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Slipping at rest

  • Thread starter Thread starter Cool Wheels
  • Start date Start date Nov 19, 2005

Cool Wheels

New Member
Jan 26, 2004
103
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0
Nelson, BC, Canada
Nov 19, 2005
#1
  • Nov 19, 2005
  • #1
Kinda a sounds like a strange thing to do doesn't it...well maybe if you're drunk enough..

Tranny is C4 Auto: Happens when cold and very low speeds and rest. Fluid level is right. 1st gear in Drive mostly and also happens in reverse occasionally.

Only for the 1st couple minutes when its cold, then it's fine. This just started not too long ago. Has me kinda freaked.

Book says maybe bands, servo, oil pump, valve body, governor?

I know you guys know your stuff here. Any ideas what order of the above I should start with? Experience with this anyone?:Teh-Win: :SNSign:
 

2muchtime

Founding Member
Jan 30, 2002
890
1
16
MA.
Nov 19, 2005
#2
  • Nov 19, 2005
  • #2
slipping at rest?? thats an odd way of saying it. trans slipping at idle in D??
what type of tranny fluid are you using.
im pretty sure back in the day ford was using type F for their autos
which had a different consistancy to it (mineral spirits or something)
compared to dexron3..
how many yrs and miles on this tranny??
have you done a filter/fluid change latety.
most of the components you listed as problems require a complete tear down
for inspection..
it could be something as simple as wrong fluid.
could be broken vaccum line
could be that the filter is not seated properly causing low flow..
could need a clutch band adjustment
could need a complete rebuild..
check the basics first ..pull the pan for insp;
 

Cool Wheels

New Member
Jan 26, 2004
103
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0
Nelson, BC, Canada
Nov 19, 2005
#3
  • Nov 19, 2005
  • #3
There's been no changes to fluid lately. I've always put type F in it.

How do I find the vacuum line? Can I use a standard (engine) vacuum tester?
 

COBRA 7

Founding Member
May 19, 2000
466
10
39
Bangor, Maine
Nov 19, 2005
#4
  • Nov 19, 2005
  • #4
Cool Wheels said:
Tranny is C4 Auto: Happens when cold and very low speeds and rest. Fluid level is right. 1st gear in Drive mostly and also happens in reverse occasionally.

Only for the 1st couple minutes when its cold, then it's fine. Experience with this anyone?:Teh-Win: :SNSign:
Click to expand...


My C-4 has acted like that for years. I have changed the filter and F-Type fluid many times. Finally I just filled it to the correct level of fluid on the dipstick. ( Engine warmed up and running in park. ) Then I added half a quart more and it works fine.
 

Dano78

Founding Member
Nov 1, 1999
2,633
1
47
Vancouver, WA
Nov 20, 2005
#5
  • Nov 20, 2005
  • #5
Yeah I've noticed that to in a couple of IIs aswell. Kinda thought that Ford mis-marked their dipstick or something. Try adding 1/2 quart like Cobra 7 says. Otherwise, could check the adjustment on your bands too, thought if it's slipping like that (or hydraulically comming out of gear) messing with the bands probably won't do you much good. The vacuum (vacuum modulator) really only affects the tranny durring it's shifting, either up or down, when a given load is applied.
 

Turbo II

Founding Member
Nov 19, 2000
1,537
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0
Alberta, Canada
Nov 21, 2005
#6
  • Nov 21, 2005
  • #6
I battled this problem with my '77, the symptoms you describe were what was happening on mine. First tried fresh type F and filter but that didn't do it, eventually I tore the tranny down and installed new clutch packs in both the forward and reverse-high clutches, this helped but not completely so I had to pull it again and install new piston seals on the clutch pistons...been trouble free now for the last 10,000 miles.
I would check the simple things first (fluid/filter), if that doesn't do it, it's probably time for a rebuild. If you decide to try it yourself, don't get lazy like I did and only replace some parts, replace every seal that comes with a rebuild kit the first time! The cost of type F starts adding up when you pull the tranny apart a few times!

Francis "Turbo II"
 

Cool Wheels

New Member
Jan 26, 2004
103
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0
Nelson, BC, Canada
Nov 21, 2005
#7
  • Nov 21, 2005
  • #7
Hey thanks guys. This forum is a life saver.

Geez, I hope I don't need a rebuild. I just had it done in 1990 or thereabouts, and I've only put on about 30,000 miles since then.

I like the sound of that "it's normal" idea better. It just really sucks if a car's heading for you and you have no gear for a sec

Guess I should get that slow leak fixed too.
 

2muchtime

Founding Member
Jan 30, 2002
890
1
16
MA.
Nov 22, 2005
#8
  • Nov 22, 2005
  • #8



Cool Wheels said:
Guess I should get that slow leak fixed too.
Click to expand...
 
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