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Discussion Starter #1
Hey guys,

I have had my 2019 Chevy LTZ for 7 months now and it’s almost time to put my summer rims on. I moved up to this truck from an 2014 GMC SLT 2500HD. With that truck I cranked the torsion keys to level it, ran shock extenders with cognito upper control arms and the Pisk kit. My tires are 295/55/20 on fuel 20x10 rims with -24 offset. On the Sierra I did thr NorCal mod with the level to clear these tires.
I would assume with this Chevy they are going to rub, I would like to have the truck sit a bit higher, I removed the cognito ucas before I sold my other truck so I’m torn between throwing them in and going the same route as before of going with some sort of lift.
Is there anyway to buy guys longer knuckles for the front to avoid having to crank the bars? Most kits I have seen some with the UCA which I wouldn’t really need as I have them.
Any recommendations on a decent kit that won’t break the bank? I don’t want anything crazy high, maybe something like a 4” lift.
 

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Hey guys,

I have had my 2019 Chevy LTZ for 7 months now and it’s almost time to put my summer rims on. I moved up to this truck from an 2014 GMC SLT 2500HD. With that truck I cranked the torsion keys to level it, ran shock extenders with cognito upper control arms and the Pisk kit. My tires are 295/55/20 on fuel 20x10 rims with -24 offset. On the Sierra I did thr NorCal mod with the level to clear these tires.
I would assume with this Chevy they are going to rub, I would like to have the truck sit a bit higher, I removed the cognito ucas before I sold my other truck so I’m torn between throwing them in and going the same route as before of going with some sort of lift.
Is there anyway to buy guys longer knuckles for the front to avoid having to crank the bars? Most kits I have seen some with the UCA which I wouldn’t really need as I have them.
Any recommendations on a decent kit that won’t break the bank? I don’t want anything crazy high, maybe something like a 4” lift.
I have the Fabtech 4 inch performance suspension lift kit with the Stealth shocks and 35 inch tires on my 2019 Chevy 3500HD High Country. I believe my kit was around $2,200. Truck actually rides better now with the lift and tires than it did when I purchased the truck new off the Chevy lot.

Purchased my truck back in September 2018. Immediately put on a leveling kit that lifted the front end 3.25 inches, truly leveling the truck from front to back. The increased ride stiffness from reindexing (cranking) the front torsion bars was unbearable over time, and I also had to significantly cut the wheel well liners to fit 35’s underneath with only a leveling kit. Even added Bilstein 5100-series shocks to the leveling kit, which definitely made a difference, but nothing like switching to the 4 inch suspension lift kit. My leveling kit was made by Fabtech and came with aftermarket knuckles, so I was able to avoid the ball joint and tie rod connections from being at steep angles. However, this did not avoid the CV axles from being at steeper angles than I hoped for, even after I installed the 1 inch front differential drop kit. So I do not think taller aftermarket knuckles are available because they would exceed the maximum operating angle of the stock CV joints.

Since I stayed with a 18x8.5 positive offset wheel and do not have very wide tires, I was able to clear the front bumper, front valence, and the backside of the wheel well. Depending what leveling or lift kit and tire combination you choose, you may have to install spacers to move the front bumper out and trim the backside of the wheel well.

My recommendation is to go with the 4 inch suspension torsion bar drop lift kit. The ride comfort alone justifies this decision in my humble opinion. Hopefully my response gives you more information to make an informed decision.
 

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Discussion Starter #3
I have the Fabtech 4 inch performance suspension lift kit with the Stealth shocks and 35 inch tires on my 2019 Chevy 3500HD High Country. I believe my kit was around $2,200. Truck actually rides better now with the lift and tires than it did when I purchased the truck new off the Chevy lot.

Purchased my truck back in September 2018. Immediately put on a leveling kit that lifted the front end 3.25 inches, truly leveling the truck from front to back. The increased ride stiffness from reindexing (cranking) the front torsion bars was unbearable over time, and I also had to significantly cut the wheel well liners to fit 35’s underneath with only a leveling kit. Even added Bilstein 5100-series shocks to the leveling kit, which definitely made a difference, but nothing like switching to the 4 inch suspension lift kit. My leveling kit was made by Fabtech and came with aftermarket knuckles, so I was able to avoid the ball joint and tie rod connections from being at steep angles. However, this did not avoid the CV axles from being at steeper angles than I hoped for, even after I installed the 1 inch front differential drop kit. So I do not think taller aftermarket knuckles are available because they would exceed the maximum operating angle of the stock CV joints.

Since I stayed with a 18x8.5 positive offset wheel and do not have very wide tires, I was able to clear the front bumper, front valence, and the backside of the wheel well. Depending what leveling or lift kit and tire combination you choose, you may have to install spacers to move the front bumper out and trim the backside of the wheel well.

My recommendation is to go with the 4 inch suspension torsion bar drop lift kit. The ride comfort alone justifies this decision in my humble opinion. Hopefully my response gives you more information to make an informed decision.
Thanks for the reply, some good information for sure. Just a quick question about your 4” kit. I was looking at the cognito kit, it’s pretty expensive but one thing I noticed is they recommend buying the Cv drive line and trans bracket if going over 20mph in 4 wheel drive.
Is there anything that needs to be added to the Fatech lift to drive over 20mph in 4 wheel drive? Sometimes in the winter if the road is bad I run 4 wheel drive around 55mph.
 

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Thanks for the reply, some good information for sure. Just a quick question about your 4” kit. I was looking at the cognito kit, it’s pretty expensive but one thing I noticed is they recommend buying the Cv drive line and trans bracket if going over 20mph in 4 wheel drive.
Is there anything that needs to be added to the Fatech lift to drive over 20mph in 4 wheel drive? Sometimes in the winter if the road is bad I run 4 wheel drive around 55mph.
A proper installation of a single CV joint driveline requires the front axle to be rotated so it is a straight-shot (no angle) leaving the differential toward the transfer case. The front differential pinion connection is the u-joint end of the driveline and the transfer case slip yoke connection is the CV joint end of the driveline. This is the best design to avoid possible front driveline-caused vibrations. Since the distance from the front axle and the transfer case is increased with a lift, the replacement CV driveline is also longer to reengage more of the threads on the transfer case slip yoke. The taller the lift the more a longer driveline is needed to engage the proper amount of the threads on the slip yoke. As far as I know these are the two main reasons Cognito recommends adding a CV joint driveline to their lift design.

Fabtech obviously chose a different direction. The front axle drop brackets on my 4 inch lift actually point the front differential pinion slightly downward (2 or 3 degrees ? - cannot remember). They did this on purpose to make sure the front differential pinion angle and the transfer case slip yoke angle are the same so they cancel each other out as much as possible to avoid potential driveline vibrations. But since the front differential is not rotated to a straight-shot toward the transfer case, a CV joint driveline cannot be used on this design. One could add a slightly longer driveline for a 4 inch lift, but the slip yoke thread engagement distance on my truck is still sufficient so this would likely be a waste of money better spent elsewhere.

Personally, I am disappointed in the transfer cases GM still uses in these trucks, except for the new 2020 models. Autotrac should have been put in years ago to avoid the issues caused by the archaic part-time 4wd design. Notice that GM‘s Autotrac design includes a CV driveline, which surely avoids many of the vibration issues caused by the classic single u-joint driveline design, especially at steeper angles caused by lift kits. The Cognito trans bracket is simply required because of a clearance issue caused by the replacement CV joint driveline, which takes up more room than the stock u-joint design and would hit the stock shifting linkage.

I think I got all of this correct. If not, I am sure someone will correct me. Hopefully this assists by answering your questions.
 
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