99 Tahoe, Front end alignment "knockouts"

[kman]

My wife took our Tahoe to the local auto dealer for a front end alignment. I told her if there is any questions just have the dealership call me. Well, the call I expected came. This is where it gets interesting.
They claim in order to do the front end alignment they would have to remove the original factory knockouts in order to do the job. Around 300 bucks should cover it.
I have never heard of knockouts that have to be removed to do a alignment, but I'm not a mechanic either so I just dont know.
O.K, now this were it really gets interesting (still with me)? The vehicle was involved in a nasty collision 3 years ago with the right front axle taking a pretty bad impact. The right A frame was destroyed and had to be replaced. The aluminum mag was shattered and the frame had to be straightend,you get the picture right?
Here's my question, with the vehicle taking such a major impact to the frontend 3 years ago, How did they do a front end alignment then, with these so called knockouts still in place? Whats going on here? Ken

[JDP]

I'm not a mechanic, have a owned a tahoe and a Suburban but have not heard of this before today. I found this info below....I'm sure GMC Jon will respond once he sees your post.



" These are little punchouts in the upper control arm(UCA) mounts on the frame. From the factory, offset washers are attached to the UCA bolts at the frame(Some poeple refer to these as "cams" because they make the control arm move back and forth similar to the way a "camshaft" makes a lifter move). That is how you adjust caster and camber on this vehicle- by turning these "cams" in or out to change the alignment. Now from the factory there is just a hole in the mount that these cams are in. You cannot turn them because there is no slot for the bolt to slide in. This is where the knockouts come in to play. In order to adjust the alignment, you need to remove the "cams", slide out the control arm, and viola, on each side of that hole in the frame is a "perforated" (I use that term lightly - some can be a bear to remove) outline in the steel. You need to use a special tool, air chisel, or in the real "bear" cases, a torch to remove the punchouts. What this does is take a 1/2" hole and turns it into a slot approximately 2" long, allowing for the in and out movement for adjustment. There are two of these on each side of the vehicle for a total of four knockouts.
If anybody with one of these vehicles had it aligned with these knockouts still installed....well you got a "toe-set" not an alignment-you can't adjust what you can't move."


Hope this helps,

JDP

[Terroreyes]

Even if it is legit, NEVER send a woman to get auto repairs. There's been several times my fiancee got a quote on a repair, then I got a quote or called them out and they were up to 50% different. Recent example. I had her call to get a price for tires on my truck while I was at work. Didn't even take it in. They quoted her $180/ea. Didn't get around to it until later in the week. I called to see if they had them in stock. Gave me a quote of $130/ea!

[yarcraft91]

Hmm. I've taken all my Chevy trucks to our local Midas Muffler shop for alignments. They've never said a thing about knockouts, they always adjusted toe-in/camber/caster and the price was always much less than $100.

I'd think removing the knockouts for first alignments would be averaged into the overall cost of alignments done at the shop. Charging separately for the knockouts sounds like a dealer-profit-improvement program, which you might imagine new car dealerships wanting these days.

Given the damage repaired on your Tahoe, unless your tires have worn very badly, assume the front end was completely re-aligned 3 years ago and if there were knockouts they were removed back then. At any rate, removing 2 knockouts, whether by air chisel or torch, doesn't sound like a job that would take $300 in labor- unless the shop does the work with a Dremel tool.

Take your Tahoe to an independent alignment shop- they can do just as good a job and will probably charge less.

[perchjerker]

really depends. I have worked at Midas shops, dealers, etc.

If they can adjust the toe and the camber and caster are in spec, they wont touch the cams or remove the knockouts. Why create more work if its not needed? Many times on these vehicles its just to toe that is out of spec, or as we used to say "set the toe and let it go"

Also, its not just a matter of chiseling them off. You have to remove the control arm nuts, etc to get to them.

Its been years and years since I have done this, but its not as easy at it might seem like Dodge stated in his detailed description.

As far as the truck being in the crash, yes, this does sound suspect. I would think that the knockouts would have been removed somehwhere along the line but they could still be there

this is not done as a profit center for the dealers. They do this at the factory to make assembly faster and more accurate.

[yarcraft91]

PJ:

If you've worked in shops doing alignments, you would know more about this than I do. I can say that I always call ahead and ask the price of an alignment, have never been asked if this is the vehicle's first re-alignment. I've seen the new shims in the suspension, so I expect caster/camber were adjusted.

I expect the knockouts are a factory assembly cost-savings step, not intended to increase later cost of service. Why would any company want that kind of black eye? I'm reminded of the Chrysler cars in the mid-70's that had no grease zerks on the front suspension- remember those? At the first lube job you had to pay the shop to install them and the cost varied widely.

[perchjerker]

well if you have shims then you dont have cams, or the knockouts.

so that answers that question...

totally different setup