thank you so much!
is there a difference between 998A2 and any other 998? can I search for 998 ball joints and get what ever comes up?
Yes, there is a difference between the two.
The M998A2 has heavier suspension and drivetrain parts.
M998 and M998A1 drivetrain uses either 7.7k or 10.3k rated halfshafts. The M998A2 12k halfshafts use a different size spline end going into the hubs.
Also as noted above the ball joints.
Transmission and transfer case are different.
Gearing in the differentials is different.
There are many differences between the two under the truck, so you are best served looking in the parts manual for the part number for your truck and searching for it.
When looking at parts, you want to make sure that the part you order has the UOC (Usable On Code) of "NNN" after the description, as that's the code for the M1123.