No clue what years yours is.
Here is for a 2002, YES 2wd, and 4wd are the same. (15706 Tahoe/Yukon C/K)
https://www.gmupfitter.com/wp-content/uploads/2021/05/2002_LD_CKTruckNew.pdf (page 116)
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Here is a 2005, (thinking, AT THE MOST that 99-02 might be one, and 03-06/07 might be another).
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2002 and 2005 C/K SUV frames are the same. Don't hold me to it, but IT LOOKS LIKE all NBS short base SUV frames should be the same from 00-06 and 2wd to 4wd (based on 02 and 05 being the same). The longer SUV frames look to be the same from 2wd to 4wd. (* 2000 was a split year. They made OBS and NBS in 2000. I am only referring to NBS, just like 99, & 07 were split year for pickups).
What it also looks like is the 2wd and 4wd PICKUPS have different frames in the front. BUT, the SUV has the same FRONT frame as the 4wd pickup.
View attachment 858
The 2wd and 4wd pickups seem to have the same frame rails, just a different crossmembers and mounting pads. (It looks if someone wanted to modify some of the frame mounts they could swap between 2wd and 4wd pickup). Same rails, different frame.
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