Just replaced my tranny @ 330K. Had a used one installed that came from a salvage yard I have used in the past. The guy I dealt with had actually driven the car a few days prior to dismantling, and said he was very confident in it. After installation, it starts off in first just fine, but slips while shifting into subsequent gears. It appears to be just fine if manually moving forward through the gears. This seems very similar to vacuum issues I have had in the past. I hate to have this tranny pulled and replaced if there is a possibility that vacuum is the culprit.

__________________
"If we can't have fun while we're here, we might as well go to the house".

1978 300CD
1985 300TD
1999 Land Rover Discovery II
rover1@sbcglobal.net

What's the vacuum level at the output of the VCV to the modulator?

Wow, Brian. Not sure my shop is equipped to check that, and I certainly don't have a clue myself.

__________________
"If we can't have fun while we're here, we might as well go to the house".

1978 300CD
1985 300TD
1999 Land Rover Discovery II
rover1@sbcglobal.net

It's relatively basic tests with a Mityvac. That's the only way to know what you've got. If the shop isn't equipped to make a basic test, they really have no clue..........

Simple test: Unplug the vacuum line going from the VCV down to the transmission modulator. If the flaring (slipping) between shifts goes away and they shifts get real hard, then you know it's a vacuum problem and nothing more.

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

OK I've not had to deal with my tranny, knock on wood, but what the heck is the VCV?

__________________
Gary
OBK #37

Vacuum control valve. Located on IP; regulates vacuum level to transmission as a function of accelerator position.

I do not want to hijack this thread but, I am having similar problems. I have a mighty vac and can check the lines. I have vacuum at the top of the BFS.
1. Does the VCV feed vacuum back to the bottom of the BFS on the VCV line?
2. Until I straighten this out. Can I remove the VCV line at the bottom of the BFS and connect it to the trans and check for vacuum at the modulator and/or make the car more driveable?
3. I'm guessing that line C (ancilliaries) is the climate control, etc. I'm sure I have leaks there, no footwell heat, just dash vents. If this is robbing vacuum from the system would capping line C at the pump help?
4. Does the pressure at the bottom of the BFS come from the manifold thru y30, the ALDA and y29? I have no manifold pressure or vacuum at idle.
Thanks.

__________________
1987 300D 146K Original #14 Head
One eye on the road, the other on the temp. gauge

Gone But Not Forgotten
1983 380 SEL Long gone
1983 300SD Wish I hadn't traded it in on a 90' Corvette
1989 300SE My all time favorite
1995 E420 Went like a bullet

What, exactly is the issue that you must straighten out?

__________________
Jimmy L.
'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John