My steering wheel has been loose with play for about 3 years now. I have replaced everything there is to replace regarding the steering. However, when I did the gearbox I called a mobile mechanic to help me screw the hoses back into the top of the gear box I explained to him that even with the new gear box in it still had play. He told me that on the older Chevy and GMC trucks they have a “steering pin” (I’m assuming at the wheel) that tends to wear out and cause the symptoms my truck was having. Unfortunately I got a new phone since then and lost his number. I wanted to see if any of the seasoned mechanics on this forum could tell me what he might have been referring to. Thanks ahead of time for your help.
Obviously you didn’t replace EVERYTHING. List everything that you did replace and let’s see who can be the first to name what that PIN really is called.
Are you sure he didn’t say the “pinion” wears, as in “rack and pinion”? Have you changed the rack?
Follow Rod’s suggestion. List what you HAVE done and we can figure out what’s actually left.
The 98 GMC Sierra doesn’t use rack and pinion steering.
It uses a steering gear box.
So far I have replaced:
Power Stearing Pump (went out on its own and was replaced)
Everything within sight under the truck seems airtight. This is why I would think it would be something north of the drive shaft and near the actual steering wheel if that is possible. My knowledge in this area is very limited.
Do you mean tie rod ends?
Did you check for any play at the lower intermediate steering shaft where it connects to the steering gear?
The idler arm on your model is sold as 2 seperat pieces. Were both replaced?
There’s something called a king pin used on some steering/suspension systems. Not sure if it applies to yours though. I think king pin designs are not commonly used these days.
I checked and don’t see the Sierra listed under GMC truck for that year. Maybe you are outside the USA? The GMC K3500 vehicle does have a king pin design, so maybe yours has one too. If so, maybe that is the “pin” he’s referring to. A loose king pin can affect steering performance.
These were replaced with ball-joints many years ago.
The Sierra was just GMCs name for their pickups, The name was used on the 1500, 2500, and 3500 models.
GM part number 12472161, priced at $102.60, referred to as a “king pin”. For a 1998 GMC Truck K 3500 Truck 4WD V8-454 7.4L . Maybe the term is used differently these days though.
Check this part on the steering shaft. If that joint at the far left in the picture is bad it needs to be replaced. This could cause the problem you are having.
King pins are still used on large trucks. Ford Twin I-Beams continued to use king pins until the mid 80s I believe. But the term ‘king pin’ is used as a reference when describing steering geometry. King pin inclination is used to determine proper steering geometry despite the lack of a king pin in the suspension
Ford STILL uses twin I-Beam front suspension
Check out this video. I have adjusted many Saginaw steering boxes and never had a problem. Just have someone move the steering wheel back and forth while the adjustment is done. “Finesse” is the key word here. The steering box will wear out quickly if the adjustment is done too tightly.
@Tester writes …
King pins? These were replaced with ball-joints many years ago.
Tester, do you continue to stand by your statement above?
The OP stated that they replaced the BALL JOINTS!
So the vehicle can’t have KING PINS!
Don’t you read these posts?
From what I can see l… now I admit this is just a wild guess, probably totally off base, dimwitted am I … but my wild guess is that a 1998 GMC Truck C 1500 Truck 2WD V8-5.7L VIN R suspension uses king pins.
A 1998 GMC C3500HD class 4 truck has an I-beam front axle with king pins
A 1998 GMC 1/2 ton pickup truck , such as OP’s truck, has upper and lower a-arms and upper and lower ball joints . . . the kind where the rivets get drilled out