Technically, you should not rollover doing donuts...on a flat plane with no irregularities in traction coefficient or surface features.
The issue of concern is with surface imperfections, which will interupt the smooth transition of polar moment, and result in lateral acceleration in excess of the projected tire slippage required to execute a donut.
This condition will result in the tire(s) traction providing resistance to the lateral forces, and the truck's weight and center of gravity continuing in an outwards direction, albeit with the outer tire(s) remaining in the same arc.
The truck's body and frame with therefore follow a wider arc than the tire pathway.
This results in the truck's frame and body crossing through the plane of the tire pathway arc.
If the above crossing results in the truck's center of gravity crossing the chord of the arc, the trucks's body and frame will tend to continue in an arc outside of the tire path, with a secondary continuance downwards to the ground at the outside of the chord.
The above typically results in the side of the truck hitting the ground.
In a donut, the rear outer tire is typically the most critical interceptor of surface irregularities, and tends to upset the balance of the rear slippage angle, essentially tripping the truck such that it hits first on the outermost front fender area, rolling onto the roof and hood areas, and then, rotating due to the momentum involved.
This is sometimes referred to as doing a donut and flipping over.
Of course, the higher the center of gravity, and the less perfect the surface, the more likely this is to occur.
It is therefore possible to execute donuts in a parking lot w/o flipping over, albeit the above variables must be considered to avoid flipping.
So, I hope that helps!
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- TJ
2001 Xterra '03 VG33, SE 5 spd, 305/70/16's, Revolvers, UBSkidderz, Doubled AAL's, 3"SL/2"BL, winch/bumpers, skids, sliders, OBA, Snorkel, pine stripes....
Friends don't let friends drive stock.
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