Hi,
Every once in a while the supercharger on my '06 XKR makes a howling sound (not the normal SC whine) and I wanted to know if anyone knows what that it is or has had a similar issue. It does not sound the the coupler issue that some people talk about. There is no noise at idle and most of the rest of the time it seems to run fine but once in a while it "howls" when I push it and is feels like the boost is reduced a bit. I have attached a sound clip that I patched together from a couple runs where I was able to get it to do this. The first few seconds are normal SC whine then at around 21, 26 and 33 seconds of the audio you can hear examples of the "howl". I have replaced the SC belt 4K miles ago. Could it be the belt or tensioner? Any ideas would be helpful. Thanks!

 

For what it's worth, I changed the SC gear oil in mine, and was pleasantly surprised with what seemed to be a little more power and less noise. Supposed to be lubricated for life, this is only about 7 or 8 ounces of synthetic oil and it needs to be vacuumed out thru the filler hole with a small tubing. The oil I decided to go with is Royal Purple Recip 100 which matches the OEM specs on my 2001 XKR blower perfectly and is available locally from my industrial supplier. It's very possible that the long snout on these superchargers possibly hamper proper lubrication on the outboard pulley bearing.

 

Thanks, Marc,
I'll check the oil and change that. I saw some other posts about the bypass valve not working correctly so I may check that out as well.

 

There was a bulletin for chirp noise on start up - the pulleys and idler bracket is supposed to be changed along with the belt, but its VIN specific, relating to all 4.2's.


It could be that when you changed the belt - which will not be stretched, is now causing more load on a bearing in the belt drive system?


I take it the noise is only present when engine is under full load?
+1 with Marc - maybe try changing the oil in the supercharger might help.


" Filled for Life " - Need to be careful with this statement. Treat it as " Filled for Life of Warranty ". This is merely a selling trick they use, but will only cost you more in the long run. Let's be honest, things wear out and break. If you keep the fluids changed, they will last longer. They say this about the transmissions, diffs, etc... You can still change the fluids in the transmissions and diffs if you choose to do so, wont hurt anything.


* Keep the fluids changed at regular intervals *


See attachment for bulletin info

 

Athiker81,

You should set up every 10 to 12,000 miles as the time to change the S/C oil...
which you can buy (around $15.00) per bottle @ your closest Chevy, Caddie or Ford Dealer...Ask for (2) Bottles of Supercharger Oil.....Also, go to Amazon or eBay and you will find Supercharger Oil changing kits for sale.....Buy one as they have the little tube and suction syringe....The Delco Oil is the Best.....This will keep your Supercharger nice and all quieted down......That whistling noise could be the Duct Seals leaking a little....Go to Eurotoys, LTD for these.....

Billy Clyde in Houston

 

Thanks, bcprice36! I have gotten the kit to change the oil and will do that shortly. I may try and take off the intake elbow so I can check the bypass valve as well. I removed the throttle body when I was doing some other work (replacing heater pump motor) and there was a lot of oily residue in the elbow but I could only clean it up so far in. I want to check and see if the bypass valve is gummed up or sticking. Anyone know if it is relatively easy to get the elbow and bypass valve off once I take off the TB? I'll take a look at those seals too.