[mercury.marcel]

Hello everyone,

I am not sure where I should introduce myself, but I am completely new to this forum.
My name is Marcel Moret, I imported a original blackplate cougar from california december 2009. Driving it is so much fun, there are very few american classics on the roads here, especially early model cougars are very rare in The Netherlands. People seem to be always interested and intriged with the "remmington-grill" hide-away lights.

I have been strugling with a question regarding my automatic transmission.
There is currently a later model engine (71 302) in my 67 cougar and I think the transmission is a 71 as well. its a standard dual range c4 as far as my knowledge stretches.

When I drive normally, everything is well, responsive trothle, kickdown and accelration seem to be normal.

However, when I slow down and the transmission shifts back to first gear, there is a rather loud metal-sounding-clunk, you can also feel the hasher downshift.
This is only when it is in regular drive, D. when I switch to "sport-mode" or "2" there's no sound or hash down shift.

Could this be due to a faulty valve or something? I have checked the transmission fluid level and it apears to be correct (it's very hard to see the hot transmission fluid on the dipstick, because it's so thin)

 

[Cedar Rapids Ia]

See if the vacuum modulator hose has popped off (or leaking air)...it could be the valve too I guess..... Just guessing on this one, but it is a place to start. The Netherlands!?! Holy crap! It never ceases to amaze me how many people around the world love these classic Cougars! One last thought...what type of transmission fluid are you using??? Someone correct me if I am wrong, but it should be red in color, right?

Best regards
Jay

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How To Service Ford Mustang C4 Transmissions
<TABLE cellSpacing=0 cellPadding=0 itxtHarvested="0" itxtNodeId="26"><TBODY itxtHarvested="0" itxtNodeId="27"><TR itxtHarvested="0" itxtNodeId="28"><TD vAlign=top itxtHarvested="0" itxtNodeId="30">This is the vacuum modulator, which either screws in or is retained with a clamp depending the C4's vintage. To adjust the vacuum modulator, which controls shift points, remove the vacuum hose and use a small common screwdriver to make adjustments clockwise or counterclockwise, but never more than one-quarter turn at a time. Never go more than four turns in either direction. Clockwise, you increase diaphragm spring pressure, which delays upshifts and makes them firm. Counterclockwise makes shifts softer and earlier. Check the vacuum hose for leaks, which can cause both engine and transmission performance issues. View Related Article </TD></TR></TBODY></TABLE>​

Read more: http://www.mustangmonthly.com/techa..._c4_transmissions/photo_18.html#ixzz1kVMceMJQ​

 

[Bad69cat]

Yes sir - it should be a pinkish fluid - but is hard to see if it's new/clean. You shold have a fairly noticable downshift when you step on the throttle - the modulator controls that via the engine vacuum. The clank you hear could simply be a driveshaft Universal joint that has bad bearings in it.....sometimes you will hear a similar clank when you first put it in gear too if it's bad. It's easier to check it by removing the driveshaft and looking at it. It'll be obvious.

 

[woodsnake]

+1 for checking the driveshaft/ U (Universal) joint.