GMT-800 2500 Upper Control Arm frame mounts spreading apart?

[emdece]

Hello all, first time poster here. I know there are quite a few GMT-800 HD / H2 guys here so I hope someone can help me out.

I recently bought some Upper Control arms from a well known company (not naming names until I figure out what's going on) that do not fit on my truck. Part numbers, fitment, etc has all been verified as me having the correct part numbers.

The issue is that the control arm legs are not spread far apart enough to fit in the mounting brackets. My stock control arms measure 12.5" (12-1/2) apart from the inside of the bushings, while these new arms measure about 12.25" (12-1/4).

I am being told that "Those older HD's are pretty inconsistent" in their frame construction. I have a hard time believing that GM would allow for this much variation. I am also having a hard time imagining that spreading the UCA pockets out 1/4" will not cause undue stress on the frame and arms over time.

The truck has never been wrecked and aligns perfectly so I do not suspect any frame damage causing this. The stock arms are easy (with a few mallet taps) to install and remove. The truck in question is a 2004 Yukon XL 2500 8.1l.

Any suggestions? Any help is appreciated!

 

[emdece]

It doesn't sound like much I get. If I saw this on any of the installation videos I would have no heartburn at all about spreading the mounts. All the YouTube videos I have seen show the new arms just sliding into place which is why I was so caught off guard.

I really appreciate the response. Anyone with any direct experience installing GM 2500HD UCAs that required tweaking the frame brackets?

 

[emdece]

Well, I did some more measuring and the outside-outside dimension of the arms (including the bushings, which are fully seated) is 16.50" on both.

It seems my problem is that the inside of the bushings on the stock control arms has been deformed / smashed over time. I'm going to play around with them some more tonight and see what I can find out.

Any other questions or suggestions welcome in the meantime.

 

[nitro_rat]

The flimsy mounts get crushed when you torque the bolts. Happens all the time. I spread them out all the time. No sweat...

 

[bigdogyj]

When I put the cognito arms on my 04 Yukon xl 2500 I also had to spread the ears open a bit. I don’t have exact measurements but a crescent wrench made it quick and easy. I don’t remember having to do it on my dually and these arms were pulled from my dually and rebuilt with new bushings and ball joints before installing on my Yukon. I just chocked it up to the old ones clamping the ears closer when they were torqued from the factory. You should be fine to spread them a bit to get them to fit. Remember not to torque them bolts until the full weight of the truck is on the tires. That way you don’t preload the bushings.


Sent from my iPhone using Tapatalk Pro

 

[lilkia]

You need to measure the width of the part of the control arm that houses the bushing, not the bushing but the metal. The new ones look wider than the stock arms. I would be very leary about a manufacturer giving me **************** excuses about "those older HDs being inconsistent". First the 2500 Suburbans and 2500 Yukon XLs are not true HD trucks and if they sold you parts for an HD truck that could very well be your problem. They do have a different frame and heavier duty components than the 1500s but they are not the same as the HD line of 2500/3500 GM trucks. Any manufacturer that gives an excuse like that either has a moron working the phone or sells a ************ product. You need to verify that those parts are specifically for a 2500 burb or for a 2500 HD Silverado dont assume they use the same parts.