Here is a Service Bulletin Click Here. This information is provide Right Here at our Recalls/Service Bulletins Section
There are a couple others about the Steering unit. I know this is a problem, and someone that has changed out to a newer steering rack. GM does make a fix, so do a few of the aftermarket vendors. I think this is a problem all the way into the 1988 or 1989 Corvette.
Service Bulletin Number: 84-151 REIS
Bulletin Sequence Number: 005
Date of Bulletin: 8501
NHTSA Item Number: 76722
Component: STEERINGOWER ASSIST
Summary: GENERATOR AND POWER STEERING PUMP VIBRATION NOISE (MOAN) AT IDLE WITH A/C "ON "- REISSUED TO COVER ADDITIONAL PART REVISIONSFOR THIS CONDITION. CONDITION REPA IRED BY USING (3) NEW TUBULARBRACES AND FASTENERS TO REPLACE THE SINGLE REAR GEN ERATOR BRACE. ALSO REPLACE EXISTING POWER STEERING BRACKET WITH A NEW STIFF ER (RIBBED) BRACKET, P/N 14087559. 1984 CHEVROLET CORVETTE.
And I almost forgot... Welcome to The Corvette Action Center Community
This is the reason I replaced my rack and pinion on my 85
From what I understand the stock racks had an aluminum housing around and after enough time go's on the knuckles inside "warp" the aluminum and make it hard to steer off start up
The newer ones I guess use a stainless steel housing to prevent this from happening....So I did and it works great...but when I pulled it off MAN did alot of aluminum shards came outta the tubes along with diesel oil for power steering fluid LOL I guess those knuckles been wore out a LONG time Lol
Oh well at least I wont kick the fender when my power steering pump go's..... At Least I'll know why:eyerole Oh by the way check you Power steering pump Ive heard they do this symptom to