74 Bronco C4 transmission not shifting to high

[West Tn Dawg]

My Bronco has been shifting just fine. Took it to a car show yesterday with no problems.
I got in it today to take a spin and it doesn't seem to be shifting right. Had to stand on the gas to get it to shift. I don't think it is shifting into 3rd.
Why would it just start this all of a sudden? Modulator?

 

[B RON CO]

Hi, make sure the kickdown is not stuck. Up at the carb a spring should pull it forward, out of the engaged position. Good luck

 

[West Tn Dawg]

Thanks Ron, will check.

 

[oldiron]

also check to see that the vacuum line to the modulator hasn't come off.
Greg

 

[Lawndart]

Fluid level?

 

[Rustytruck]

Look in the vacuum hose at the modulator and make sure there isnt any tranny fluid in there.

 

[West Tn Dawg]

Look in the vacuum hose at the modulator and make sure there isnt any tranny fluid in there.

I'm in KY right now but plan to check all this come the weekend.
If there is fluid in there, what then?

 

[gnpenning]

I'm in KY right now but plan to check all this come the weekend.
If there is fluid in there, what then?

Replace it.

If that's the case make sure you replace it with the correct one.

 

[West Tn Dawg]

Replace it.

If that's the case make sure you replace it with the correct one.

Thanks!
I need your signature!!!!!;D

 

[B RON CO]

Hi, what Rustytruck is saying is: pull the rubber hose off of the vacuum modulator, on the passenger side of the tranny. If the rubber hose is wet with transmission fluid the modulator is shot. The fluid should never come out. You may as well check the whole vacuum hose from the manifold to the tranny for age, cracks and leaks, if the hose has the old dried up look, just replace it. Good luck

 

[gnpenning]

Thanks!
I need your signature!!!!!;D

It's not for sale but it can be bought !!!

 

[West Tn Dawg]

It's not for sale but it can be bought !!!

I see what you did! LOL!

 

[West Tn Dawg]

also check to see that the vacuum line to the modulator hasn't come off.
Greg

You nailed it Greg!
It had come off and was hanging down. Hose feels pretty hard. Plan to replace it tomorrow.

Thanks everyone for the suggestions.

 

[West Tn Dawg]

Replaced the vacuum line and transmission is shifting better than ever. It has been leaking for a while, it appears. My brakes were also giving me problems at idle. Found that this leak was robbing vaccum from the brakes. Brakes are now good as new!

 

[oldiron]

Glad I could help.
Greg

 

[Blue Bastard]

Man it’s nice when it turns out to be a low cost simple fix!



Sent from my iPhone using Tapatalk