8PCS TT Motor DC Electric Motor 3V-6V Dual Shaft Geared Motor Magnetic Gearbox Engine Motor for Arduino Smart Car Robot

This is an excellent value for simple motor and gearbox assembly. All 8 tested fine under light load - one assembly acting as a rear-drive trike pulling a trailer - approximately 250 gram total load. I also tested a 4x4 assembly drive under a 500-600g load. They worked at low speed.I did a full disassembly of the gear box, the gears and axels have a pit of play that I think would be stressed to breakage by higher torque usage. About what I would expect at this price point.That aside, for small builds of lightweight cars, these are great.

I ordered this 8-pack of DC motors with housings from D-Flife for a diy car. I only needed four, but having extras is always a good thing. The motors are securely seated in the housing with a flexible strap, so they can be easily removed if needed.Seven out of the eight work fine. The eighth one's motor works well, but there is something wrong with the housing. I can't get the motor to turn the axles. When I need it, I'll take it apart to see if I can fix it. If anything else, I can use the motor for a different project without the housing.Also worth noting is the contacts on the motors are very thin and flimsy. It is far too easy to bend and therefor break them.Overall, I got eight good motors and seven housings. I'm happy that I got what I need but still disappointed with the bad one.