D200 different pitman, draglink, or steering arm?
Posted: Wed Jan 03, 2018 6:50 am
Still working out the steering issues with my D200. This was a factory p/s truck, but I converted it to manual at least temporarily because the p/s is worn beyond repair. I ran into an issue, however. I bought a Moog DS653 draglink which is supposed to be correct for '61-'68 (it's the 13 3/4" link). I also got a 7 1/2" manual steering pitman arm from Bud Thorpe. When I put it all back together, however, the steering on the truck is wrong. For one thing, although the box has 6 1/2 turns lock-to-lock I'm only getting 5 1/4 turns between the steering stops on the axle (which are adjusted until the tires just barely don't rub the frame). Also, when the steering box is centered the wheels are not straight ahead, they point to the right a good ~5 degrees. You have to turn the box about 3/8 of a turn left to make the wheels go straight. At that point I end up with 2 1/4 turns to the left before I hit the stop, and 3 turns to the right.
Bottom line seems to be that something is wrong in the relationship between the box, pitman arm, draglink, and the steering arm on the left spindle (the curved one that connects the draglink to the left spindle). That or I put something back together wrong when I did the kingpins and leafspring bushings. Is it possible that being a D200 and/or a factory p/s truck that the steering arm attached to the spindle is different? If the steering arm were effectively 'shorter' (i.e. the attachment for the draglink were closer to the spindle axis of rotation) it would cause the same issues I'm seeing in my truck. For reference, my left side steering arm is about 9 1/2" from the backside of the spindle to the center of the draglink hole. Is it possible I incorrectly assembled the spindles in some way that could cause this? It seems unlikely this arm is bent, it shows no signs of impact and it's well protected from impact and very strong.
I could get a longer draglink to center the wheels, but that still wouldn't fix the fact that I'm losing 1 1/4 turns of steering box potential. The other common draglink for these trucks (Moog DS768) is 14 1/2" long and based on my measuring that would be longer than I'd need to center the wheels and would just push them to the other side of straight. Bud has a shorter pitman arm (6 1/4") that I think may do the trick, but I was wondering if anyone else out there has a manual steering D200 that uses a shorter pitman arm?
Also, I thought that the pitman arm should be at ~6:00 position when the box is centered. Mine, when the box is centered, is at ~5:00 (points a bit towards the rear of the truck). Is everyone's steering box like that?
Side note - I'm also wondering if this might be related to why some people have trouble with the CPP power steering kit. If some trucks use a shorter pitman arm for manual steering, they must have effectively a shorter steering arm as well (to preserve the overall travel relationship). If the CPP kit only comes with one length pitman arm, and is designed for trucks that originally had a 7 1/2" pitman, putting it on a truck that was designed for a shorter pitman reduces the mechanical advantage? If so, I'd like to figure out where else in the steering my truck is different (steering arm length perhaps?) and change that as well when I do a p/s conversion later.
Bottom line seems to be that something is wrong in the relationship between the box, pitman arm, draglink, and the steering arm on the left spindle (the curved one that connects the draglink to the left spindle). That or I put something back together wrong when I did the kingpins and leafspring bushings. Is it possible that being a D200 and/or a factory p/s truck that the steering arm attached to the spindle is different? If the steering arm were effectively 'shorter' (i.e. the attachment for the draglink were closer to the spindle axis of rotation) it would cause the same issues I'm seeing in my truck. For reference, my left side steering arm is about 9 1/2" from the backside of the spindle to the center of the draglink hole. Is it possible I incorrectly assembled the spindles in some way that could cause this? It seems unlikely this arm is bent, it shows no signs of impact and it's well protected from impact and very strong.
I could get a longer draglink to center the wheels, but that still wouldn't fix the fact that I'm losing 1 1/4 turns of steering box potential. The other common draglink for these trucks (Moog DS768) is 14 1/2" long and based on my measuring that would be longer than I'd need to center the wheels and would just push them to the other side of straight. Bud has a shorter pitman arm (6 1/4") that I think may do the trick, but I was wondering if anyone else out there has a manual steering D200 that uses a shorter pitman arm?
Also, I thought that the pitman arm should be at ~6:00 position when the box is centered. Mine, when the box is centered, is at ~5:00 (points a bit towards the rear of the truck). Is everyone's steering box like that?
Side note - I'm also wondering if this might be related to why some people have trouble with the CPP power steering kit. If some trucks use a shorter pitman arm for manual steering, they must have effectively a shorter steering arm as well (to preserve the overall travel relationship). If the CPP kit only comes with one length pitman arm, and is designed for trucks that originally had a 7 1/2" pitman, putting it on a truck that was designed for a shorter pitman reduces the mechanical advantage? If so, I'd like to figure out where else in the steering my truck is different (steering arm length perhaps?) and change that as well when I do a p/s conversion later.