Bronco II Overdrive problem

[w3dbj]

Hi,

I'm a new Bronco II owner. It shifts fine, doesn't slip, but there is a problem with overdrive on the transmission. It will shift into and out of OD very rapidly and will sometimes downshift to second. Taking my foot completely off the gas pedal when it first goes into OD and not touching the gas for a few seconds lets it stay in OD.

I checked the vacuum control on the side of the transmission and it's holding vacuum just fine.

Before I do a transmission pull, is there anything I should look for outside of that?

Thanks

 

[4.0B2]

check the gear on the vss (vehicle speed sensor) in the t/case or where ever yours is. make sure it's not worn there and feel inside the t/case where the sensor goes and make sure the gear in there is okay to.

this being said, does your speedo work fine? or does it kinda go up and down while picking up speed?

 

[Shran]

I had the same problem with one of my old Rangers and tracked the problem down to the overdrive servo or 3&4 shift solenoid, but can't remember which. I sold the truck before I fixed the problem so that is all the information I have.

 

[jrpdash9]

i got a od problem to and my speedo goes up and down till about 35 40mph. whats ur thoughts behind it affecting the od

 

[4.0B2]

i got a od problem to and my speedo goes up and down till about 35 40mph. whats ur thoughts behind it affecting the od

check your vehicle speed sensor gear and the gear in the t/case (drive and driven gear)... those wore down and the truck doesn't know the speed its going and WEIRD things will happen...trust me. fix that problem and then go from there.

 

[jimbII]

mine did it all the way on the 70 mile trip home. after going through checking and fixing all the vacuum lines , the problem went away. 1985 B2

 

[jrpdash9]

sweet. it was working good then it was hit or miss. now it dosent work at all. ill have to check that out

 

[jrpdash9]

ok i pulled the speed senor out. the gear was fine. i played with it alittle and the needle dosent bounce as much but still no od. if its any help in od when u take ur foot off gas it goes down to idle. no resistance at all

 

[4.0B2]

ok i pulled the speed senor out. the gear was fine. i played with it alittle and the needle dosent bounce as much but still no od. if its any help in od when u take ur foot off gas it goes down to idle. no resistance at all

Mine does that now....

 

[jrpdash9]

oh sweet. i couldn't remember if mine did it before it acted up or not. well she runs. i guess just drive it