I was chatting with my cousin’s “friend” who is a semi-retired petroleum engineer in Rockford, IL.

I told him I was replacing the brake fluid in my 2006 CRD and he asked me what fluid I was using.
I said DOT 4.
He recommended that I check out this site: http://www.advancepetro.com/differentbrakefluid.htm
Which is where I gleaned the following assumptions.

DOT 3 : not so good (should be changed every 3 years).
DOT 5: OK for some, but you have to keep water out and realize you will have a mushy pedal. NOT good with Anti-lock brakes.
DOT 4: Good.
DOT 5.1: Better.

We went on to discuss the emergency brake line and associated maintenance.
His opinion is that the emergency brake line should be dis-assembled, inspected and lubricated every time you change your brake fluid.

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06 Liberty CRD Sport
AMSOIL
Metal Glow Plugs
Fumoto valve
Samco
PML Tran Pan
GDE Eco Tune
Euro TC
Sasquatch Provent
EGR Delete
Weeks 101 Elbow
In-tank Lift Pump
Sasquatch airbox-to-turbo hose

After looking at the service manual and what is necessary to "inspect" the manual brake cables, I think I will wait until they rust and replace them. I suspect other Jeeps are easier to service.

_________________
06 Liberty CRD Sport
AMSOIL
Metal Glow Plugs
Fumoto valve
Samco
PML Tran Pan
GDE Eco Tune
Euro TC
Sasquatch Provent
EGR Delete
Weeks 101 Elbow
In-tank Lift Pump
Sasquatch airbox-to-turbo hose