So I normally don't do much truck work during the winter but I had to do some front end work. Fortunately I was able to work from home over the holidays and could get it done.

While underneath the front of the truck I decided to finally do the proper measuring of the suspension height. I'm a data-driven person and my forgetting to do this when I first installed the lift has been driving me nuts. Unfortunately, I did not think to do the measurements before I installed my lift so keep that in mind as I describe what I found.

Here are the measurements of my vehicle taken over the last few days compared to the official GM measurements, those used by Rough Country, and simple measurements of the distance from the lower lip of the fenders to the ground:

Official GM measurements:
measured Z-height: 5.5" (stock" = 4.6-5.0")


measured D-height: 5.5" (stock = 5.1" to 5.8")


Rough Country Measurements:
measured Front ride Height 19.5" (RC instructions: after installation of the 2.5" lift kit the new new front measurement would be about 21")
measured Rear ride height 18.8" (RC instructions: after installation of 2.5" lift kit new rear measurement would be 1" higher than before)


Height to lower lip from fender wells from ground (note I'm running 30/9.5R15 tires)
measured ground to lower lip of fender well: Front: 33.4"
measured ground to lower lip of fender well: Rear: 33.4"

Numbers aside, I know that the lift I installed did make a difference. Compared to before I installed it, afterwards, to get in the truck took a bit of a step up and similarly I could not as easily step out without sliding down off the side of the seat a bit.

As for what I did for my lift, it is described below. I did not install new torsion bar keys.

My stock suspension is the ZW7 "Premium Suspension Package".

The RPOs for the related components are:

• ZW7: Premium ride suspension (Nivomat self-leveling rear shocks with special lower rate rear springs, the shocks are supposed to do some of the lifting of the load in in addition to what the spring do to support the vehicle) (http://www.shockwarehouse.com/news/g...pensiondecoder.
  cfm)
• 6WH/7WH: Torsion bars with one of the lowest ratings for the maximum torque of 1,404 N-m (or lb-ft depending on your source) (https://nemigaparts.com/cat_spares/e...t/06/ts06-530/)
• FF6/FF7: Torsion bars keys, orange (actual specifications unknown) (https://nemigaparts.com/cat_spares/e...t/06/ts06-530/)

So my questions to people are:

Why is my truck relatively low even after doing the torsion bar crank and installation of 2" lift rear shackles?

Or more specifically:

• Were the torsion bars "sagging" along with the rear springs sagging before I installed the lift?
• Is the stock ride height of the "premium" suspension relatively low on purpose and I likely did add 1.5" to 2.0" to what was the original suspension height and therefore I should be happy with the current state of the lift? (This is where I wish I had made 'before' measurements.)
• Can I, because of my softer premium suspension, have more room still to lift the suspension by adding longer shackles in the rear and adding torsion bar keys that will allow me to crank up the front end a bit more (+0.5" to +1.0")?

 

I bet you were sagging before the lift. I know my rear springs are shot, I've got lift shackles in the back, and the rear still sits a little lower than the front.