THEGAW

First of all, what's up guys, by my post count you can see I'm new here. I've done a ton of looking around here and over on ecoboost forum.

I really hate to beat this dead horse but I'm looking for specific bilstein info that I haven't seen examined from this angle.

As far as I've found there are basically 2 coil spring codes for the front of the 09-14 trucks. UU and VV. I've got V code coils on my '13 FX4 crew eco "145.

I've got bilsteins I'm going to install soon and I'm torn on top setting or 1 down. From my perspective somewhere between the 1.5" and 2.25 would be perfect. I've seen varying net height gains at the same setting and I'm curious if this is due the the coil spring code installed on the strut.

First of all can anyone confirm that the VV code coils are heavier rate than the UU coils? I'm thinking they are. If this is true, then by logic I might assume that preloading a VV coil the same distance as a UU coil would gain me slightly more lift say at the 1.5" setting because the coil won't compress as much under the vehicle weight. Does this make sense logically to you guys also.

What height gains did you guys measure at the second from top setting and with what coil code?

GrasslandHVAC

I have a 3.7 scab and the UU spring code. I would assume the VV is heavier rate.

flamehead16

most run on 2nd to top setting as the top setting may cause binding.

antony1103

I've been trying to hunt down an answer for a while now. I'd love to know the stock spring rates.

TexJ3

I read somewhere they were around 400-450 lbs/in, but I never verified.

THEGAW

For which code? U or V?

antony1103

I've heard something similar, but again, nothing verified...

I'd like to start experimenting with different spring rates/lengths, but I need to know what I have to begin with first...

RedAggie03

One spring is for the 3750 GVW vehicles and the other are for the 3900 GVW rated vehicles.

User HSBII has swapped springs with 5100's for this reason...You might reach out to him, he came up with a very clever solution of spring rates, 5100's, and Raptor top hats/spacers.

Kytann

When I looked up the information years ago the best I could come up with was between 500-550 lbs/in.
I think the 400-450 lbs/in rating is for the newer 2015+ truck and their lower weight.

It would be cool to see that data for the actual spring rates. My new Fox 2.0 Coilovers at 650 lbs/in feel noticeably stiffer than stock, but interestingly not harsher.
I need to flex the suspension out to check the balance front to rear.

THEGAW

Thanks for the insight.

Just knowing that the v code spring is a little heavier I have to assume it may yield a little more than the advertised 1.5" at the second from top. The 5100 install instructions even say that various factors affect the overall lift provided at the different settings. I imagine spring rate has to be one of those factors.

Was hoping people who have done bilsteins with different spring codes would chime in with the real world results they got. Anyone?