MkVI GTI subframe shift ??

I hit a pothole in my 2011 GTI hard enough to get a bulge in the right front tire's sidewall (fortunately the rim was still ok), so I replaced both front tires with same brand /model already on the car, putting the new tires in back and moving those on the back to the front. Since then, the front end "hunts" around at freeway speeds. I took the car in to tire shop for a 4 wheel alignment, thinking that I probably knocked the toe out of spec. Alignment rig showed instead that toe was in spec, but left camber was - 0.18 degrees (side not hit) and right was - 1.70degrees. Spec for front range is - 0.23 to - 1.23 drgrees (nominal being - 0.73). Diagnosis is the front subframe shifted. Fix required is an unbolt and iterative shift of the front subframe until camber is back in spec on both sides. There is no visible damage to anything underneath the car (me, the tech, and the manager all looked while it was up on the rack).

Question is this ... have any of you guys run into this before on a fully stock, never crashed ever car, that mearly hit a pothole? Granted, the hit was enough to baloon the 40 series tire's sidewall, but jeez ....

If you hit a pothole hard enough, it IS a crash.

Rear sub frames in Xtypes have this same problem. Serious pita to get back in spec.

The subframe is designed to be shifted as part of an alignment, so it's not unreasonable to expect it to shift in a tire bubbling pothole incident.

A number of companies make subframe bushings that will lock it in place, useful if you have camber plates.

In reply to red_stapler:

Now that the original "I broke my car" panic has worn off, I am seeing that shifting the front subframe on a MkVI Golf is the only factory way to adjust camber, vs. the previous method of having eccentric bolts on each front strut. From my perspective, this seems to be a crappy system, VW.

I haven't done it myself but I've fixed a buch of cars that have had that happen.

So it's still an alignment, just different method than you expected. It's probably no more expensive than getting a bent rim fixed - which is the usual Audi/VW recipe after a big pothole adventure.

I'd consider myself lucky to not be chasing bent rims if I were you.

einy wrote: Question is this ... have any of you guys run into this before on a fully stock, never crashed ever car, that mearly hit a pothole? Granted, the hit was enough to baloon the 40 series tire's sidewall, but jeez ....

All the time. Don't be surprised if there isn't enough allowance to shift the subframe back into shape, either.

That said, a degree of cross camber shouldn't cause any kind of hunting, it should just drift to the side with the most positive camber. Swap tires front to back and see if it gets better, one of your old tires may be bad. Further point: I usually see large VWAG wheels crack when hitting large bumps. If your wheel isn't cracked, you didn't hit the bump very hard, so the alignment issue was probably there all along.

Hits usually affect caster, anyway.

Also, what is "in spec" for toe? Just because it is in range doesn't mean it will drive very well.

Are 40 series tires stock?

In reply to dean1484:

225/40R-18 is the stock size.

In reply to Dashpot:

I was VERY happy to see near zero runout on the dial indicator when I spun that rim. Quite surprised, given the severity of the hit.

Wife and I were going out to dinner in Covington, KY and I hit the pothoke on a surface street just before parking. I recall telling her that I'd be surprised if the tire wasn't flat when we got back to the car. It wasn't, and no bulge at that time either was visible. The bulge took a couple of weeks to show itself, oddly enough

In reply to Knurled:

Front toe currently is 0.08 degrees toe in each side. Spec is 0.00 degrees to 0.17 degrees toe in each side, so right in the middle right now.

I had alignment checked 19k miles ago when I put that set of Pilots on, and all measurements were near the middle of spec, so the pothole hit absolutely changed things. I am the only driver if this car, so I'm confident nothing else was hit between then and the present day.

All that said, I sure hope there is enough range of subframe movement available to bring things into alignment without having to add camber plates, etc. All in all, a **** design by VW as I see it to have this method as the only factory way to adjust front camber.

einy wrote: All in all, a **** design by VW as I see it to have this method as the only factory way to adjust front camber.

Eh, by doing it this way, you're a lot less likely to need to adjust camber in the first place. Because of the way forces are applied, the subframe is a lot less likely to shift compared to a crash or cam bolt on a mac strut.

The fix for the jag was to get Volvo upper control rods that were adjustable. I also needed new bushings in the jag rods and it was cheaper to get the Volvo parts than OE jag parts so it was a double win for me.

I had no idea that those came with 40 series tires.

When I bought the car I asked if the dealership would swap wheels / tires with a TDI, which are 50 series on 17" rims. They said they would if the buyer of their one TDI on the lot wanted to, but he didn't. I mostly just liked the style of the TDI wheels better than the GTI's, but the extra sidewall height on a daily driver on Ohio roads would have been a bonus.