Can someone verify a deep noise in your H3

[tacocat]

4Hi (part-time, or 4Hi Lock) "Locks" up the differential. In normal 4Hi full-time mode, the front wheels and rear wheels are able to turn at different speeds. IN locked mode, the front and rear wheels must turn at the same speed.

Differentials are designed to allow two wheels to turn at different speeds without binding. When your differential or transfer case are locked, you are not allowing your wheels to turn independent of each other.

What you are hearing is drivetrain binding and the tires breaking traction on pavement.

Your vehicle is operating perfectly. DO NOT turn on 4Hi Lock or 4Lo Lock on pavement. These functions are only to be used in cases where the terrain allows tire slippage, such as deep mud. Your drivetrain will have less binding issuses in those cases.

BTW, that is why you see drivetrain breakage on many rock crawling trails. Wheelers need to be locked for maximum traction, but the rocks provide excellent traction. Often times, the breakage is directly or indirectly related to drivetrain bind.