Technical Transmission issues

Lost third gear in the C-4 thats in my sunliner while in Florida,noticed the Lokar kickdown cable came out of the endof the attaching bracket on the carb and looks to have been trying to engage the passing gear on the trip down so could that have been the cause of wiping out the clutches for third which I presume happened since there is nothing when it goes in third. I was hoping it was vacumn related but with black residue on the dipstick and the fluid is grity there is something serious going on.

 

does reverse still work?

 

Reverse,first and second are still good.

 

Jeff did you make it home?

 

I had to rent a truck and trailer and hauled it home,third went completely out after I left the show sunday.

 

Can't see how you're getting reverse here, with the direct clutch blown out

 

I was told third was controlled by clutches so if those clutches work other gears what would cause just third to go,there is some black residue in the fluid so clutch or band.

 

You sure rev. works? You backed it off the trailer when you got home?
In that case , I don't know,..but you'll know soon enough after it's torn down.

 

Reverse works just as good as first and second.

 

it's been a long long time, but I seem to recall that there are two clutch packs in a C4, both are engaged in 3rd. One of them is used for all Forward gears. The other is engaged only in 3rd gear, and Reverse. So...if First and Second work, the Forward clutch is working. If Reverse works, the 3rd/Reverse clutch is working. It seems odd that 3rd is not working, under these circumstances!

I'm just trying to explain Mark's confusion

 

Have you freed up the kickdown cable and made sure the linkage and valve body aren't still seeing a passing gear condition? Are you using an aftermarket shifter of some sort? Is the shifter adjusted properly so that when the indicator shows "Drive" the manual valve in the trans is truly in the Drive position?

 

Been a looong time for me too......1976, but I did one and seem to recall there is a band in there too...used when reversing ......

 

Reverse and low use a band. 2nd uses a different band.

 

Can't be a band . If you have reverse, the rear band works. Also used for engine braking in manual lo. If you have second, the front band is holding the direct drum.
This all academic anyway..Needs to come out.

 

Reverse does use a boost system , where drive doesn't , so it's conceivable you might have enough pressure to engage the direct clutch for reverse. In that case , you could have a valve body issue. But, if you have debris in the pan, it's got to come apart anyway.

 

I was talking to a trans shop and was told about the 2-3 shift valve in the valve body so I am going to drop the pan and install a valve body from another trans I have and look for debris. This happened suddenly with no warning.

 

Lokar kickdown cable and is not binding and working like it should,original shifter to the car and pointing to where it should.

 

Time for an AOD!

 

Thinking about that but need to drop the pan first and try to see what went wrong.

 

Jeff, Are you saying it freewheels in 3rd, or it won't go into third (stays in second?)

 

It does not stay in second,its like it shifts into neutral. When it first started acting up it would stay in second and I would have to let off gas to go into third.

 

Is the vacuum hose still on the modulator valve? I had one come off once, only way to get it into high was hold it wide open and it would finally shift.

 

I am going to pull it in the big garage and get it up off the ground tomorrow and check.

 

See above...
"It does not stay in second,its like it shifts into neutral."

 

That's what mine would do if you didn't stay in it. Shift normal 1-2, then if you didn't floor it, it would act like it was in neutral. Floor it and hold it, it would finally shift into D. But mine did slip some too, so it might not have been the total cause. Hell, that was about 40 years ago, sometimes I don't remember what I ate today!

 

I hope its simple but I spent a bunch of money hauling it home.

 

I hope so, too, 'casue otherwise you may have found a brand new failure mode.

 

Getting vacumn and installed modulator from the extra trans and still the same,I can get it into third by letting off the gas but its not that noticable. It did go into freewheeling in third when I was down south but could not get it to do it while on the stands,fluid is still red but does not smell right so its coming back off the stands and up to the car wash to clean the road grime off it and will cover it up in the small garage and deal with it in the spring but might try to find another trans or have the extra trans rebuilt. Not sure I want to waste money on fluid and gasket to change the valve body due to the funny smelling fluid so I think its a internal problem.

 

Does it smell burned? Some people say like burned toast, just a burned smell to me.

 

The fluid is still red but starting to smell burnt and a little gritty.