I made a new observation about my tick yesterday. I put her in park and manipulated the throttle by hand. The tick goes away at higher RPMs and when the engine settles back down it stays away. Tricky thing here.

 

The Shell Diesel formulations are good for flat tappet camshaft engines like the Rover V8. The 5w-40 is Rotella T6 Full Synthetic and is good to run all year long, albeit a bit expensive. The Rotella 15w-40 T5 is perfectly fine to run in Summer and will save you a bit of cash. I advise against running the 15w in Winter, however, due to poor cold flow at start-up.

 

If you are looking for tics. I had a bad one for a long time. Finally discovered it was the Fuel purge valve. google it and find it. Put your hand around it and you'll feel the tic plus it'll be quitter. It was a $30.00 fix. not saying thats your problem but if it is...you are happy.