In all my years as a technician(former), I never encountered this, in an LS motor. I am having an issue, at part throttle...roughly 1400-1700rpms...REAL MILD throttle input...say high gear, 45-50mph...you can feel a very strange flutter in gas pedal, I can audibly here the exhaust note change in the vehicle, and power seems SLIGHTLY less then normal, while making this noise/slight vibration. If I give it 2% more throttle, it goes away...if I accelerate harder, no issue. To me, if I had to guess...maybe displacement on demand related? Maybe lifter related?

It's like a weird flutter type noise(exhaust note) and feeling...translated to my gas pedal. I have a ported TB,custom intake, tune and custom exhaust. Exhaust appears fine and not rubbing anything.

Sound familiar to anyone?

 

Torque converter shutter maybe.

 

Truthfully I do not have a lot of technical backround in automatics.....but I was taking a technician for a test drive this past week, and I mentioned to him it almost feels like a converter fluttering. He leaned more towards DOD... but not experiencing it before, I don't know. I can duplicate it, for as long and as constant as I want, just as long as I keep the rpm exactly where it is, and do not change throttle input.

Sound like shutter? Thanks

 

Holy ****, you just described it to a T.
I have yet to find out what the problem is. But, with help from some fine folks here and LS1tech I'm narrowing it down to the tcc regulator valve kit. If that doesn't fix it. Who knows, hah. Its been going on for so long now, I'm used to and it sucks.
This is my story.
https://www.performancetrucks.net/fo...e-help-523998/

 

Wow dude,...I just read all that...stressful...especially since its been going on a year and a half for you.

Mine FEELS like it was a little worse over the weekend. Totally fine on throttle...at load...fine...part throttle...45ish...shudder... starting to get annoying.

I do have a 4l80 that I want to install in it but I wanna try and figure out my issue first.

 

It has been a nightmare. I have given up on pretty much any shops. I'll figure this out myself (with the help of PT and LS1tech) I'll be doing that valve as soon as I have a long weekend. Until then, I'll deal with it. It sucks, I'm not gonna lie.

I'm debating about going the 4l80 route to. I'm thinking the same thing. If I can figure it out and resolve the problem, great. If not an 80 will be going in.
Where did you get your 80 from?

 

The 4l80e was given to me, with a transfer case attached to it, as well as a torque converter.

I just have to either buy what I need to make it all fit, or make it work ourselves. Trying to make time, and money to mod my daily, isn't normally in the cards but, I think with my tow intentions, the free 4l80...with a transfercase, and I have a Z71....I figured it was too perfect of a deal not to do.

Now, just gotta come up with the money and time to do it.

 

Side note: I have a very similar feeling vibration when coming to a complete stop...for example, the last 5 feet of a stop, when approaching a stop light intersection,...that last 5 feet or so, I feel a very similar vibration in the chassis. Almost wonder if I have a mount issue...