Dieselsite says this on the HPX page:
*We recommend these hoses, as well as the OEM high pressure hoses, to be replaced once a year. Many chips increase the duty cycle and length of the maximum pressures of the oil pump. This places exceptional stress on the hoses that they were not intended to see from the stock programs. The pressures in this system is very commonly at 3000 psi.
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Ok, I know they are talking about the HPX and the ESOF, any others?

 

U gotta figure they're going to design in some headroom on what pressure the hoses are going to handle max. I haven't read any posts of someone who has had a HPOP line burst...just leaking crimp on rubber hosed Xline. Somebody will probably pipe in with a good story i'm sure.
Nut

 

there are talking about the lines that go from the HPOP (high pressure oil pump) to the heads. i dont know about replacing them every year but you should inspect them every so often (i take a look at them when ever i replace my fuel filter). the most common places they leak are at the ends. if you are going to do an HPX line you should look at the solid one form www.itpdiesel.com

 

Hmmmm, so how come the HPOP flex lines last nearly forever with an occational o-ring replacement.
Why can't they make them like that?

 

Ok, I'll pick up the solid hpx.
I think my esof being a pita is probably the hoses, I always step out and lock anyway. But whadd'a ya'll thing about their esof lines?
What other hi pressure lines are they talking about?

I mean geez, I'm not changing my hi press air cond line until it goes.

 

Brain fart...what's ESOF stand for??

 

The **** on the dash to shift into 4X4, Electronic Sometimes On Fly, er, I mean SHIFT on fly....

 

I didn't know the engagement of the 4x4 system relied on oil pressure. I thought it was an electroninc transfer case?

 

Dieselsite sells a replacement steel braded line for the rubber vacumm lines for the "auto" hub engagement.

 

Gotcha. Makes sense now. It has been a long day. Sorry to be off topic.

 

it is an electric transfer case with vacuum lines to operate the hubs. the lines always split and leak causing a vacuum leak and your pump to run constantly

 

It's called electrically activated, vacuum actuated.
AFAIK, it's an on-demand and your pump is running for other accessories anyway, like environmental controls.