Anything special I have to do to pressure test a #4?
Am I going to lose pressure thru the expansion bottle? The cap is tight. What psi should I be shooting for?

Well neither drive would hold pressure for very long. All I did was add spacers, they were great last year so I don`t suspect a problem but just not sure where the pressure is going.

I used my HVAC leak solution and could not find any leaks.

Hey Dan, on those drives, there is a doohickey that when the drive is bolted on, it makes the connection to the reservoir, so fluid can flow back and forth. The reservoirs should be vented, and that's probably where your pressure bled off. Im no drive guy but I think you'd need to cap off the reservoir or plug the line going to the reservoir, for a accurate test

Yeah that was my question, oh well I'm impatient and now the drive is full of oil. So we'll see.