700R4 shift points change when it warms up ??
 

Hi All,

I read through previous posts and finally set my TV cable correctly (I think) and my 700R4 shifts properly for the first 3 minutes after a start the car after it's been sitting overnight or cold. As soon as I get out of my house and hit this long road I normally drive on to go to work, the tranny correctly shifts into overdrive around 55-60. Three minutes later, it will start to get into overdrive at around 48 mph and won't lock up even when I get down to 35 mph in town.

I have to manually shift it into third gear then back into overdrive when I drive in town and depending on my speed. In short, it behaves corrdctly when cold and screws up as soon as it warms up.

WTF? I don't get it. I actually even run a B&M external cooler mounted just behind the fans in the engine conpartment. Could that be it? I don't want to put in front of the condensor since I already have somewhat of a cooling issue with air conditioning and I barely don't without AC. Is there a pressure drop I should look for someplace etc ??? Have I not set the TV cable correctly? It was soooo cool for the first three minutes but then turned sour on me... Help please. If anyone has any ideas please lemme know!

Thanks in advance to everyone that helps.
Lee

Wow. 40 views and not a single reply? Any tranny guys on the forum or is there something in my post that yall didn't like?

Pete K is the tranny Guru but haven't seen him post recently, expect he is busy. He will likely have some thoughts to share when he spots your post, hang in there.

When it is warm, it will not "lock up" in overdrive? Are you saying that it is slipping? If I understand you correctly you are describing a slip. That would indicate a worn clutch pack.

I honestly did not understand your problem...as you accelerate, at part throttle, you should go through all the gears and, in 4th gear, your converter should lock up at about 49 mph...it feels like another gear change but it is not...

:iagree: I may not be a transmission specialist but my other car has worn clutch packs and it shifts whenever it feels like and usually pretty hard :ack:

Hi PeteK,

Thanks very much for answering. I guess I go into overdrive at around 45-46 mph when it's warm (5 minutes after I start it up and get going).

If I start it up and immediately hit the road, It will shift into overdrive at around 57-58 mph which feels a whole lot better than at 45-46.

Anything below 50 mph and I want it to stay in third. If I slow down from say 60 to 45 then attempt to accelerate it stays in overdrive unless I manually shift to third or the big D.

I don't really feel it slipping as in "if I give it gas it won't move momentarily". I think I felt that in a different GM car a while back but I don't get that in this vette.

I guess I'm after a shift from third to overdrive to only occur above 55 mph. I also want it to shift back to third if I slow down from above 55 to mid 40's mph.

I hope I described what I'm looking for a little bit better and thanks again for your help PeteK!

Lee