Abstract We have made measurements of the torque induced by an applied magnetic field of 1 T on lead-doped Bi2Sr2CaCu2O8 superconducting crystals at liquid nitrogen temperature. Lock-in transitions are detected at doping values of x = 0.07 and x = 0.13 in Bi2-xPbxSr2CaCu2O8, consistent with the predictions of a Lawrence-Doniach model which considers the superconductor as a lattice of superconducting sheets separated by insulating spacers coupled by Josephson tunneling, rather than an anisotropic London model, which treats the superconductor as homogeneous and three-dimensional, with different effective masses m_{c} and m_{ab} in different directions. We find no evidence of the lock-in transition for x = 0.30, suggesting that there has been a crossover to the London regime as a result of the higher level of doping; we cannot reach a definite conclusion in this regard, because the quality of this sample may have been too poor to produce a lock-in. We have examined the Kogan formulation of the anisotropic London model in detail, and have developed a refinement to the theory as it is applied to experimental data. This refinement will force the reevaluation of earlier measurements. We have also obtained values of the superconducting anisotropy factor gamma = (m_{c} / m_{ab})^{1/2} for doped and undoped samples; the decrease in gamma by an order of magnitude which we observe over the range of doping is consistent with the measured resistivity anisotropies and the Lawrence-Doniach model for these materials.