OM says greasing is a once a year OR every 200 hour interval (whichever comes first).
I'd agree with above posters that there that there is little chance there has been damage to be concerned about.
Service interval info cut and paste from x758 manual:
Servicing Your Machine
IMPORTANT:
Avoid Damage! High-pressure washing can damage to machine components.
Operating in extreme conditions require more frequent service intervals:
- Engine components become dirty or plugged when operating in extreme heat, dust, or other severe conditions.
- Engine oil can degrade if machine is operated constantly at slow or low engine speeds or for frequent short periods of time.
Use the following timetables to perform routine maintenance on your machine.
Park the vehicle safely. (See the Safety section.)
After First 50 Hours
- Check rear wheel bolt torque.
- Change transaxle oil and filter.
- Check and tighten clamps for cooling and air intake system.
- Check and tighten hardware.
Every 100 hours or 12 Months (Whichever Comes First)
- Clean radiator and hydraulic oil cooler screens and cooling fins.
Every 200 hours or 12 Months (Whichever Comes First)
- Change engine oil and filter.
- Check fan belt tension.
- Check and clean battery.
- Lubricate steering spindles, axle pivot, steering cylinder, and engine drive shaft.
- Check the hydraulic full-time 4-wheel drive (HFWD) oil level.
- Check tire pressure.
- Check and tighten clamps for cooling and air intake system.
- Change fuel filter.
- Monitor air filter restriction indicator for service of air cleaner.
- Clean radiator and hydraulic oil cooler screens and cooling fins.
- Check and tighten hardware.
- Test or replace radiator cap.
Every 200 Hours
- Change transaxle oil and filter.
- Check and tighten rear wheel bolt torque 88 N·m (65 lb·ft).
- Clean radiator and hydraulic oil cooler screens and cooling fins.
Every 1000 Hours or Every 2 Years (Whichever Comes First)
- Change engine coolant.
- Check/adjust valve lash.
Grease
IMPORTANT:
Avoid Damage! Use recommended John Deere greases to avoid component failure and premature wear.
The following grease is recommended for service:
- John Deere Multi-Purpose HD Lithium Complex Grease
- Grease-Gard™ Premium Plus
Not all grease types are compatible; John Deere does not recommend mixing greases. If using any product other than the recommended grease in service, purge any remaining grease from the system before application. If not practical, grease twice as often until all old grease is purged from the system.