MK4 IRS Alignment

[lewma]

Guys

Does anyone have a link to some instructions that show how to align the 2015 IRS in my MK4 ? I'm hoping I can tackle this on my own and get it close enough where I can eventually drive to a local alignment shop. Once the IRS is done, I want to align the front wheels too.

Just looking for some pointers.

thanks
mark

[edwardb]

Do you have alignment tools and have you done a front end alignment before? Because in simple terms the IRS alignment is similar to the front, just with one less dimension. Since the wheels don't steer, there's no caster to set. Just camber and toe. On the 2015+ IRS, these are adjusted with a threaded sleeve on the UCA and toe arm. Loosen the jam nuts, move the center adjuster, and tighten the jam nuts. The two settings (camber and toe) do interact with each other to some extent, so you'll need to go back and forth between the two until both are in spec. The other consideration is making sure the track is correct. The common DIY approach is setting strings outside the wheels/tires that are parallel to the frame. Then make sure the toe is the same on both sides, and the two sides together equal the spec. I personally use toe plates and a laser level/pointer instead of strings. But it's the same idea. If you're going to have a professional job done, don't obsess about it. Get the alignment close and it should be fine to get to the shop.

One other note. I don't recall if Factory Five has it in the IRS instructions. But it was on a technical update I received after taking delivery on #8674. FF recommends using red Loctite on the jam nuts and a witness mark to make sure they don't move. Something your shop should take care of when they're done.