Hey everyone I just wanted to get some feedback on what to do with my current situation. Ok so I recently installed a new 4L65E into my SS fully built with a shift kit and a 2400 stall. Well it was not wanting to shift 2-3 and no matter what the guys at Vengeance did in the tune it wouldn't shift till finally they got it too some how but its a VERY slow shift and I was throwing the P0751 code before all this so we thought it was something wrong internally not with the tune. I just got the car back after having the entire trans taken out and gone through and having a new valve body installed and now for some reason it will shift 2-3 fine just VERY slow like before BUT now I have NO overdrive at all. I can stop on a complete level surface and take my foot off the brake with the car in OD and it wont move even an inch. Also if I'm on a hill and in OD and let my foot off the brake withought giving it any throttle it will roll back maybe not even an inch and then just stop as if I put it in park on a hill and let off the brake without the E brake being on if that makes sense?

I'm just completley lost as to what the problem is at to if it's the tune and something wasnt programmed right for the new set up because I know the P0751 code wasnt deleted because it threw it multiple times after leaving Vengeance or if it is the actual converter itself but it was supposed to have been checked along with the rest of transmission before I got it back yesterday.

I'm supposed to have the car back at Vengeance on Monday but honestly I wanted to know if there was anything else I could try/do to get my over drive working again because I don't have access to a trailer and it's about a 1 1/2 hour drive from where I am to Vengeance down the interstate and I'm afraid if I drive the car there with the shape it's in I could damage something even further. I also wanted some feed back on my problem as to what you guys think it is/might be.

Thanks!

 

BUMP! I need to know if it's ok to drive the car with it acting this way

 

I'll take a stab at it. The P0751 is for the 1-2 shift solenoid. The 1-2 solenoid is required to get 1st and 4th. Chances are you're starting in 2nd and only getting the 2-3 shift. If the trans was just gone through then you could have a pcm problem not controling the solenoid or wiring problem between the pcm and the trans. Either way you're likely to burn up the trans by driving it.

 

This is an internal problem in the trans.

 

Though I do think the trans has mechanical problems based on what he's described, the symptoms quoted below are not that unusual with a stall converter even as small as 2400 because some brands have more slippage than others. Of course you should always use the brake to hold the car on an incline.

 

OP - Can you manually shift the car through the gears? If you have a scan tool, use the bi-directional controls to command the shifts (and TC lockup) to see if the solenoid is on or off.

 

I can manually shift fine with the shifter with no problems until 4th. Like if I go through all the gears manually I'm fine until I bump it from D to OD then nothing happens. It's like that gear doesn't even exist anymore. And I don't have access to a scan tool...

 

Bummer on the scan tool. That could help pinpoint the problem. It does sound like a mechanical issue (shift solenoid), but once again it's hard to tell over the internet. Give FLT (sponsor here who posts in the Auto section) a call and run it by them to see if they can give some tips to help. I would also contact the builder about the issue and don't drive it to play it safe.

 

the sprag that's in the foward input drum is damaged or was put in wrong . if you can manually shift 1-2-3 then it will just rev in od this is the problem.