Proper valve stem length is really a function of wheel covers or the lack of. If not using any wheel covers you normally want the shortest stems available especially for driving in snow or any off road adventure. The longer the stem the easier it is to break off.  With covers you want the valve long enough so it can be serviced with the wheel cover in place. 

In the real truck world metal valves are usually used. 
The 65 psi is the max inflation pressure for the tire. You want to follow the door jamb specifications or get the load-inflation table for the tire you are using and use the maximum axle weights to determine proper pressures.

Dennis 

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of T Collins
Sent: Thursday, August 20, 2015 12:37 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Proper Tire valve stems?

Hello List,

I'm about to get all new tires mounted. I know these are LT tires and are rated @65psi. When replacing the valve stems is there any that "NEED" to be used because of the higher PSI.

I dont want a leaky tire with these​. I have the 14" steel wheels. Also I think the current stems are too short. Should they be 2" valve stems?

What says you?

Thanks,
T.