1996 Shifting Vibration

[pstapler]

I have a 1996 Explorer XLT V-8 2WD. Under normal driving conditions, it has recently started vibrating when shifting into OD. The vibration only lasts for 1-2 seconds and is similar in nature to driving over rumble strips. I have manually shifted the truck from 2nd to drive with the OD turned off and with the OD turned on and the vibration does not occur.

Any thoughts?

Thanks,
Patrick