I have a bit of an interesting transmission issue. I was driving home from the gym the other day and noticed my truck wouldn't downshift into first after stopping at a light. I can manually select it and it will go into first fine, but it won't do it with the column in 4th or 3rd.

I pulled the pan and there was absolutely no shaving in it, and the fluid still looked pretty good.

 

weird. Hopefully one of the transmission guru's will chime in.

 

I have a delayed downshift into first @ a stop. Feels like a bang after I stop. No idea.

 

Mine isn't a bang at all, it just doesn't shift into 1st 3/4 times now. There's no unusual noises. I was hoping maybe it's just a dirty MAF sensor as I've heard those have been known to cause issues, but I'm not getting my hopes up just yet. I may pull the tranny and have my builder just refresh it and pull my ss3600 while I'm at it. I think I'm ready to get out of the game for a while until I have a steady income to support it.

 

Smartest/Hardest thing to do.

 

mods to the truck?

 

It has an ss3600 converter, 224/224 on 112 lsa cam. Built 4l60e with the vacuum mod an a 150 shot of nitrous. It doesn't slip at all on wot runs with the nitrous either.

 

Have you checked over the tune?

 

I haven't. It hasn't changed in over a year though.

As a new update: I now do not have 4th gear. 3rd will lock up fine but it won't go into 4th unless I completely let off the gas and even then it will immediately shift back into 3rd when I give it any throttle.

Also Like I said, I cab manually put it in 1st and it goes into 1st fine.

I do have efi live so if anyone has any recommendations on what to scan for I would appreciate it.

 

have you tried reflashing your current tune into the truck?