99 Suburban 4x4 knocking sound when turn right

[Joy1]

I have a Suburban-99 4x4, when I turn right, I can hear a knocking sound in the front of the car. It seams to came when I drive under 35 miles (60km)
All bearing in the front case for four wheel drive is new, but there is still play on left side on the case, where the drive shaft to left wheel is connected, but the car repair shop say some play can be tolerate. Also 2 crosshead bearing is new, 1 in drive shaft to the rear, and 1 in drive shaft from gearbox to front four wheel case.
Somebody who has the same problem, or can help me? Thanks!
Joy1

[777stickman]

Most likely the left CV joint as you said there is play in it. Really need to get all 4 wheels off the ground and run it in 4Low with tranny in Low and turn it side to side to find source of noise...............Steve