2016 XL Denali, Stiff Rear Shocks

[Brian Schumacher]

Hello, All. I have a 2016 XL Denali with Magnetic ride up front and the auto level air shocks in the rear. I've had this truck for about 3 years now, and recently its started riding like a skateboard. I'm pretty sure the issue is coming from the rear shocks. Is it possible for these to over-inflate? I noticed that my rear ride height seems taller than other XL Denalis I have seen on the road, with the same wheels, judged by the distance from the top of the tire to the the fender wheel opening. I put a new pump unit on it a few years ago. My pump runs and shuts off and I hear it bleeding off when sitting sometimes. I tried pulling the fuse for the compressor and after driving for some time, the level came down but ride got even rougher. I plugged it back in, compressor ran, ride got better and ride height seemed normal. After a week of driving, its stiff again and height seems high. Has anyone experienced this or have words of wisdom on how to proceed? Thank you

 

[Mando6point2]

If you have access to a good scanner you could do a trim level reset on the SCCM to see if relearning the normal ride height will fix your issue. may be an issue with one of the ride height sensors too and it may be commanding the pump on.

 

[CMoore711]

Some SUV owners with the MRC suspension have experienced the MRC shocks/struts going bad and getting stuck or “locked” in the max position and no longer able to function with any compression or rebound movement once this happens.

How many miles are on your Denali XL?
Have any of the shocks/struts been replaced or are they all original?

 

[Brian Schumacher]

Some SUV owners with the MRC suspension have experienced the MRC shocks/struts going bad and getting stuck or “locked” in the max position and no longer able to function with any compression or rebound movement once this happens.

How many miles are on your Denali XL?
Have any of the shocks/struts been replaced or are they all original?

Thanks for the reply. It has 102k miles on it now, although its been getting rough since about 90k miles. I bought it with 39k miles on it and have never put chocks on it. They appear to be original.

Any recommendations for replacement? Stay with active or go with passive replacements?

 

[Brian Schumacher]

If you have access to a good scanner you could do a trim level reset on the SCCM to see if relearning the normal ride height will fix your issue. may be an issue with one of the ride height sensors too and it may be commanding the pump on.

I have 2 code scanners, I'll have to see if I can access this on either of them.

 

[Dearmosd]

Any recommendations for replacement? Stay with active or go with passive replacements?

I personally like the Active only for the reason I have trailers that I use on grounds that are not level and find having the ability to let the air out to gain clearance help me a lot in a couple situations and ever after making my connection to the trailer having the rear shocks fill back up with air to get me back to the proper height is kinda nice for me.

 

[Brian Schumacher]

I put on a Genuine GM part over the weekend. Really not much more money than a passive shock so why change? I know maybe these wont last as long, but I made it 100k miles so I don't consider that to be a premature failure.

 

[Starheel]

I put on a Genuine GM part over the weekend. Really not much more money than a passive shock so why change? I know maybe these wont last as long, but I made it 100k miles so I don't consider that to be a premature failure.

riding good again? i am having the same issue i think?

 

[Brian Schumacher]

riding good again? i am having the same issue i think?

riding good again? i am having the same issue i think?

Yes. It had been riding like a dump truck for so long I forgot how its supposed to feel. Huge difference. Also, it ended up being a front shock, not a rear. I couldn't tell where the stiffness was coming from for sure so I stood on the running board on each side and started rocking in and watching the suspension move on the front and rear. Left front hardly budged. Bingo.