1966 C4 tranny not moving? Reverse ok.

Hi, new member to this board.

I have a problem with my 66 289 mustang that has been sitting for several years;

No matter what I do, I can't get the car to drive forward.
Reverse engages and works GREAT.


What I've done so far:

-flush the tranny with fresh oil a few times
-used TransX additive that's supposed to free up stuck parts etc.
-flushed again a couple of times.
-overfilled the tranny in an attempt to force oil everywhere it needs to go
-removed excess oil and tried with correct amount of oil
-adjusted the Intermediate band as per the instructions in my Haynes manual:
10lbs ft, then backed the screw out 1 3/4 turns.
-tightened the screw again gradually (virtually no effect)


I have NOT tried to adjust the low/reverse band, mainly because the reverse works ok. Should I?

Big question here is, which band is being used when you start driving from standing still? I notice no difference between the two Drive positions and the Low shifter position. In Low it may creep forward even slower than in Drive, but that would be more or less standing still then.

I do not have a kickdown cable installed. It should not effect the transmission like this but I will get one asap.

I can get the car to slowly creep forward if there's absolutely no incline, and sometimes if I rev the engine REALLY high, it suddenly engages, burns rubber, and the car accelerates ok until I let off the gas. Then it disengages again, and usually won't get going again at all.


Any help welcome.

Jan Andersson
Altamonte Springs, FL

I have a hard time trusting anyone else's work, *especially* a pro.... I've seen too much

I do all my maintenance and repairs myself, have been for the past 20 years. I was a race car mechanic until last year when I moved here from Europe, I had to leave behind 2 nice garages and all of my tools.

If I knew what the problem is, I'm sure I could fix it. I just don't want to dive in and "try something" and then put it back together, only to learn that I fixed something that wasn't broken.


I am trying to learn more by surfing the net, and narrowing down the possible causes. I'm down to these:

- badly worn/damaged intermediate band (Can it be replaced without dropping
the tranny?)
-piston that controls the band (No idea if there's going to be springs and stuff flying out if I pop the cover)
-oil flow/pressure to the said piston assembly

I should have good oil pressure from the pump, since the reverse engages fine and holds tight.

As I mentioned before, I've replaced the ATF a few times, and tried to drive the car in thge meantime on a large parking lot, having to rev it up to high heavens to get any response from the transmission. The new ATF I put in, now looks noticeably darker. Burnt band?

I don't fully understand the function of the vacuum thingy near the oil pan, I think it helps shifting from 1st to 2nd and so on, but it should not prevent driving in 1st gear even if it was shot. Right?


I have a couple of months to get this thing roadworthy, but not too much time in a day to work on it. Limited budget, wife says her newly acquired Nova has higher priority



(Edit: I have ordered a Haynes transmission overhaul manual for this beast, and I am about to order a high performance intermediate band, since the consensus on the net seems to be that the C4 eats stock bands often)

Jan

Hmm... how about the clutch pack... that could be toast on mine too, right?
Would they get so bad as to not let the car move forward at all? Yet retaining normal Reverse?

Tranny book arrived today, woohoo

Jan

The vacuum line rubber hose piece felt loose, so I fiddled with it until it felt tighter.


I am probably going to pull that sucker out and rebuild it, bands and clutches and all. Got a book, found a good website with pictures and step by step procedures.

It will take time though, other cars have higher priority. Need to replace rings, hone the cyls and replace rod bearings on wife's Nova first.
No time or money to do everything right now. But dangit, I may lose my shop in June... argh. Need to get this stuff done.

Jan