Strange transmission problems?

[offroad]

Hi all, I've been reading the many posts here and found some to valuable.
A month ago I bought a 2000 ls v8 SST with 140K at the auction cheap and now have (I think) a tranny problem. If I accelerate from 0-50mph + the car runs fine. If I drive around 45mph the trans seems like it is searching for a gear. The tach does not go up.
Once it shifted hard at about 29mph and the check transmission light came on. Today on way to work it shifted hard and the engine stalled. Ran fine on the way home. No other warning codes or message lights. I need to go to Autozone to get the codes. From what I have read on this forum it could be a few problems.

Inside the Transmission.
Bad solenoid pack - any one of 3.
Bad valve body

Engine
Bad coils caused from leaking valve cover gasket making it seem like the transmission.

Did I miss anything else?

Thanks
Offroad

 

[FASTLLS]

I would get your codes ran then report back here with them.

 

[dNyce LS]

Mine is bucking at 45 also. Mine is misfirin a little but hasn't thrown a code yet (bummer), but also my trans has universal pennzoil fluid in it too, so idk if that could be causin mine also. And welcome to LVC

 

[FASTLLS]

When mine goes into 4th, the RPMs drop about 2-300 and when I let off they go back up. I believe that a PCM reflash will solve this. Also, when I had the scanner on mine, it was saying I was in 4th when it was in 1st.. Damn Ford.. :lol:

And it doesn't do it all the time. Just when it wants to.

 

[PRICE717]

no codes here just a slight bucking at 40-65 both under load and not. 01 ls sport i just bought it last week woman said it needs plugs her husband was a mech and didnt get to it she gave me the plugs jus havent go to it yet could that be it no codes or light just a sporatic bucking thought it was rear end??

 

[joegr]

no codes here just a slight bucking at 40-65 both under load and not. 01 ls sport i just bought it last week woman said it needs plugs her husband was a mech and didnt get to it she gave me the plugs jus havent go to it yet could that be it no codes or light just a sporatic bucking thought it was rear end??

I would say that you need to replace all of the spark plugs and all of the COPs (ignition coils) before you look anywhere else for this problem.

 

[mikeyswood]

http://www.lincolnvscadillac.com/showthread.php?t=80761