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Bilstein 5100 vs spacer level

Boost Monkey

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No, last I checked the Ram 1500 springs are progressive.

So you are 100% confident that both the front and rear coils are progressive? If so, are they dual rate progressive or full progressive?

Dual rate progressive springs are far more akin to linear springs. Almost all of the bump/droop travel will be within one of the two rates and, trying to word this as least confusing as possible, all compression/rebound within the full range/length of each rates' section of the spring with be linear. Typically the second rate part of the spring acts like an integrated helper spring. This all means that if they are dual rate, compressing the spring to change height with have a pretty minimal impact (if even felt at all) on the ride stiffness.

As for fully progressive, yeah that's different but although I could easily see the rear coils being fully progressive (serving a strong role in load management), I have a harder time believing that the front coils are fully progressive. Linear rates give you predictability in the suspensions' rebound/compression performance when handling bumps... Typically what you want on the steering end of the chassis.
 

RebelWraith

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So you are 100% confident that both the front and rear coils are progressive? If so, are they dual rate progressive or full progressive?

Dual rate progressive springs are far more akin to linear springs. Almost all of the bump/droop travel will be within one of the two rates and, trying to word this as least confusing as possible, all compression/rebound within the full range/length of each rates' section of the spring with be linear. Typically the second rate part of the spring acts like an integrated helper spring. This all means that if they are dual rate, compressing the spring to change height with have a pretty minimal impact (if even felt at all) on the ride stiffness.

As for fully progressive, yeah that's different but although I could easily see the rear coils being fully progressive (serving a strong role in load management), I have a harder time believing that the front coils are fully progressive. Linear rates give you predictability in the suspensions' rebound/compression performance when handling bumps... Typically what you want on the steering end of the chassis.
Fronts are full progressive. Dual progressive would be visually noticeable.

Front progressive springs are generally used for higher comfort levels.
 

Bignick75

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It's not a question of brand it is just a side effect of the type of system. I had the 5100s on my truck and removed them and tried the 6100s. Removed those as well. Now using FOX racing 2.5 DSC coilovers.
Mind posting some pics? Your info says 3” fox lift im curious how it looks compared to the 3” fabtech lift. Thanks!
 

Patamaran

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so what's the consensus on UCA replacement? If i get bilstein 5100s that would still affect the angle, at what point do you have to change the control arms?
 

Jammer 183

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so what's the consensus on UCA replacement? If i get bilstein 5100s that would still affect the angle, at what point do you have to change the control arms?
I’ve been told if you go over 2” you should do the control arms.
 

70runner

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so what's the consensus on UCA replacement? If i get bilstein 5100s that would still affect the angle, at what point do you have to change the control arms?

From what I've gathered, pretty much your call. I believe the OE Rebel UCA is the same reinforced, composite plastic UCA used on all 1500s. As such, it's already dealing with an approx 1" lift with ORP/Rebel configurations. Swapping in 5100s to level the Rebel adds approx 2", so there would be 3" of lift imposed on the OE UCA as compared to a non-ORP/Rebel 1500. Many offroad, suspension outfits seem to use 2-3" of lift as a general threshold for UCA upgrade. The last thing I'd want to worry about in a "leveled" Rebel is a UCA/front suspension failure, particularly if used offroad. My old, retired structural engineer brain would lean toward an upgraded UCA for improved ball joint angle and construction. Sure there are folks that do the 5100 mod on a Rebel without a UCA upgrade, like I said, it's your call.
 

H2OMAN

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If you want to do the UCA's that's great. Just remember, on the Bilsteins it is a pre-load. You are not lengthening the strut like you are with pucks. Your coil over is the same lenght as your stock strut irregardless of what you set the lift at. The only thing you are losing is travel. So, UCA's not needed. You are not changing geometry..
 

JerryBsizzle

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H20MAN is correct! Which is a big reason why I hate spacer leveling kits.
 

z0n3

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Going to be throwing these on when I do my 5100's later this month. Ill be on ORP with 2" form the bilstein so at 3" total level its safer to do the UCA upgrade than to hope to stock UCA's last.
1620663965678.png
 

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