meatheadgn

iTrader: (1)

I have an LS6 Crate engine with a new GM 4L65E transmission. This is in a Cobra kit car. I had it running great and everything worked normal with the stock converter. It had about 500 miles on it so I put a different cam and a PTC 3000 stall lock up converter in it. I took it out after some tuning with HP tuners and it shifted normally and would shift into OD and the converter would lock. I took it to the dyno and it acted wierd as it did not want to rev up and just did not act right. We had it locked in third gear and inadvertently had the TCC locked up on several of the dyno pulls. On the drive home from the dyno it would not shift into OD as it acted like it was in nuetral. You can manually shift it into D and it runs but when the lever is put into OD it will act like it is in nuetral. I went home and pulled the pan and flushed out the cooler and lines and replaced the filter. I also cleaned out the shift solenoid A and B but they looked very clean. There was black residue in the bottom of the pan but it did not feel gritty, just dirty. I took the car out last night after turning off the code for the two shift soleniods and the car acts the same. It will shift into 1,2 and 3 normally but when it want to shift into OD it is like it hits nuetral. We manually locked the converter and it is working and will stall the car when it comes to a stop. I know I should not have locked the converter on dyno but that is the only thing that I suspect could have caused this problem. The car did have the check engine light on after the dyno with a code PO757 but that was fixed and now it still does not have OD. The car accelerates normally in the lower 3 gears and does not slip.
Your thoughts will be greatly appreciated as I will catch a whole bunch of sass if I need to take the tranny out for repair....it is the wife's Cobra and she told me to leave it alone when I took it apart for the cam and converter swap. Thanks much, in advance.

Gilbert@Ace Racing

You did not jack the wife's car up!!!!! Say it ain't so!

How much debris was in the pan when you first removed it? I would doubt that you'd see much metal with a fresh build, but seeing any clutch material is not good.

How does it do in the 2/3 shift when the shifter is in the O/D position?

g

T/A2000

sounds like an internal failure to me.. if it don't have codes in the system for the transmission than 9 out of 10 times its a bad transmission

meatheadgn

iTrader: (1)

It runs through all the gears normally when the shifter is in the OD position. It pulls good in first, second and third but acts like it is in nuetral when it shift to OD. You can also manually hold it in first, second and third and it seems to work great.

Gilbert@Ace Racing

In a 60E the 3/4 shift itself is fairly complicated, but in the end all we're applying is the Forward Clutches, the 2/4 band and the 3/4 clutches.

I suspect that there is damage to the 3/4 clutches.

g

T/A2000

there don't have to be a problem with any other gear to be an internal failure.. I had a car come in the other day that was completely missing second gear, and it would skip right over it like it wasn't even there.. but they were complaining about a hard 1-2 shift, lol it was going 1-3-4 lockup.. its pretty crazy how some of these transmissions will act when they are broke

meatheadgn

iTrader: (1)

Thanks for the tips. Special thanks to Gilbert for taking the time to call and talk to me about the car and how to go about fixing it. It looks like the trans will be coming out. Word to the wise, I guess you should not electonically lock the car the 3rd gear on the dyno or else it could hurt something. Tough lesson.
Thanks again for the assistance.