last 2 seconds if it was holding back 300 psi. Anyway pressure aside your best bet would be to just pick up some bulk stainless line and bend up your own. Most stores will loan you the kit to flare and bend the lines for free. If yours are already leaky it's probably worth the effort and it wont cost a bunch, certainly cheaper than new lines. It sounds like a pain and scares most people who havent done it but it's fairly simple to make your own lines. Once you get into it and start bending you'll realize how easy it is, with the proper tools its near impossible to kink a line.

 

See attached for hose layout - spot # 5 on driver's side - the tranny fluid passes thru the radiator and the towel bar in front, and there is a sensor in the lower line which is like the overheat warning for the transmission.

 

The compression fittings pictured are rated for several factors of ten more than the steel tubing to which they are attached.

I buy the components from which they are made from a reputable hydraulic supply shop where they fab hoses for much higher pressures than we will ever see using the exact same compression fittings.

Compression fittings have gotten a bad reputation from folks using inferior brass fittings and poor installation practices.

If matched to the materials and application, they are more than appropriate.

 

Problem is less with bending the lines I think than the ****ty land rover proprietary fittings. The 20mm bump connections eyc are where it becomes hard. Not bending the lines themselves

 

Yeah pt. I had posted that before we had out conversation about compression fittings. I'm no longer afraid of them. I just don't know how suitable the whole rubber hose and hose clamp suggestion is that some guys are pushing. Id prefer a degree or two of insurance built in. Along with a little better thought out engineering. I.e the hose barbs brazed to the proper fittings. When I get the heat exchanger back from the hydro shop ill post it up and we can talk about whether the fix is suitable, over the top, insufficient etc.

 

The rubber line that I put in is protected in front of the radiator. For my application it is all land rover tubing and hose to the trany. There is nowhere the line can get caught on. In fact, it is still strapped in the same anchor spots on the rig. I left the connection on the cooler and just cut out a small portion to the hard line. Really, from what I understand, these lines run about half the pressure than a garden hose (on disco 1s) No dought the setup you are doing is going to be stonger. can't wait to see the pictures...