I have a 2000 GMC Sierra with a 5.3L V8 and my transmssion does this weird thing were when Im just cruising with my foot lightly on the gas it will drop rpm suddenly and kinda bog. if i push harder on the peddle the tranny starts to kinda shutter until i hit the kick down point and then its fine again until i go back to lightly pressing the gas peddle. I also tried tapping the brake a little bit when i do it and itll make it go back to normal rpm for a few seconds and then just drop back down. I can just hit tap the brake and everytime its like it clears the problem for a few seconds and then it happens again. Anyone know what this exact problem is?

Have the truck scanned at a transmission shop to see if any trans codes show up. It kind of sounds like your torque converter isn't locking and unlocking right.

When was the last time you did a tune up?

TSB # 01-07-30-023A
Harsh 1-2 Upshift, SES, MIL, or CEL Illuminated, DTC P1870 Set (Replace Valve Body)
1996 Buick Roadmaster
1996 Cadillac Fleetwood
1999-2000 Cadillac Escalade
1996-2000 Chevrolet Camaro, Corvette
1996-2000 Pontiac Firebird
1996-2000 Chevrolet and GMC Light Duty Truck Models
1996-2000 Oldsmobile Bravada
with 4L60-E Automatic Transmission (RPO M30)
Built Prior to January 15, 1999 (Julian Date 9015)
This bulletin is being revised to update the Parts Information.

Please discard Corporate Bulletin Number 01-07-30-023 (Section 07 -- Transmission/Transaxle).
Condition
Some customers may comment on a harsh 1-2 upshift and the Check Engine Light or Service Engine Soon indicator is illuminated.
Diagnosis
Typically, these vehicles will have been driven more than 32,000 km (20,000 mi) before this condition occurs.
The scan tool may show a DTC P1870 set as a history code.
A harsh 1-2 shift or DTC P1870, caused by wear in the control valve body, may be difficult to duplicate when the transmission temperature is below 93°C (200°F).
Cause
The condition may be due to wear in the control valve body. This wear occurs in the bore that contains the TCC isolator and regulator valves, and results in poor, or no, TCC apply.

Important
DTC P1870 is a type B code. The conditions for setting the P1870 DTC must occur on TWO CONSECUTIVE TRIPS (ignition cycles, with a drive cycle) before setting a P1870 history code.
When the conditions for setting DTC P1870 are met (first trip), the PCM commands maximum line pressure and harsh 1-2 shifts are the result.
This may result in a harsh 1-2 shift with no history code if the conditions for setting the DTC required for the second trip are not met, on two consecutive trips (Ignition cycles, with a drive cycle).

When the conditions for setting the DTC are met, on the second consecutive trip, a DTC P1870 is stored as a history code.
When the P1870 code is stored, the PCM will turn on the Service Engine Soon (SES), Check Engine Light (CEL), or Malfunction Indicator Lamp (MIL).
Correction
Install a control valve body with the revised TCC regulator and isolator valves. These valves are used in all transmissions produced after January 15, 1999 (Julian Date 9015), and all of the service parts currently available through GMSPO contain revised TCC regulator and isolator valves.

Important
If all of the following conditions are true, it is not necessary to rebuild the transmission or to replace additional transmission components beyond the control valve body.
Transmission operation is normal before the transmission reaches operating temperature, or before DTC P1870 is set (no slips, flares, or missing gears).
The torque converter is not blue or overheated.
The transmission fluid is not burned or has no burned odor.
The transmission fluid pan contains no abnormal debris (clutch material, bronze, brass, or metal fragments

i have no codes and ive even done a datastream to make sure that the tcc is being told when to lock up and everything seems to be normal

Tuneup?

like what kind of tune up? lol

It may not be the transmission, but the engine that is causing the problem. I have an issue on my car where the engine will stumble under very light acceleration. If I am in bumper to bumper traffic and want to move up a few feet, it will sometimes stumble. If I am on cruise control and it calls for slight acceleration to compensate for going up a hill, it will stumble. Never under mild to full acceleration, only the slightest of acceleration.

I suspected the throttle position sensor, but a scan shows uniform increase as I push the gas pedal down. I don't know what the answer is, but I just wanted to suggest your problem may not be transmission related.

thanks ill look it up

what are the common symptoms for a bad torque converter or the sylenoid?