consequences of a 1.5" level lift on a sierra/silverado 1500

[Donstar]

I am looking for an explanation as to how a front 1.5 " level impacts your truck. I love the "lifted" look with a slight rake for carrying the odd load. I currently have 255/70r/17 tires and will not be going any larger than a 265 so I know I don't need a "lift". I have read and participated in the huge thread about leveling on this forum but somehow I haven't enough information to make the move. I understand that installing a spacer at the bottom of the front shocks is the most cost effective way to lift but what are the trade-offs? Do I lose 1.5"s of suspension travel? I have heard it makes no difference. What actually happens to create the lift? This is purely a modification to enhance the looks of my truck but I don't want to do it at the cost of losing function.

[robvas]

You lose some suspension travel and will need the truck re-aligned. Also your suspension will always be a little bit 'over extended' compared to where it would normally be, so it may wear slightly faster.

 

You know when you jack your truck up the wheels come down a little bit as the truck goes up? That's all your doing, is pushing the truck UP or pushing the control arms DOWN, depending on how you want to look at it.

[robvas]

[Last C5]

I used the 1.5" lift of the Bilstein 5100 shocks and a small shim to get a full 2" lift in the front. I added the 1" taller block that comes with the Firestone Air Bag kit to lift the rear an additional inch and I think it rides just fine. The slightly stiffer front end actually makes the truck handle better.

[Donstar]

Thanks for your response. A spacer will reduce my up travel and increase my down travel? Wouldn't one cancel out the other? The suspension's response to a pot hole should be the same, using my limited understanding!

[ECOBUSTER]

Your length of travel will be the same with a spacer. The range of travel will start x" lower and end x" lower. Just think of your control arm/spindle setup as one mechanism that travels up and down. Then a strut in the middle with a certain amount of set travel. The spacer just changes the angle of the arm/spindle down a little, while the strut is doing its usual work. This provides the lift. So compressed or not the arms will always be at a slight down angle.

 

Just FYI, I was going for a similar stance and installed 5100's set on the third notch (1.25"). Drove around a little with p-metric tires and the truck rode better then stock. Even with load range D 33" tires the ride is good. Still soft enough but everything feels tighter. Less lean and more stable.

[Donstar]

Great explanation! Thank you. I'm getting a common message from all of these responses that Bilstein 5100 is the preferred way to achieve my goal. You all are obviously very knowledgeable on this topic and have chosen the Bilstein's for your vehicles!

[amxguy1970]

A good read on the Bilstein subject. A note on those, if you set them high they pre-load the spring and will ride rougher. The Bilstein shocks are better tuned for the raise and may help in certain full drop situations and protect the ball joints more but they are still susceptible to premature wear as well as the normal CV, end links, ect.

 

http://www.tundrahea...0-leveling-kit/

 

Good luck and post pics. A 1.5 is what I will put on and probably do a 1 inch rear as well, not looking to so much level as raise overall a little while keeping rake since I will be towing and hauling with it (mine wasn't too bad, along the lines of 2 inch rake), so once all done I will still have between 1.5 and 2 inches of rake. Plus that helps protect the suspension more than the 2+ inch kits.

 

Tyler

[Spurshot]

Moving the spring perch up on these shocks a fraction of an inch does not change the spring rate when the truck weight is supported by the spring. It simply moves the sprung chassis up. The ride quality change is due to the change I the angle of the suspension A-arms. Using a spacer (top or bottom) or cranking the spring perch up on an adjustable height coil over assembly will result in exactly the same ride quality change (same increase in stiffness) if exactly the same spring is used to raise the truck exactly the same height.

Edited February 13, 2016 by spurshot

[Donstar]

Good link, Tyler! Thanks! I was wondering myself if the explanation by Bilstein may be a little skewed as they do have a product to sell! Levelling shocks must impact the up travel the same as a top spacer. Their increased shock length logically should increase down travel which Bilstein says is a negative with spacers.

Spurshot, I appreciate you responding. Your experience with these trucks is impressive! I wrote GM for their recommended method of "levelling" and they were firmly opposed to any such modification. (No surprise-but worth a try) My parts guy at the dealership recommends the ready-lift split system. This would be too high for my liking and I don't know if a split system would double the problems or cut them in half !!

Edited February 13, 2016 by Donstar

[Donstar]

Moving the spring perch up on these shocks a fraction of an inch does not change the spring rate when the truck weight is supported by the spring. It simply moves the sprung chassis up. The ride quality change is due to the change I the angle of the suspension A-arms. Using a spacer (top or bottom) or cranking the spring perch up on an adjustable height coil over assembly will result in exactly the same ride quality change (same increase in stiffness) if exactly the same spring is used to raise the truck exactly the same height.

I have read that one of the benefits of a front level is to compensate for sagging from heavy bumpers etc. This got me to thinking if different springs are used for different engines. There must be considerably more weight to a 6.2 than a 4.3. I can't tell which motor is in the vehicle by the amount of rake. If this is the case, then could lift be generated by heavier springs? I assume that if this was the case, it would probably be an expensive method and hard to predict how high the lift will be until they are actually installed.

[robvas]

I have read that one of the benefits of a front level is to compensate for sagging from heavy bumpers etc. This got me to thinking if different springs are used for different engines. There must be considerably more weight to a 6.2 than a 4.3.

It's only about 100lbs difference. I remember a crate LS1 weighing like ~450lbs. A 4.3 would weigh about 3/4 of what a V8 weighs.

[Donstar]

Top or bottom spacer or Bilstein's elevated spring mount, if I understand, all do basically the same thing. The suspension travels, drops and rebounds the same distance while the nose of the truck sits higher. Bilstein shock absorbing qualities may be superior to stock but as a method of leveling they have the same effect on suspension travel as spacers. Is it not more reasonable to look at leveling as more of a body type lift as a way of understanding? A level kit is pushing the body further off of the ground through reducing space for the spring. The increased pressure from the spring is pushing the body upward. The suspension and wheels aren't going anywhere!

[GRN69CHV]

I did a 1" front end lift (approx. 1/2" thick lower spacer). 1" doesn't seem like a lot, but it was just enough to get rid of a lot of that nose down attitude while still keeping plenty of rake to level out the truck when towing or hauling a load. Within reason, there is enough suspension travel built into the front ends to allow the front ends to operate within intended design geometry. Think about what happens when towing, by design, you add load to the rear of the vehicle and intentionally unload the front end. As for travel, suspension travel is limited by the bump stops. If you go and raise (or lower) the vehicle and modify/remove the bump stops, you can be guaranteed to set yourself up for suspension component failure. I tend to stay conservative though, 1" to 1.5" front end height adjustment is more than enough for my needs.

 

PS, had my truck aligned at stock ride height, never had it rechecked after the 1" lift, tires are wearing perfect. Noticed no difference in handling, etc.

[GMC-AT]

what ever you decide, don't go over 1.5in. These trucks need to maintain 1.5-2 rake in the front to look right. A "true" front to rear level looks like garbage IMO.

Plus, the ride characteristics really start to change when you go higher that 1.5.

 

I have tried every level made between my old 2014 and new 2016 ( top, bottom strut, Bilstein 5100, Rancho Quick lift) I can tell you - 1.5 in under strut with stock socks is the best IMO. ( look and ride)