I have 2005 s-type r, when I start it when its cold out, (below 35 deg) I'm getting a rolling clunk, for about 30sec, then it goes away, I've tried to narrow where it is coming from but can't isolate it. Maybe the SC. Any ideas?? It runs smooth as silk once I'm past the initial 30 to 40 sec or when its warm.

 

Tires can make sounds for a few minutes when there're cold!

 

Pretty vague description, can you expand? Does it make this sound with the car stopped or only while in motion?

 

just sitting, and it only does it for about 30 sec. sounds like it might be coming from SC, but I've never heard an Eaton do that before. It does not seem to be associated with engine temp either, because its not warming up, especially seeing how we have been running around 5 to 7 F. Its not like a rod knock either, it goes away way to quick. I got the stethoscope out but by the time I start the car and get out to try and find it, its gone. On restart its not doing it. Driving me nuts.

 

This may be an accessory belt driven entity other than the SC, perhaps A/C compressor. Does it make the sound with A/C off?

 

I would follow up on this. Remove one belt and start the car. Check for noise. Then remove the other belt. Start engine when cold and check for noise.

Takes some time but would answer if it's the SC or a pulley/tensioner.
.
.
.

 

excellent idea, now just need some warmer weather.

 

So this is a steady 'clunk-clunk-clunk' noise when the engine is running and warming up for the first 30-60 seconds of a cold start?

Does it go up and down with the rpm if you tap the throttle?

This is while the car is stationary, correcT?