Posted by Vaughn [108.162.215.169] on Wednesday, August 26, 2020 at 14:20:53 :
In Reply to: Re: Better Way posted by mannyc [162.158.63.209] on Wednesday, August 26, 2020 at 12:47:25 :
The part number for the knuckle screws (C-180177) cross-references to the Military Standard 90725, Grade 5 screw, that's all I have to go by, but I could be wrong. The knuckle recessed in the steering knuckle does give it weight and turning strength when moving that could be why grade 5 was considered enough, but not enough at a dead stop turning right or left putting strain on the knuckle screws something they may not have been designed for.
Run a tap through the castings to see if you get a lot of shavings that might indicate deformed threads. If you upgrade the screws get as much thread surface in the knuckle for the screws as you can.
If you do go for grade 8 or 9, and you still have the issue, then you should consider exploring 9/16 screws.
Also if a W300 uses power steering with close knuckle Dana 44, look into the size screw for the knuckle/spindle as something to compare to.