And here's part two...
Since it had been several days and I'd not heard from Chris on either email or phone I sort of assumed that I'd been dropped like a hot potato by builder number two. That wasn't the case - Chris did reach out to me several weeks later but at that point I had turned the van around and went back to the shop and had them pull the entire kit off and put it back to MG's set up.
Let's call that a failed $2700 experiment. If you add that to the parts and labor spent chasing this for the past year I'm at about $9000 trying to fix my van. Or about the cost of the Volvo wagon I should be buying my wife.
I spent a lot of time thinking about this issue, laying on my back under the van and on the phone talking with Leonard. My theory is that the radius arms are not being held in alignment to each other. If you look at my video you can see the axle moves in an arc around to the middle of the axle. Not side to side which is what the track bar prevents. The parts that hold the axle to the van - the only parts that hold the axle to the van - are the radius arms. This is a very different set up than leaf springs which hold the axle in four points - two in front and two behind the axle which offers a lot of rigidity. Radius arms, in contrast, are held in only two places to the frame, behind the axle and have bushings in them and bushings flex. If there's a "moment" or an instance that upsets the axles linear alignment to the body those forces feed through to the radius arms and into the frame.
Leonard agreed that the theory made sense and suggested that I order aftermarket bushings of a higher durometer to help eliminate flex and perhaps prevent that "moment" from occurring. He also suggested that I install a double steering damper to control and prevent the propagation of any shimmy until a solution is found. To be fair that was MG's suggestion that I didn't want to accept but I'm tired of fighting this and replacing parts. So...
So I purchased a Fox double damper set up as it's the most beefy option on the market. We installed it and then I headed to Ron's Front End for another alignment.
The head mechanic there was extremely sympathetic as he'd just spent 6 months trying to resolve the exact same problem on a brand new F250. He liked the conversion of my van as it was set up and he checked everything and it was all in spec and he liked the way it drove. He, like Leonard, didn't charge me at all for their time.
So is it fixed? Depends how you look at it. Is it better? Yes.
Downhill hitting the brakes between 45-55 you can feel the slightest of vibrations but the van no longer exhibits a full death wobble. I can now tow with peace of mind and I'm not scared to go down mountain passes or take my family on trips. Do I feel like this solved the problem? No.
What I've learned over this past year or so is that the design Ford uses and that MG's kit mimics can be prone to this behavior. It is much more likely to affect V10's and diesels like mine and Taylors' van and that's because they're heavier. The frames of the vans are not the same as the frames of the pickups and the added weight invites issues. Even new pickups can have these problems. The other thing is that for the front end to perform as designed
every single part of the steering, suspension, front end, alignment, tire balance and pressures need to be brand new and in spec. If you put a used axle in your van you're asking for trouble. If you repair one part at a time each worn part invites the specter of wobble and once you have this issue it is devastating to the rest of the parts in the chain. Trust me on this.
My theory and the thing that I want to change is the radius arm bushings. We put new bushings in but it made no difference because the stock bushings are of a lower durometer. I have a friend who manufactures custom bushings and I'm talking to him about making custom ones for the van as there is no aftermarket for the newer axles - only stock replacements. Not even Moog makes them because the axles are too new to warrant the cost of tooling startups according to Moog's head of development who I spoke to at length. My friend looked at the stock bushings and suspects that they are in the 65-70 durometer range and he thinks that an improvement could be had by going up to something nearer to 80. That's one option I'm considering.
The other aspect that I feel could be an issue is that the radius arms do not tie into each other. I know from my many years of motorcycle racing and building that the relationship of the headstock to the swingarm pivots is essential. Any movement, any flex invites unintended steering. There is next to nothing tying the frame rails
to each other and, by extension, keeping the
radius arms in alignment. I would like to make a cross brace that would tie both radius arms together in alignment. This is essentially what I did to my BMW road racer frame and it worked very well.
I don't know why this issue hasn't been solved in the larger sense and I'm certainly an unlikely person to solve it. What I do know is that I'm curious, a pretty good problem solver and too stupid to stop now. I don't think that three steering dampers on my front end is what I'd call a "solution" but lots of people seem to think it looks really cool...
So, not sure if that was the update you were looking for but it's the update you get. I don't really accept that this is an issue without a solution so I'll continue to beat my head against a wall... er, explore ideas and report back what I find.
And so this doesn't get derailed I have some other things I'm working on that I'll update tomorrow.
Gregor
PS - in other news you'll see that I have Oregon plates now instead of VT. I also have an OR title as well. Thanks VT - you rock.
j/k
