Hi LR3NJ, first I lived just a couple of miles away from Princeton in Plainsboro. For 10 years, I miss NJ.
Thanks for getting back to me. Mine holds the gear just like you describe.
It's after I get out of my neighborhood and start driving on the county road at a constant 25 mph. That I observe my RPM bounce a couple of hundred RPMs.
If I attempt cruise control at this time the phenomenon is quite clear as I will eve feel a slight surge.
Let me know if you observe the same. Thanks

 

The bleeder hose is about 8.5mm ID so either 5/16" or 3/8" brass hose barb fittings will work as a repair kit item.

The smaller barb size slides easily, (perhaps too easily), into a new un-stretched hose so I would say that for replacement of the plastic T, that the 3/8" barb would probably be best. 3/8" is also easier to obtain.

You should also add a pair of suitable hose clamps to the repair kit rather than relying on reusing the existing ones.

The attached jpg's are from Green Line and Fairview and highlight suitable fittings. I chose the SAE coupler variety as the sealing seat is metal to metal and only two pieces are required rather than the three parts that I had looked at previously. I regard the fittings as a permanent fix as loosening the fittings allows the hose to be bled and then tightened back up. The appropriate fittings are highlighted in yellow on both pdf's.

Installing a new OEM hose assembly next time you flush the cooling system has some merit and might preclude all this field fix stuff.

Also the Tee is now available separate from the hose assembly as Land Rover part number LR027661; the complete hose assembly is Land Rover part number LR006158 where in all cases, the 0 is a zero.