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Discussion Starter #1
I have a 2018 CCSB 4x4 and will be leveling it in the future. I have looked and looked and everyone (for the most part) is saying the full level with control arms and everything. Suspension Maxx has the kit that includes Keys, and spacers for both shocks and differential. At that point, how much more of a difference would control arms be?

Sorry for the lack of knowledge, I came over from a Solid front axle Cummins.

Also, once leveled, will a 35/12.50/18 fit on the factory 18s? I’ve seem plenty of posts about them fitting with 20s, but wasn’t sure the offset difference between the 18 and the 20s.


Thanks in advance.
So far I’m loving my new L5P!
 

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Leveled trucks ride much better with aftermarket control arms. Like the Kryptonite control arms, they will offer better caster alignment angles compared to stock arms.
 

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Discussion Starter #3
Would running just the adjustable keys and shock and differential spacers still be a safe ride. Or would that potentially tear the front end up in the future? I understand the ride quality difference, just wondering how much of a difference there would be.
 

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My suggestion to you would be to get Upper control Arms, shock extenders or upgraded shocks, front diff drop spacers, & a drop shackle and set it a 1" if you want the level look. Most trucks with stock keys can get level going this route and clear 35x12.50s. I had my truck done like this for a while and i just did my buddies 19 with the same setup the other week. Anytime you go to level the truck by cranking the keys you are going to sacrifice ride quality, so i wouldn't jack the keys all the way up to try and match the rear when it is not necessary to clear the tires you want. The lower you can stay and still clear 35x12.5 the better you'll be IMO. Below is what i found to be a "budget friendly" list i ran and my buddy is running as well with 35x12.50. I would recommend the cognito pisk & tie rods as well if you can swing it.

Cognito UCA's- $513
CCM offroad front diff drop- $40
Mcgaughys drop shackle- $105
Shock Extender- $45
PISK kit- $240
DMAX store tie rods- $200
 

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Discussion Starter #5
Thanks for the reply! Excuse my ignorance, but what is a pisk kit?

Will the 35/12.50s fit the 18s without rubbing? Not sure of the offset on the factory 18s.
 

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The pisk kit is brackets for the pitman and idler arm under the truck that provide additional support and help with the steering/control of the vehicle, makes your steering feel tighter and helps with bump steer. You should be fine the only issue that might arise is rubbing on the frame in the rear of the fender at full lock. a 11.50 wide will solve that issue tho but i never try to lock my steering anyways.
 

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Also, be careful on the control arms if you are sticking with stock wheels with larger tires. People are having issues with Kryptonite UCAs and rubbing since they are bulkier than others.
 

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Because it is so easy to do, lots of people crank up their keys. Since they are cheap and everybody sells them, lots of people use lifting keys. Either one will mess up the suspension and make the truck less stable, less controllable and will wear parts faster.

The stock suspension is designed to change the camber so that the top of the tire moves in when the suspension extends and compresses. This keeps the tire contact patch in the same place so that the tire doesn't have to scrub sideways every time the suspension moves. When you mess with the keys it changes this action and the tires wind up skidding sideways a little every time the suspension extends or compresses.

If you only raise or lower the truck a little, say an inch, the effect is small but if you go much further it becomes more and more pronounced. If you try to raise the suspension to clear very large tires on over-sized wheels the cumulative effect will be negative for ride, control, safety and durability. That isn't to say that the truck will fall apart, break your spine or kill you the first time you drive it. It is a matter of degrees.

The good way to lift a truck is to cut off the original suspension and weld it or another suspension lower on the frame. If you do it right the engineering remains correct so that it works properly. This would be expensive though so few people do it.

The alternative is to swap in some aftermarket parts that reduce the negative effects of lifting. Among those effects are the location and travel of the ball joints. The UCA does not mount level on the frame. It is slightly higher at the front than it is at the rear so that when the suspension compresses the ball joint moves backwards a little. This increases castor and trail to compensate for the tendency of the truck to dive under braking.

A lifted truck with stock UCAs will have excessive castor and trail unless it is realigned properly but then it won't change the castor and trail as it is supposed to do. An aftermarket UCA can reposition the lifted ball joint so that it is in the right place with more normal alignment settings.

Additionally the stock UCA holds the upper ball joint so that it will have full travel in normal use. When the truck is lifted much of the extension travel is used up by the lift. The ball joint will not be able to bend enough to allow full suspension travel on a lifted truck. An aftermarket UCA will re-angle the ball joint so that it allows full suspension travel. The lower ball joint doesn't hit this limit until you lift it a bit further.

A better way to lift a truck is with new knuckles. You can get several inches of lift by having the hub mount lower in the knuckle. Then a couple of inches of lift in the tires and wheels and you may have all you need. Knuckles are not all that expensive.

I'm not recommending anything in particular but here is a kit for a reasonable price that goes with knuckles:

https://www.americantrucks.com/rough-country-35-suspension-knuckle-lift-kit-1418-4wd-silverado-1500-w-stamped-ste-chevy.html

That kit is for a 1500 so it doesn't directly apply but if you look you will find something that does.

The front axle shafts work best if they are level. Lifting the truck causes them to bend down a bit. The more you lift the worse it gets. The CV joints in the shafts have ball inside that transfer power from one side of the joint to the other. When the shaft is straight the balls hardly move but when it is bent they move a lot. The more they move the faster they wear.

CV joints have limited flex. It is sufficient for normal use but when some of it is used up to compensate for the suspension being lifted then there is less left for steering. What can happen is that the joint will reach it's limit in a turn and then you will go over a bump that either causes the wheel to turn a bit more or the suspension to extend further. The result of a joint in bind that is forced to go further is a multi-piece axle shaft that doesn't transmit power any more. The fix is to relocate the front differential so that the axles are level most of the time.
 

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Because it is so easy to do, lots of people crank up their keys. Since they are cheap and everybody sells them, lots of people use lifting keys. Either one will mess up the suspension and make the truck less stable, less controllable and will wear parts faster.

The stock suspension is designed to change the camber so that the top of the tire moves in when the suspension extends and compresses. This keeps the tire contact patch in the same place so that the tire doesn't have to scrub sideways every time the suspension moves. When you mess with the keys it changes this action and the tires wind up skidding sideways a little every time the suspension extends or compresses.

If you only raise or lower the truck a little, say an inch, the effect is small but if you go much further it becomes more and more pronounced. If you try to raise the suspension to clear very large tires on over-sized wheels the cumulative effect will be negative for ride, control, safety and durability. That isn't to say that the truck will fall apart, break your spine or kill you the first time you drive it. It is a matter of degrees.

The good way to lift a truck is to cut off the original suspension and weld it or another suspension lower on the frame. If you do it right the engineering remains correct so that it works properly. This would be expensive though so few people do it.

The alternative is to swap in some aftermarket parts that reduce the negative effects of lifting. Among those effects are the location and travel of the ball joints. The UCA does not mount level on the frame. It is slightly higher at the front than it is at the rear so that when the suspension compresses the ball joint moves backwards a little. This increases castor and trail to compensate for the tendency of the truck to dive under braking.

A lifted truck with stock UCAs will have excessive castor and trail unless it is realigned properly but then it won't change the castor and trail as it is supposed to do. An aftermarket UCA can reposition the lifted ball joint so that it is in the right place with more normal alignment settings.

Additionally the stock UCA holds the upper ball joint so that it will have full travel in normal use. When the truck is lifted much of the extension travel is used up by the lift. The ball joint will not be able to bend enough to allow full suspension travel on a lifted truck. An aftermarket UCA will re-angle the ball joint so that it allows full suspension travel. The lower ball joint doesn't hit this limit until you lift it a bit further.

A better way to lift a truck is with new knuckles. You can get several inches of lift by having the hub mount lower in the knuckle. Then a couple of inches of lift in the tires and wheels and you may have all you need. Knuckles are not all that expensive.

I'm not recommending anything in particular but here is a kit for a reasonable price that goes with knuckles:

https://www.americantrucks.com/rough-country-35-suspension-knuckle-lift-kit-1418-4wd-silverado-1500-w-stamped-ste-chevy.html

That kit is for a 1500 so it doesn't directly apply but if you look you will find something that does.

The front axle shafts work best if they are level. Lifting the truck causes them to bend down a bit. The more you lift the worse it gets. The CV joints in the shafts have ball inside that transfer power from one side of the joint to the other. When the shaft is straight the balls hardly move but when it is bent they move a lot. The more they move the faster they wear.

CV joints have limited flex. It is sufficient for normal use but when some of it is used up to compensate for the suspension being lifted then there is less left for steering. What can happen is that the joint will reach it's limit in a turn and then you will go over a bump that either causes the wheel to turn a bit more or the suspension to extend further. The result of a joint in bind that is forced to go further is a multi-piece axle shaft that doesn't transmit power any more. The fix is to relocate the front differential so that the axles are level most of the time.
I'm new to the 2500 world, but there sure doesn't seem like a lot to chose from when going the knuckle lift route with a 2500. Most seem to be 4"+, no?
 

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I just leveled my 2019 3500HD DRW. 1.5 inches by adjust torsion bars. Also installed bilstein 5100 1.5" taller shocks. It didn't effect ride quality and still has a slight brake. Looks great with stock wheels tires.
 

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I just leveled my 2019 3500HD DRW. 1.5 inches by adjust torsion bars. Also installed bilstein 5100 1.5" taller shocks. It didn't effect ride quality and still has a slight brake. Looks great with stock wheels tires.
About how many turns on the torsion bars was that (1.5")?
 

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About how many turns on the torsion bars was that (1.5")?
Mine was about 4 turns when i did mine, but each truck will be different. Best way to do it is to take your initial dimension from center of wheel to bottom of fender then adjust accordingly. Once you get it close go drive it around for a min then check dimension again to see if you need to adjust. make sure you jack the truck up tho when adjusting.
 

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I just leveled my 2019 3500HD DRW. 1.5 inches by adjust torsion bars. Also installed bilstein 5100 1.5" taller shocks. It didn't effect ride quality and still has a slight brake. Looks great with stock wheels tires.
I don't have any specs for the 2019 trucks but on my 2008 the factory spec allows for half an inch of change. Experience suggests that 1" never causes a problem. Depending on how sensitive a person is perhaps a 1.5" torsion bar lift would still be neutral. It's when people go for 3-5 inches of lift in the front that things get out of hand.

However there are people who claim that they can tell a difference with even an inch up or down. I had a Nissan with torsion bars years ago. I lowered it 2 inches and the ride was seriously compromised. I kept it that way for several years and when I put it back to stock I was amazed how much better it felt.

I have no position to mandate how anyone plays with their suspension, thank goodness. I advise people to make informed decisions and then be happy with them.

I guess it all depends on why you are messing with the suspension but it seems to me if you spread the changes over multiple methods you are least likely to get into difficulties. An inch from tires, an inch from torsion bars, an inch in the body, etc.

People used to like high rear ends. I had a neighbor who lifted his Mustang until it road around with maxed out shocks most of the time. I thought it was a big mistake but he thought it was great. Today there doesn't seem to be any consensus what is good and what is bad. I guess that is a good thing. I just want people to know what they are doing when they mess with their suspension.
 

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I just "leveled" my truck (in quotes because the back is still higher despite cranking the hell out of my keys) using aftermarket keys and shock extension brackets. When I first installed the keys, I had it set at maybe 1.5"-2" of lift. The ride stiffened up, but in a good way. Less bouncy and my steering felt more firm also. It was great.

However, I like tires that hang halfway out past my fenders so I had to crank the keys up to about 2.5" of lift to avoid hacking up my bumper. At this point, my ride is very stiff and my right control arm is almost sitting on the bump stop (the droop limiter on the frame). Oddly enough, my driver's side has plenty of clearance even though I measured both sides of the truck and they are the same.

So in conclusion, if you plan on going past 2" I would recommend the aftermarket control arms, and also keep in mind you are going to sacrifice some ride quality from having the bars cranked up that much.

The other thing I wonder, is what about the steering angles coming off the gearbox? Is there no way to compensate for those when we lift/level? And if not, does it matter?
 

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I have a 2018 and have turned up my torsion bars just a small amount (which I needed to help clear tires) but I would not want to max them out due to ride quality. I am also getting ready to buy UCA's and tie rods so I know that stuff is not the cheapest but as others have said its the only real way to go (especially if you will be towing in my opinion)
 

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I'll be using the RC 3.5" kit to lift my 2019. I am adding aftermarket tie rod ends as well... I've used this kit on my 2013 w success... It has 1.5" blocks in the rear, and I don't crank the new keys fully to keep a rake as I tow often...
 
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