It yours is the traditional 4x4 system, then yes that is normal on dry pavement. You should never use the tradition 4x4 on paved roads as it can cause problems. The 01-02s had the multimode (push button) transfercase which is like an AWD system letting you drive in 4x4 on pavement. This option was on some 2000s, I believe it was only the limiteds though.
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-2001 Sport Edition 4runner 4x4 2nd gen Supercharged-
The bucking/slipping and difficulty turning is due to the drivetrain buckling and straining. Don't use the 4wd on pavement unless snow cover as already mentioned above. That's a good way to break something
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98 Limited V6 w/310k Miles l 4X4 l Rear Locker l Goodyear Duratracs 265/75/16 l 199mm Tundra Brake Mod l Cobra 800 Watt Power Converter l Uniden Pro 520 XL CB Radio l Bilstein HD Shocks l CS 144 Alternator