Author Topic: Trans not downshifting when slowing down/rolling through stops  (Read 4354 times)

Offline MyMopar

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Trans not downshifting when slowing down/rolling through stops
« on: August 27, 2008 - 10:02:05 AM »
Aside from having a vibration at highway speeds I have a second problem.  This being the transmission kickdown.  I have the Bouchillion trans kickdown cable kit and it worked perfectly on the old trans.
Problem now is this new trans doesn't seem to respond to it when slowing down.  I have it properly set as per the direction.
Here is how it is behaving:
Put into D and go, it shifts 1-2 very nice and firm then it shifts 2-3 at a higher RPM than the 1-2 shift but it does shift.  Sometimes depending on the throttle use, 1-2 shift chirps hard and can go up in smoke and the 2-3 shift chirps hard and the rear breaks loose sometimes too, depending on the throttle of course.

So the problem is when slowing down for a corner or yield, it stays in 3rd gear and never downshifts, ever.  It will only go back into first gear by itself if I come to a complete stop.

It is a brand new rebuilt trans, new converter, new driveshaft, near new rear 3.23 gear suregrip.  I checked the fluid in neutral running hot and it was 1 quart low, added a quart and it reads perfect.  Took it for a drive again and still the same problem, it just won't downshift into 2nd gear on its own when going slow or rolling through a stop or similar.
It will downshift into 2nd or 1st gear when the throttle is to the floor.  Is this a problem or hurting the trans or is it something I just live with.  The car runs fine but taking off from 10 mph in in 3rd gear worries me.
1969 (OO===]|[===OO)
1973 (OO/=====\OO) <---SOLD
1997 (O|||||O) <---SOLD

Smoke tires, not drugs!




Offline FJ5_440

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Re: Trans not downshifting when slowing down/rolling through stops
« Reply #1 on: August 27, 2008 - 10:29:05 AM »
Make sure the kickdown is returning when the throttle does.  I accidentally left the return spring off of mine once, and it acted kind of like your description.
** Shane **

Offline MyMopar

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Re: Trans not downshifting when slowing down/rolling through stops
« Reply #2 on: August 27, 2008 - 10:38:26 AM »
Make sure the kickdown is returning when the throttle does.  I accidentally left the return spring off of mine once, and it acted kind of like your description.
Good suggestion, I'll double check but with the cable set-up it seems to spring back when I manipulate it by hand.  Worth verifing with a person in the car using the pedal, I doubt it will be this simple though  :(
1969 (OO===]|[===OO)
1973 (OO/=====\OO) <---SOLD
1997 (O|||||O) <---SOLD

Smoke tires, not drugs!

Offline tactransman

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Re: Trans not downshifting when slowing down/rolling through stops
« Reply #3 on: August 28, 2008 - 03:46:51 PM »
My guess would be if you have a completely different trans,VB and all,that you have one in the car now that does not have the part throttle kick down on the VB.
Terry-tactransman 
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Give a man a fish and he eats for a day,teach him to fish and he eats for a lifetime.

Offline MyMopar

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Re: Trans not downshifting when slowing down/rolling through stops
« Reply #4 on: August 29, 2008 - 09:39:56 AM »
My guess would be if you have a completely different trans,VB and all,that you have one in the car now that does not have the part throttle kick down on the VB.
Ok I am trying really hard to think what VB stands for but I can't figure it out.  Are you referring to the valve body?
Now I am no tranmission guy by any means but if you are reffering to the valve body why would some allow part throttle kickdown and others not?  That seems very odd.  Is there any fix for this?  It isn't a huge deal but I don't want to burn up the transmission.
1969 (OO===]|[===OO)
1973 (OO/=====\OO) <---SOLD
1997 (O|||||O) <---SOLD

Smoke tires, not drugs!

Offline tactransman

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Re: Trans not downshifting when slowing down/rolling through stops
« Reply #5 on: August 29, 2008 - 11:16:52 AM »
Sorry,yes, VB is valve body.Give me the story on why you have a different trans in it now. Did the original one get rebuilt or a whole different trans is in it now? Earlier transmissions did not have a VB with part throttle kickdown part on them.
Terry-tactransman 
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Union, Mo.
Give a man a fish and he eats for a day,teach him to fish and he eats for a lifetime.

Offline ChallengerHK

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Re: Trans not downshifting when slowing down/rolling through stops
« Reply #6 on: August 29, 2008 - 11:37:40 AM »
Is there a way to tell by dropping the pan, i.e. without pulling the valve body to inspect it?


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Offline tactransman

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Re: Trans not downshifting when slowing down/rolling through stops
« Reply #7 on: August 29, 2008 - 11:50:44 AM »


I am not for sure that is what is going on here in MyMopar's situation but here is a pic:

Terry-tactransman 
Torqueflite/Automatic Transmission Specialist
Union, Mo.
Give a man a fish and he eats for a day,teach him to fish and he eats for a lifetime.

Offline ChallengerHK

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Re: Trans not downshifting when slowing down/rolling through stops
« Reply #8 on: August 29, 2008 - 12:51:18 PM »
Thanks, Terry. Is it this element that we're looking for?


"She'll make point five past light speed. She may not look like much, but she's got it where it counts, and I've made a lot of special modifications myself."

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Offline tactransman

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Re: Trans not downshifting when slowing down/rolling through stops
« Reply #9 on: August 29, 2008 - 12:57:05 PM »
Thanks, Terry. Is it this element that we're looking for?
  :grinyes:
Terry-tactransman 
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Union, Mo.
Give a man a fish and he eats for a day,teach him to fish and he eats for a lifetime.

Offline MyMopar

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Re: Trans not downshifting when slowing down/rolling through stops
« Reply #10 on: September 01, 2008 - 12:41:44 PM »
So I'll have to pull the pan to see if I have the part throttle kickdown.  The story is I had a TCI trans but it was leaking from everywhere.  I picked up a newly rebuilt 727 so it is a new rebuilt but it isn't my old trans that was rebuilt.  If I am missing that part, can I swap it out and be all set?
1969 (OO===]|[===OO)
1973 (OO/=====\OO) <---SOLD
1997 (O|||||O) <---SOLD

Smoke tires, not drugs!

Offline tactransman

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Re: Trans not downshifting when slowing down/rolling through stops
« Reply #11 on: September 01, 2008 - 06:49:53 PM »
If the VB on it now is different,you can swap the TCI VB on to it.
Terry-tactransman 
Torqueflite/Automatic Transmission Specialist
Union, Mo.
Give a man a fish and he eats for a day,teach him to fish and he eats for a lifetime.

Offline MyMopar

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Re: Trans not downshifting when slowing down/rolling through stops
« Reply #12 on: September 02, 2008 - 11:53:01 AM »
Thanks.  I'm still wondering why they would make a transmission with no part throttle kickdown.  Do you know what type of application would be used for it?
1969 (OO===]|[===OO)
1973 (OO/=====\OO) <---SOLD
1997 (O|||||O) <---SOLD

Smoke tires, not drugs!

Offline tactransman

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Re: Trans not downshifting when slowing down/rolling through stops
« Reply #13 on: September 02, 2008 - 12:11:35 PM »
It was on the early stuff only (I'm thinking around '68 and earlier did not have it)
Terry-tactransman 
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Union, Mo.
Give a man a fish and he eats for a day,teach him to fish and he eats for a lifetime.

Offline oldkimmer

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Re: Trans not downshifting when slowing down/rolling through stops
« Reply #14 on: September 07, 2008 - 10:29:13 AM »
 :canada:.................Your govenor is sticking..........it is located on  the tailshaft so the housing will have to come off to free it up......or u could install a performance govenor.............kim........
The beast has been unleashed........Thems the hazzards..........Unleash the beast......