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Discussion Starter #1
So about a week ago I bought a ‘15.5 Denali with 140K miles on it. From the pictures it looked like a stock truck suspension-wise except it has air bags on the rear leafs. Then I get the truck delivered to me and it’s on 35x12.50s on the factory 5 spoke 20” wheels. Done my share of digging around and figured out that’s not possible on stock suspension, but the truck isn’t level so I didn’t think anything had been done to it. Crawled under and it looks like it has stock keys with about an inch of space above them so I don’t think they’re cranked on, stock UCAs and doesn’t look like it’s up any higher in the front from what I can tell. Posting the pictures to see if anyone has any idea what’s done to it. I want to level it out because I hate the raked look but don’t want to go order a bunch of shit to find out something is already done I just don’t know about. Thanks for any help y’all have.
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If it’s leveled the ride will tell with stock shocks easily. If those are BFAT tires measure them I bet there not true to size, may be snow plow factory keys and tires measure actually 33.5 on the rim maybe 34. Are it has aftermarket keys cranked down a Lil. My truck will hold 295/70r20s with ease with 2 cranks. So who knows but the CV angles tell the story. This is just my opinion oh from my experience with my truck except I’m 3500 SW
 

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Yeah I’ve read the ride would be bad if it was, but this is my first 2500 so I’m not super sure what I’m looking for. My 1500 rode pretty hard so this actually feels nice to me😂 I stood my Toyo 33s next to the 35s on the truck and they were actually a little more than 2” taller than the 33s, so they’re cheap and loud but definitely 35s. I’m about 1.5” short of being level, so if I order a Cognito leveling kit for it with UCAs will it ride about the same?
 

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Crank your torsion bars get longer shocks are shock spacers. If you need upper control arms access the situation then, unless you just want a package deal. I have mine cranked 1.5” and bilstein 5100s for leveled trucks that are 2” longer and it rides near stock.
 

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Pretty sure the snow plow package is heavier springs, not different keys. When a spring was designed to control (not just make) motion, especially through a specific range of motion. it's right or its wrong, you can't just tighten it up. I found no difference in ride stiffness when I leveled my LBZ. Turning the keys does not make the springs stiffer, it only clocks the LCAs down a bit.

I agree with DRAelectrician that the angles tell the story. It was cranked up a bit or has keys.
 

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I have always heard there was green keys that was in the snow plow package not 100% sure maybe that was older models but he has tons of adjustment left in his keys.
 

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The whole point of a snow plow package is for the truck to remain within a range of the desired height whether you're carrying the plow or not. Torsion keys are no different than longer shackles on leaf springs. I'm sure snow plow keys are a common misconception because if you don't work with springs and truly understand how rate of torsion, or extension, or compression, and the cycle life works, most people will not figure it out for themselves.
 

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I also noticed the threads so I agree he has leveling keys. My LMM is 4500+ lbs on the front axle and no surprise, it was low. I cranked up the keys pretty far and I got the height back but they don't support the weight any better. Timbren jounce springs helped a lot. When going over a dip or speed hump the truck bounces like hell if you go to fast.
 

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Discussion Starter #10
Sounds good all. I will have to try cranking the keys this weekend and will get back on here and let y’all know.
 

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And just in case, I was not recommending you get Timbrens. It was just a reference about how you cannot adjust a spring to be stronger unless there is a restriction in it's travel. Like if you were to use short limit straps and crank it up until they're tight.
 

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I checked your pics one more time you have spacers on your shocks so you have a leveled truck with Aftermarket keys I would bet. If you crank much more your going to get stiff just make sure you mark the bolt and a reference point and count your turns. Jack it up crank it even turns and drop the truck semi fast off jack measure it drive it if you don’t like it crank it back down leave it alone. You like it take to get it aligned and tell them you raised it and hope you have a good alignment shop that will Toe it out and not use factory specs. Good Luck.
 

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Looks like about a 1/2 spacer on your shock.

I have a snow plow package and keys don’t look any different.

You may have aftermarket keys based on the amount of bolt you have showing.

You clearly are higher than stock based on rake and control arm angle.

New keys won’t help your ride.

New upper control arms may help a little.

Control arm angle is what matters for ride.

If you want 35s and a good ride, put a lift on. I tried a level. Now I have a lift. I should have done it right the first time.
 

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Sounds good all. I will have to try cranking the keys this weekend and will get back on here and let y’all know.
It won't be good for the CV joints. They aren't real expensive but just be aware, the more you crank it up, the harder it is on them. My LBZ is leveled with keys but it's not driven much. In 4WD, on road, there's a bad vibration up front from the angles. If I ever start driving it a lot again, I'll do a lift.
 

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Fullsize trucks use 1.75" hex and S trucks use 1.5" hex so the keys are not interchangeable
I knew there was something about colors because years ago I purchased a set of GREEN KEYs to put on my truck from years past. Ended up using some off a Ford I think I can’t remember.

15045171...4 degrees...Purple (stock 2500HD)
15657374...9 degrees...Blue (FK2 S10)
15603963...12 degrees...Orange (also S10)
15592573...14 degrees...Green (stock 1500)
15592574...18 degrees....White (Z85 suspension S10)
There is also a yellow key for the S trucks but I do not know the degree of index
 

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Congrats on the truck! It looks great man!!! I'll be putting 35x12.5's on my stock rims and stock height soon. It is very doable. There are a few threads about it on here.
 

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Discussion Starter #18
Thanks y’all, just seeing all the updates. Been a crazy week.
So the plan was just to level the truck but if the consensus is that it already has a level, I guess I need to go bigger because I hate the rake. I was planning on going with a Cognito kit to level it, but I could also swing a 3” Zone kit. Is that really any different tho since it just cranks the keys and swaps the UCAs and shocks?
 
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