Im sure this has been answered somewhere on this site but i cant seem to find it anywhere. Does any one know the stock stall for a 99 4.3 4x4 torque converter with a 700r4 tranny.

 

I want to say that stock is around 1650RPM for these torque converters. There are 3 main stall speeds for stock converters for the 700R4/4L60/4L60E, 1200-1400, 1611-1654, and 2000. It depends on the application.

 

is there any way to tell by looking at it (numbers/markings)

 

From what I could find, there should be a 4 digit code somewhere on the converter.

The 2nd character is the stall speed:
G,H,K = 1200-1400 stall
E,F,L = 1611-1654 stall
B,C = 2000 stall

Some more fact finding, it looks like the torque converter used for the 98+ s-series will have code TLBX or TLCX.
T = 12.5" diameter 30 spline
L = 1654RPM stall speed
B/C = PWM CARBON FIBER LINING 300# / 330# respectively
X = L/U 3 Lug Gas