Sponsored

Skyjacker 2/2.5 install questions

homebrew

Well-Known Member
First Name
paul
Joined
Jun 21, 2018
Threads
105
Messages
234
Reaction score
145
Location
Washington
Vehicle(s)
18 Wrangler JL Rubicon
Isn’t the point of progressive coils supposed to be the tight coils provide your street driving and the spaced ones provide your off-road travel( for lack of better words) just put the coils on the front of my Rubicon, the tight coils are completely compressed under the jeeps body weight+ winch.

Jeep Wrangler JL Skyjacker 2/2.5 install questions 88C04BA7-3EA0-4619-91CC-48C3BB92C72A
Sponsored

 

Carlton

Well-Known Member
Joined
Sep 2, 2018
Threads
23
Messages
2,912
Reaction score
3,247
Location
Chicago
Vehicle(s)
Jeeps lots of jeeps
In my experience, every brand of progressive rate springs has looked similar to this once installed. Despite the popularity of progressive rate coils, I prefer linear coils. I find them to ride smoother.
 

Arterius2

Well-Known Member
First Name
Jerry
Joined
Dec 29, 2018
Threads
42
Messages
3,527
Reaction score
4,857
Location
Vancouver, BC
Vehicle(s)
2018 JLU Sahara 2.0L
Isn’t the point of progressive coils supposed to be the tight coils provide your street driving and the spaced ones provide your off-road travel( for lack of better words) just put the coils on the front of my Rubicon, the tight coils are completely compressed under the jeeps body weight+ winch.

88C04BA7-3EA0-4619-91CC-48C3BB92C72A.webp
@Carlton
So what is the point of the dual rate coils if the tighter portion are essentially just a solid block of steel for on-road driving?
 

Carlton

Well-Known Member
Joined
Sep 2, 2018
Threads
23
Messages
2,912
Reaction score
3,247
Location
Chicago
Vehicle(s)
Jeeps lots of jeeps
@Carlton
So what is the point of the dual rate coils if the tighter portion are essentially just a solid block of steel for on-road driving?
The compressed section is the dead zone. It is only used during long travel/drop out. The section below that is the ride zone.
 

Arterius2

Well-Known Member
First Name
Jerry
Joined
Dec 29, 2018
Threads
42
Messages
3,527
Reaction score
4,857
Location
Vancouver, BC
Vehicle(s)
2018 JLU Sahara 2.0L
The compressed section is the dead zone. It is only used during long travel/drop out. The section below that is the ride zone.
Well that’s a little different than other explanations I’ve heard. What you’ve mentioned is true for suspension droop, I don’t question that.

I was told that the tighter portion of the spring provides a lower spring rate than the rest, so they compress first, and would give a plusher ride for smaller bumps, once the tighter sections are compressed, the 2nd portion gets compressed at a higher spring rate, hence why it’s called dual rate.

Now my issue is that the Jeep at rest already completely compressed the lower spring rate portion, that doesn’t sit right with me. Reason being that if 25% of your coil is basically “incompressible” then most of the compressive force act upon the other 75%, so less of the spring actually absorbs the energy and that would either give you a stiffer ride or introduce more stress to the metal. But then again, I’m only going off with what I’ve heard.
 
Last edited:

Sponsored

Jerrybizzle

Well-Known Member
First Name
Jerry
Joined
Aug 28, 2018
Threads
12
Messages
330
Reaction score
291
Location
Idaho
Vehicle(s)
2019 JLUR
Occupation
Tech
Seems there should be some gap between the first rate coils. Do you also have an aftermarket bumper that’s pretty heavy or just the winch? That seems more compressed than they were designed for.
 

word302

Well-Known Member
Joined
Sep 13, 2017
Threads
11
Messages
5,210
Reaction score
5,870
Location
Oregon
Vehicle(s)
JLU
Seems there should be some gap between the first rate coils. Do you also have an aftermarket bumper that’s pretty heavy or just the winch? That seems more compressed than they were designed for.
Nah that's likely as designed. Most dual rate coils are designed to be fully compressed on road. They are there specifically for the droop when off road.
 

Arterius2

Well-Known Member
First Name
Jerry
Joined
Dec 29, 2018
Threads
42
Messages
3,527
Reaction score
4,857
Location
Vancouver, BC
Vehicle(s)
2018 JLU Sahara 2.0L
Nah that's likely as designed. Most dual rate coils are designed to be fully compressed on road. They are there specifically for the droop when off road.
The spring compression animation showed in RK’s video don’t show the upper portion completely stacking together when compressed.
 

Sponsored

Carlton

Well-Known Member
Joined
Sep 2, 2018
Threads
23
Messages
2,912
Reaction score
3,247
Location
Chicago
Vehicle(s)
Jeeps lots of jeeps
The spring compression animation showed in RK’s video don’t show the upper portion completely stacking together when compressed.
I've had three Rock Krawler lifts. 3.5 inch and 5.5 inch kits. Top coils were fully compressed. This is how they are meant to function.
 

word302

Well-Known Member
Joined
Sep 13, 2017
Threads
11
Messages
5,210
Reaction score
5,870
Location
Oregon
Vehicle(s)
JLU
The spring compression animation showed in RK’s video don’t show the upper portion completely stacking together when compressed.
Lol, watch it again. When he talks about the upper "dead zone", he refers to it being completely compressed on normal on-road driving.
Sponsored

 
 







Top