When I printed this nice Jeep
I was missing the base for it.
I designed the base in two version: all printed and version with a 3 mm rod for the axle.
Both work fine, I'm actually surprised how well the all printed version does, wheels spin as crazy.
Printer: Print Rite DIY
Infill: 10 - 20 %
Printed in PLA. Print with 4 perimeters for nozzle 0.4 and 4 top/bottom solid layers
The "all printed" version maybe will need to retouch the hole with a 8 mm drill if it prints too small. Sand a little all four axles and apply and snap the wheels on. Add some silicone lubricant it really helps.
The "version with metal rod" you will need a 3 mm diameter rod and 51 mm length
If required retouch the holes in the wheels with 3 mm drill and the holes in the body with a drill little bigger than 3 mm 3.2 - 3.5 mm snap the wheels on the rods and apply some super glue.
I play with electronics, kids toys, replacement parts, puzzles,...