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  • 1965 - 1973 Classic Mustangs -General/Talk-
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c6 shifting strange !!

  • Thread starter Thread starter rbjb99
  • Start date Start date Aug 27, 2009
R

rbjb99

New Member
Aug 27, 2009
2
0
0
Aug 27, 2009
#1
  • Aug 27, 2009
  • #1
Hi, I'm new to the site and am hoping someone can help me.

I have a 73 351c c6 all stock, just finished rebuilding the car and when I drive the car if I put it straight into drive and go, it wont shift until the car is screaming up the road, if i put the car in 1st then move it up to drive it changes up and down perfectly all day long.
I don't have to shift it manually, just down into 1st then up to drive and its ok.
If i stop and put it in park then straight down to drive it will shift weird again.

Anyone had this problem?? I thought it may be the modulator but why does it shift right one way and not the other???

Thanks for any help.

Rod
 
S

stonecoldtx

Member
Aug 4, 2007
214
2
18
Dallas, TX
Aug 27, 2009
#2
  • Aug 27, 2009
  • #2
rbjb99 said:
Hi, I'm new to the site and am hoping someone can help me.

I have a 73 351c c6 all stock, just finished rebuilding the car and when I drive the car if I put it straight into drive and go, it wont shift until the car is screaming up the road, if i put the car in 1st then move it up to drive it changes up and down perfectly all day long.
I don't have to shift it manually, just down into 1st then up to drive and its ok.
If i stop and put it in park then straight down to drive it will shift weird again.

Anyone had this problem?? I thought it may be the modulator but why does it shift right one way and not the other???

Thanks for any help.

Rod
Click to expand...

What exactly did "rebuilding the car" encompass? Did you do any work on the transmission?
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
6
0
south louisiana
Aug 27, 2009
#3
  • Aug 27, 2009
  • #3
Go to your local Advance Auto Parts. There in the transmission additives shelf you'll find a bottle of Lucas Transmission Treatment. Buy a bottle and pour it into the C-6. Problem solved after about two laps around the block.
 
R

rbjb99

New Member
Aug 27, 2009
2
0
0
Aug 28, 2009
#4
  • Aug 28, 2009
  • #4
will give it a try, thanks for the help
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
6
0
south louisiana
Aug 29, 2009
#5
  • Aug 29, 2009
  • #5
It's probably gummed up from sitting too much. That stuff cleans the gum off the valve body parts. I've used it in an E4OD that was acting up and a 62,000 mile C-6 that was 38 years old (and never rebuilt) It worked on both transmissions. The C-6 was doing the same thing yours was.
 
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