black346

Well the saga continues.... Got the driveshafts installed. Reverse and drive work just fine. Get the truck up to about 15 MPH and all hell breaks loose. The thing shutters/shimmys (for lack of a better word) real bad and makes some clatter. While it's doing this the truck won't gain any more MPH. The clatter will stop when the truck slows down. Reverse acts fine. Also the truck acts exactly the same when you put the gear selector in 1st. At first I thought it was acting up when the truck was trying to shift into 2nd but I don't even think it got that far. With the gear selector in 1st it shouldn't be trying to shift at all. When I got back to the house I barely had enough power to get up the driveway. I had to get a pretty good running start. The fluid still smells fine. Doesn't smell burnt or anything. The trans definitely got warm durning this brief drive. Pan on the trans was warmer than the engine oil pan. Also no SES lights so I'm assuming the 4L80E segment swap I did in EFI Live went smoothly. I'll try and get a video of this tomorrow but I almost hate to keep driving it.

Just some history on this. I bought a new reman serta 4L85E trans from GM. Put in a trans go shift kit and added this Vigilante converter.

Thoughts?

I don't even know where to start. Was thinking about maybe putting in the stock 4L85E converter to see if I still had issues. This would rule out having a bad torque converter.

What a mess.....

black346

Update***

Got her fixed! Runs like a bat out of hell with the PI converter and shifts perfect! Yay... Didn't get to drive much tonight. Will put some more miles on it tomorrow.

I had messed up the tune. I had swapped over all the 4L80E trans calibrations to my stock file thinking that was all I needed to do, but apparently there are "hidden" tables or settings that don't get copied over unless you do a full "segment swap." I did the segment swap and she runs great.

Anyways thanks for all the feedback you guys have given. Hope I didn't screw up anything driving it around a couple blocks with the wrong tune. We shall see.