Those front diff zerks....

I asked chatGPT so keep that in mind. Here is what is says is the typical service life for each.

• Non-greasable: 70-100k miles
• Greaseable (properly serviced): 100-150k
• Greaseable (not properly serviced): 50-70k

I think I would rather just have non-greasable joints and replace them every 8 years.

Also read the next post below from @jmneill

 

Outside of downright abuse, I've never replaced a u-joint, and I've had at least a half dozen personal and work trucks that saw 300 - 400K on the clock before something other than universal joints finally ended their lease on life.

 

I bought the Core Gear coupler from Home Depot and it connected easily to the zerk. But I did remove the heatshield... it was needing a cleaning as well.