Sorry man, I didn't know that no one had responded to your question.
You've discovered what is commonly referred to as "morning sickness", a low groan that occurs when cold.
Back in the 1980s, the early GM racks, along with similar racks from other vehicle manufacturers, often developed a problem known as "morning sickness." The steering would feel hard and stiff when a cold vehicle was first started, but normal power assist would gradually return as the vehicle warmed up. The problem was caused by wear in the spool-valve housing. The hard teflon rings on the spool valve wore grooves into the relatively soft aluminum housing, allowing pressure to leak past the rings. The cure was to replace the rack with one that had a sleeved housing or a cast-iron housing.
In 1988, GM began switching to racks that had cast-iron housings. This cured the morning sickness problem, which over time has reduced the demand for rack replacement. Even so, power racks are still subject to wear and to developing leaks. That’s why time should always be taken to inspect the rack when under a vehicle doing other repairs. The rack should also be checked anytime a customer has a steering-related complaint or the tires show signs of toe wear.
*Conditions to look for include steering play, poor steering return, steering harshness, loss of power assist, noise, memory steer, fluid leaks around line fittings or the pinion seal, or fluid in the bellows.
While this symptom usually disappears as the engine warms up, it’s a good warning sign that your car’s rack and pinion system could use a check up. A stiff power steering rack unit is a safety hazard, and should be replaced.
_ken
Power Steering
Linear Mode
