Blown Rear Air Shocks on 2012 Yukon Denali – Is it Worth Fixing?

I have a 2012 Yukon Denali with blown rear air shocks and a "Service Suspension System" message on the dash. I’m wondering if it’s worth fixing and have some questions about what might be involved.

The compressor doesn’t turn on at all. Does this mean I’ll need to replace the compressor along with the air shocks, or is there a system feature that keeps the compressor off if it detects blown shocks?

My OBD scanner is giving me code C0660-06. Does repairing the shocks and possibly the compressor noticeably improve ride quality and smoothness?

Unless you’re planning to lift or lower the vehicle it’s not worth converting to non air assisted rear shocks. It’s going to ride ok at best on standard suspension. Plus you would also need to swap the rear coil springs out if you’re going to convert to non air ride. GM engineered these vehicles to ride incredibly comfortably on the Z55 suspension setups. It’s going to ride exactly as it was designed to with replacing with correct suspension parts.

If your air compressor is not cycling at each ignition cycle for 3-5 seconds, then it’s probably shot. Which is usually what happens when one or both air bladders mounted to the rear shock tears and then leaks. It’ll burn itself trying to keep the air bladders filled by constantly running and then die. Both OEM shock options, as well as the arnott brand shock options, which are the next best option besides OEM, can be had from rock auto for very inexpensive prices now, especially compared to how pricey they used to be.

I’d highly recommend you read through the MANY, MANY threads on the topic of Z55 suspension. They are located in the 2007-2014 subsection of the forum under the street suspension category. Or use the search feature and look for threads discussing the topic. All the info you will need, including the pros and cons of replacing shocks, both air ride and non air ride setups is all there.

I would recommend replacing both the rear air shocks and the air compressor. It is not a difficult task at all and the AutoLevel system definitely has benefits.

Keep in mind that your vehicle has two suspension systems, AutoLevel and AutoRide.

AutoLevel uses airbags and the air compressor to keep the vehicle level when loaded.

AutoRide adjusts the dampening of the shocks to accommodate different road conditions. Your rear shocks are part of both systems.

Arnott is my go to for the rear shocks. They have reman shocks that keep the full AutoRide functionality or new ones that use a passive method for adjusting the dampening, but also have circuitry to avoid dashboard messages for the suspension.

As for the compressor, Dorman and Arnott both make good compressors for this.

If you go away from the air bag shocks, you will need to replace the rear springs with a higher spring rate to make up for what the airbag was doing.

I think The 07-14 Denali has one of the most underrated suspension set ups for the size of the vehicle. Range/Land Rover can’t be touched for comfort but getting a YXL Denali close to a RR in comfort is a big deal.

Keep in mind RR has fully active, height adjustable air suspension all around. Denali has air and AutoRide height adjustment in back and AutoRide up front.

RR is hugely expensive on replacement parts. GM lowered the price of Gen III z55 & z95 struts as well as adding a lifetime factory warranty. That’s just nuts in today’s economy.

The only recommendation I’d make is purchase Arnott’s pump. It has a lifetime warranty and an overload protection circuit to keep it from overheating and dying. GM doesn’t have either. Arnott recently dropped their lifetime warranty and it’s only 2 years now.

I've had both passive aftermarket suspension components and the active Z55 suspension on my 07. I believe that the active Z55 suspension is far superior to the aftermarket passive system, but that is just my opinion, having experienced both suspensions.

As stated above, for the rear shocks, if you have a bit of wrenching experience, you can easily replace the rear shocks and compressor yourself.

For the front struts, you can also easily replace those yourself, IF you take the removed front strut assemblies and the new struts to your local repair shop and pay them to replace the old strut with the new strut, using their heavy duty spring compressor.

Thank you all for the detailed responses and insights—I really appreciate it! Based on your feedback, I’ll try to keep the AutoLevel system if I can find reasonably priced replacement parts locally. The OEM rear shocks from the official GMC repair service are priced at around $1,050 for the pair, and that’s before taxes. I also called them to inquire about the compressor, but they wouldn’t quote me a price over the phone.

So far, I haven’t been able to find Arnott or Dorman parts available here, but I’ll keep looking. It sounds like sticking with the Z55 suspension setup is ideal for maintaining the original ride quality, so I’ll focus on that as a first option.

Thanks again for all the advice and for sharing your experiences—this has been incredibly helpful!

Check over at rock auto.com. They’re a sight official vendor here and usually have sorts available for these rigs.

beeswax said:

Thank you all for the detailed responses and insights—I really appreciate it! Based on your feedback, I’ll try to keep the AutoLevel system if I can find reasonably priced replacement parts locally. The OEM rear shocks from the official GMC repair service are priced at around $1,050 for the pair, and that’s before taxes. I also called them to inquire about the compressor, but they wouldn’t quote me a price over the phone.

So far, I haven’t been able to find Arnott or Dorman parts available here, but I’ll keep looking. It sounds like sticking with the Z55 suspension setup is ideal for maintaining the original ride quality, so I’ll focus on that as a first option.

Thanks again for all the advice and for sharing your experiences—this has been incredibly helpful!

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Go to GMPartsDirect.com, enter your VIN, go to the Suspension section, and look for the exploded diagram of the front struts and rear air shocks. You should find what you are looking for along with the correct part number. And, the cost will be significantly cheaper than the local dealer, no more than $360 per OEM shock, with a lifetime warranty. You will also find the compressor there.