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Comparing stock Tremor suspension to Bilstein 4600 or 5100

Porpoise Hork

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Don't have a tremor but the 5100's are a massive improvement over the FX4 shocks/struts. Especially for rebound damping the FX series are known for being too soft which causes that rolling boat like ride. :sick: The 5100's basically eliminate it.

The 4600's would be an OE replacment like you would get on a stock 2wd version suspension. Still be perfectly fine for a pavement princess daily driver. Any significant unpaved roads or off-roading then step up to the 5100's. Not much different on the street than stock but still a bit better than the 4600's.
 
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MTMan

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I don’t know about the F150 application but when I talked to Bilstein about my Land Cruiser regarding the differences between the 4600 & 5100 they basically said the 5100s are US made with a different finish but the exact same internals and damping inside except the 5100s were made for lift.
 

Porpoise Hork

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Interesting they are essentially the same internals. When I spoke with them a few years ago the rep told me about the use cases for light to moderate off-roading. That the 5100's were considered "heady duty." He did say that the front struts have groves to mount the spring perches at different heights to raise the suspension if desired.
 
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MTMan

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The 4600 is more of a worldwide shock for its applications whereas the 5100s for what we do in North America.

I’m guessing the Tremor shock is probably in between the FX4 and Bilstein. I don’t like how the rear axle on my FX4 jumps around on corrugated roads. However, I’m going a different route of the majority as I’m wanting to keep my fuel range up which requires not lifting and keeping the tire size stock at 33 better than the stock 32s. Just wanting to get it more planted on rough roads..
 

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MTMan

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Interestingly doing a little google search some are saying same internally and some different valving. If I get a chance, I'll try to get some more info direct.
 

Porpoise Hork

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The 4600 is more of a worldwide shock for its applications whereas the 5100s for what we do in North America.

I’m guessing the Tremor shock is probably in between the FX4 and Bilstein. I don’t like how the rear axle on my FX4 jumps around on corrugated roads. However, I’m going a different route of the majority as I’m wanting to keep my fuel range up which requires not lifting and keeping the tire size stock at 33 better than the stock 32s. Just wanting to get it more planted on rough roads..
I ran the 4600's on the rear in my 20 Ranger and it was a lit better than stock. Even on dirt roads. I went with the 5100's on the F150. Granted apple to oranges here but the off road handling is better in the F150 with them than the 4600's were in the Ranger. Both had the same stock FX shocks and mushy ride. Honestly either is a good upgrade and will help the back end feel more planted/stable than the OE dampers.

Looks like there are some minor internal differences too.

https://www.shocksurplus.com/blogs/...vs-5100-series-what-are-the-major-differences
 
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MTMan

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Yeah, probably going to pick one. Waiting on some specs from Bilstein. Hard to compare with a Ranger due to the differences in weights of the vehicle which is what makes the F150 ride so much better to begin with.
 

CoryT

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Stock Tremor felt like a floaty boat to me. I tried the 5100 Bilsteins with the OEM springs but it didn't offer enough of an improvement. Ended up replacing everything with the Eibach 2R, really happy with the result. Rides much better on street and on the washed out back roads I need to use.
 
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MTMan

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I wonder what the OEM FX4 spring rate is? Bilstein replied:

Hi,
I’m sorry to report that I cannot disclose the exact valving characteristics between these products, as our direct-fit valving profiles are proprietary and privately owned information.
Generally speaking, I can share that the 5100 shocks for this application are valved stiffer because they are intended for lifted vehicles.
The heavier valving helps control the additional top-heaviness that comes with a higher center of gravity, improving handling and stability.
Thanks!
 

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Porpoise Hork

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I wonder what the OEM FX4 spring rate is? Bilstein replied:

Hi,
I’m sorry to report that I cannot disclose the exact valving characteristics between these products, as our direct-fit valving profiles are proprietary and privately owned information.
Generally speaking, I can share that the 5100 shocks for this application are valved stiffer because they are intended for lifted vehicles.
The heavier valving helps control the additional top-heaviness that comes with a higher center of gravity, improving handling and stability.
Thanks!
That's a near identical response I got from them a couple years ago when I got the F150 and was looking at the 5100's for it.
 
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MTMan

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I thought they used to do this. What I like about the 5100s is the better finish on it and the flexibility of doing stock or a lift in the future if I end up going that.

Really, I’m just trying to get the best mix for the adventures I do. Hadn’t thought much about this until noticing how bad the rear axle does on corrugated roads.
 

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I wonder what the OEM FX4 spring rate is? Bilstein replied:

Hi,
I’m sorry to report that I cannot disclose the exact valving characteristics between these products, as our direct-fit valving profiles are proprietary and privately owned information.
Generally speaking, I can share that the 5100 shocks for this application are valved stiffer because they are intended for lifted vehicles.
The heavier valving helps control the additional top-heaviness that comes with a higher center of gravity, improving handling and stability.
Thanks!
What a weird response. You can just open a shock up and see the valving. I'm sure all their competitors know exactly what they use.
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