As you know this main drive shaft is common on the 3900, 3900W, 4000 & 4100 cranes.

We've overhauled this assembly with new bearings, seals, gaskets, hardware, etc... and rebuilt it to a 4100 print.

Can easily be modified for a 3900, 3900W, or 4000 - but the assembly number would be different for each model crane.

Gear are very good at 90%+ life remaining.

We also have available and will ship with this assembly to the buyer the # 181706 pot gear which is also in very good condition to match the spider/pinion gears.