I've got a 300CD with a few vaccum problems, hard shifting, etc.

The vacuum valves in the doors, fuel door, 5 servos (behind the console) and starter switch were all replaced, and most of the problems are fixed.

However, I've still got:

Hard shifts. The brake booster line has a broken nipple leading to the tranny; replacement of this may take care of the hard shifts (or not?)

No heat to the floorboards. Checked the vaccum from the servos, and zip, nada, nothing in any setting coming out of the hoses or diaphragms. Since they're both (passenger and driver side vents) non operational, the CCU may be at fault, or so my dealer suggests (then again, why wouldn't he, at nearly $400 bucks installed!).

I've got very little patience for chasing down vaccum leaks, but installing a new CCU is so simple a monkey could do it.

Would replacing the CCU have any bearing at all on the floor vents? The electronics are quite primative, leading me to wonder how often this part fails. Is there anyone who rebuilds these Carter-era electronic wonders? I noticed there is a core charge from people who sell new units.

Also, I have the typical "no heat in the center vents" situation, though some in this forum say it's normal (MB designed) not to have heat come from those vents.

The fan and temp settings work ok. AC is out, but that's for another reason.

Occasionally, the little buttons used to jump ship when one was pressed, but I took care of that with some clips used inside the unit.

Basically, I'd hate to blow a serious chunk of change on one of these for no reason. Any ideas out there?

Thanks

Gil