FE C6 transmission

[blue68]

Okay.. I have a 1969 Ford C6 transmission backed up to my FE. It's got all new seals, new modulator valve, new vaccum lines, and new flywheel, and of course new oil.

When driving down the road, it only changes gears ONE time! This occurs at 35mph. So I only have a 2 speed automatic Does anyone know whats wrong with my transmission? I think all C6's are 3 speeds, right?

[spartman]

The C6 is a 3 speed tranny.

The first shift should occur at about 10-20 mph.

Might be a really soft shift and you don't notice it.

Do you have a tach on your truck?

That way you could see when it shifts.

[blue68]

There's no tach on the truck. I really think there is no third gear. If there is, then it is soooo soft that even a tach wouldnt pick it up. 2nd gear jerks really hard. And you're right, it does occur at 10-20 mph, but it occurs at 35 when you start off fast (which I shouldnt be doing on a new motor anyways). It's like a 2 speed power glide right now. My brother has a 351M in his '79, with a C6, and you can actually feel and hear third gear. On my truck you cant feel or hear it. It has no juice after 40 mph, which is another symptom of no third gear, I guess?? Anybody know whats wrong?

[spartman]

Might want to get a tranny book and look up the procedures for adjusting the bands on it.

[Maxum96]

Okay.. I have a 1969 Ford C6 transmission backed up to my FE. It's got all new seals, new modulator valve, new vaccum lines, and new flywheel, and of course new oil.

When driving down the road, it only changes gears ONE time! This occurs at 35mph. So I only have a 2 speed automatic Does anyone know whats wrong with my transmission? I think all C6's are 3 speeds, right?

Your transmission might be misadjusted and it's doing the 1-2 and 2-3 shifts at the same time. I've had that happen before.

[ToughOldFord]

If his engine's starting to top out at 40 then he's not getting into third.
Check that you have vacuum at the modulator, a strong one too, from the intake, not the carb. Check that your linkage is adjusted correctly so that you're actually shifting into third. My own truck is off, drive is in the "N" selection so if I have it in "D" i'll actually be in 2ond.

[blue68]

What are bands? Do I have to go in my transmission to do this?

[spartman]

The bands adjust from the outside.

I would recommend to get a tranny book or go to your local library and see if they have Mitchell Manuals for your truck.

Then read up on the procedure and also try the other guys suggestions too.

[blue68]

Alrighty. Thanks!

[spartman]

Just let us know what you find out.

[blue68]

Well, I've done some investigation, and my bands are set correctly. The problem is my kickdown rod. It's evidently misadjusted or something, and thats keeping it out of third. I think the adjustment is off at the trans, but I need to check

[spartman]

simple check for that is to just unhook it and see if it shifts then.

Won't cause any problems if you do it.

[blue68]

I just did the weirdest thing.. to test my tranny. I unhooked the kickdown, like you said. It did the same thing its always done. No difference. But then, I came to a complete stop in the road. I put it in 1st gear manually, accelerated, and shifted to 2nd manually, accelerated, and put it in "D" (3rd) manually. All gears were there, and you could hear and feel them all. But when you just put it in "D" and take off, just the 1st and 2nd ones are there. Strange, Huh?

[ToughOldFord]

That's pretty much the symptoms of a bad modulator. I had to shift mine manually into 3rd when I first got it.

[spartman]

To find if you have a bad modulator pull the vacum line off of it, if you see tranny fluid in the line then the modulator is bad.

I would get a replacement anyway TOF is spot on