Towing shocks bilstein 5100 vs 4600

[calgator73]

Spoke to NC sales today regarding availability and was told that the rear 5100s are out and the front shock part numbers should be available just before SEMA in November. I asked the differences between the 13 and 14 since people are putting the older part# on the 14s. He stated that the new design has an integrated bump stop that the older version did not have. He wasn't sure about compression and rebound rates.

 

I told him that I had installed supersprings on the rear axle to decrease the amount of porpoising (yes wdh is at full load restoration) caused by the various bumps on the interstate and that it mostly worked but my unloaded rear height was too high for my taste and that my intent was to add the 5100s to both increase my front height (restore original rake) and provide additional damping. He recommended that I use the 4600s instead of the 5100s and consider removing the springs. His claim is that when compared to the 4600s, the 5100s are designed to be easier to compress with about the same rebound damping.

 

Thoughts?

[Spurshot]

I really liked my 5100s front and rear in my 08 crew 4wd. I think that's the way I'm going again for my 2014.

[Spurshot]

I had 4600s in my 99 1/2 2500 and was very pleased as well.

 

 

My OEM Rancho shocks in this 2014 are too stiff for my taste and they stack on rapid movement.

[sugarjohnson]

Anyone know what rear shocks are used on a 2014 6.2L with the max tow? They are different and list them as "revised shock tuning" as part of the max tow package.

[calgator73]

Should be the same for all nht. Not sure if factory shocks are bilstein or not. Sales rep claims that if they are then he can look the specifications up and compare against 4600/5100. Just gotta get some numbers off the shock.

[Spurshot]

Probably Monroe gas shocks. My 08 NHT had 46mm gas shocks, but they didn't have good damping and they were the first thing to go on that truck.

[sugarjohnson]

Guess I'll crawl under and check once it stops raining here

[TJay74]

I can tell you now, the Rancho's on the AT package suck on washboard roads. I ran over a bunch of rough spots on the road the other day and the rear end of the truck started bouncing all over the road.

[Spurshot]

I can tell you now, the Rancho's on the AT package suck on washboard roads. I ran over a bunch of rough spots on the road the other day and the rear end of the truck started bouncing all over the road.

I agree. Too much damping on compression and extension.

[calgator73]

If they are bouncing wouldn't that be not enough damping?

[thetruck454]

If they are bouncing wouldn't that be not enough damping?

That depends on when the bounce is relative to the bump. Too much compression is when it hits hard at the bump because it won't compress to absorb. A bounce right after the bump is due to the rebound not high enough to return the shock to its normal position

[Zak.V]

Dampening in a shock works by metering oil flow through the valve stack (think of a piston with small holes in it) if compression dampening is too strong on fast movements the shock can't move the oil fast enough and causes large resistance. This can lead to the suspension losing its plushness and even cause bouncing. The same can be true with rebound dampening. Rebound is the characteristics of the flow as the shock extends. Too much dampening and it won't let the suspension extend back to normal position. In washboard it keeps the suspension packed and leads to poor performance. Of course too little dampening leads to bottoming out and topping out. This feels more like very hard sharp hits at full travel or max extension

[Jon A]

The damping rate is a curve (two actually) vs. input velocity. It's possible (and quite common) for a shock to have too much damping in one part of the curve and not enough in another.

 

I felt the Ranchos had too much high speed compression damping (very harsh feel on bumps) while having not nearly enough low speed rebound damping (controlling body motions, eliminating floaty, bouncy feel).

 

The Bilstein 5100's (for 2013's and under) are dramatically better, giving a much better ride over bumps and controlling body motions better. However, I still feel they need more low speed rebound. I think they upped the front spring rate for 2014 so the 2013 5100's are less than optimum. Hopefully they addressed this with the 2014 5100's, but I don't think anybody has confirmed it yet.

[calgator73]

I'm considering the rancho 9000 so i can customize the ride. Wish there was a factory autoride available. Loved the way my Denali would adjust.

[Spurshot]

The damping rate is a curve (two actually) vs. input velocity. It's possible (and quite common) for a shock to have too much damping in one part of the curve and not enough in another.

 

I felt the Ranchos had too much high speed compression damping (very harsh feel on bumps) while having not nearly enough low speed rebound damping (controlling body motions, eliminating floaty, bouncy feel).

 

The Bilstein 5100's (for 2013's and under) are dramatically better, giving a much better ride over bumps and controlling body motions better. However, I still feel they need more low speed rebound. I think they upped the front spring rate for 2014 so the 2013 5100's are less than optimum. Hopefully they addressed this with the 2014 5100's, but I don't think anybody has confirmed it yet.

 

Your assessment of the factory Ranchos reflects mine too.

 

The 5100s I had in my 08 worked well for the high rate suspension movements, but the low speed movement of the suspension was under damped by a lot. If they increased the spring rates in the 14 trucks, this characteristic will be amplified if the old shock is used in the new truck.