Has anyone upgraded their hard lines to 1/2" after installing the 6.0 cooler? What fittings do you need for the lower radiator and trans? I'm guessing all 4 are 3/8" NPT but not sure.

On my '95, I replaced the 5/16" lines with 3/8" when I installed an aftermarket cooler. But didn't know if anyone had done it on the superduty?

By going to a bigger line, is 'line pressure' affected? Or is line pressure something completely different?

All thoughts and ideas welcome!!

 

I think the line pressure is in reguards to the line pressure in the valve body, not the acutal trans lines.

Thats All I had to add but ill be watching this thread for more answeres!

 

Thanks Doug.

Anybody? Anything?

 

I can't see a benefit to it. The passages in the transmission (before they are routed externally to the cooler lines) are only a certain size, and I can nearly guarantee you that they are at or below 3/8" I.D.

You won't lose pressure in the lines nor will you increase flow. The actual flow through the lines will be slower, but there will be no increase or decrease to actual volume due to the first reason listed.

 

Larger lines will flow more fluid, even if the connections at the trans are still 3/8". There is flow loss in any line, and there is more loss the smaller the line. A larger diameter line will have less loss, so there is more flow.

Line pressure is not affected by this, line pressure is a pressure inside the trans, not in the cooler lines.

 

I'm definitely not going to argue with you, Mark, as you should know. However, the greatest amount of flow is only as great as the smallest orifice will allow.

If I can relate it to Duramax performance exhaust systems.....

The outlet on the turbocharger downpipe (next to the starter)is only 2.875" I.D. The downpipe is rarely changed when a person installs a 4" (or larger) exhaust. So.......... What's the point of putting on a 4" exhaust? The most flow you'll ever get out of the exhaust is whatever can pass through that 2.875" opening. Granted, flow restriction will be reduced (friction against the ID of the pipe) with a larger exhaust due to reduced velcity.....but it will still only FLOW 2.875" worth of exhaust.

 

Whoever wrote that isn't very sharp, although he seems to contradict himself at the end. There will be less resistance to flow in a larger diameter line, which means more flow. In other words, even with a 2.875" outlet, the exhaust will flow with less back pressure though a 4" pipe than a 3.5" pipe (with non-mandrel bends as well). Same with the trans cooler lines, or fuel lines, or CCV hose. It's called fluid dynamics (yes, even a gas moving through a pipe).

Yes, you can control flow by varying orifice size, but you can do the same thing with the size of pipe it goes through after as well. Think of it as a really long orifice....

 

That's kinda what I figured about the line pressure but thought I'd ask to be safe.

That's a good way to put it Joe. "A really long orfice" Like the duramax example, our trucks would use the same principle. The outlet at the turbo is smaller than the 4" exhausts most of us run. But even though it leaves the turbo under 4"s we are still increasing the flow of the exhaust by going to 4" or larger after that.

The reason I want to do this is to lessen the restriction of the cooler lines so it's 1/2" throughout. Like most of us when we put on the 6.0 cooler, we reduced both sides creating some restriction on the return side. Although not much it's there. If you go 1/2" throughout, then your essentially opening it up more. Besides the ports on the side of the trans and the lower radiator appear to be 3/8" NPT which is very close to 1/2" anyway.

This might be something I do for my own piece of mind than for any significant benefit for the trans, but at least I'd know there wasn't any line restrictions.

 

As pointed out above, that statement is wrong.

Larger lines will flow more fluid than smaller lines, even if there is a smaller restriction somewhere in the circuit. I'm not going into all the math from my fluid dynamics course to prove it, at least partially since it's been too long since I had the course to be sure I got the math 100% right. I know I'm right on the concept, though.