Overdrive/TC help needed

[SlickTR]

Well I verified I have OD today it wasn't shifting into 4th until about 60 played with the TV a bit and it shifts at about 50 now. The problem I'm having is that on my direct scan the ECM never shows it's in 4th so the tranny shifts but the ecu thinks it's in 3rd. Isn't there a 4th gear pressure switch or something and tells the car when it's in 4th? If so is this my possible fix? Anybody have a part number and some directions on how to fix this problem? And lastly does TC lockup only occur in OD because the ECM is not telling the TC to lock at all but I think it may be because it's not indicating 4th, am I right? Thanks in advance for the help.

 

[mikestertwo]

Well I verified I have OD today it wasn't shifting into 4th until about 60 played with the TV a bit and it shifts at about 50 now. The problem I'm having is that on my direct scan the ECM never shows it's in 4th so the tranny shifts but the ecu thinks it's in 3rd. Isn't there a 4th gear pressure switch or something and tells the car when it's in 4th? If so is this my possible fix? Anybody have a part number and some directions on how to fix this problem? And lastly does TC lockup only occur in OD because the ECM is not telling the TC to lock at all but I think it may be because it's not indicating 4th, am I right? Thanks in advance for the help.

There is a 4th gear switch but it has nothing to do with shifting. Depending on what chip you have determines if it will lock the converter only in 4th. Stock chips (BBKJ) will lock the converter in 3rd under the right conditions. Most aftermarket chips only lock the converter in 4th. If your not getting a 4th gear status then it is possible that is what is keeping the converter from locking. The switch is easy to change. It is screwed into the bottom of the valvebody. Does your converter lock when you connect "A" to "F" on your ALDL connector? Late shifting can be caused by several things. 1)misadjusted T.V. cable 2) low line pressure 3) sticking shift valve 4) internal leaks, ect. Are the 1-2 shifts and 2-3 shifts normal?

 

[SlickTR]

Its an extender extreme-G chip I believe it will only lock in OD. The other gears seem to shift fine, it use to shift into 3rd pretty late but adjusting the TV helped with that. Where exactly on the valvebody is the switch, isnt there a 3rd gear one as well, which one is 4th?

 

[mikestertwo]

Where exactly on the valvebody is the switch, isnt there a 3rd gear one as well, which one is 4th?

The 4th gear switch is on the right side of the valvebody pointed straight down. The 3rd gear switch is on the back of the valvebody pointed towards the rear of the trans.

 

[SlickTR]

THANKS! I appreciate the help