SDi Top Hats + Icon Overland HD rear coils w/37s on 35 truck

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Rob O

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Cross posting this with the "what did you do to your Gen 3 today" thread, but adding a couple more tidbits ...

Installed the following last week:
SDi Top Hats (claimed 1.75" of lift)
Icon's new Overland HD rear springs (claimed 1" of lift)
FP Forged FP3-SL wheels (17x9 +12)
37x12.5 KO2s (Load Range D version at 38psi)
(still have Foutz UCAs on the way, and will do Index's rear bump stop and eyelet solutions at the same time)

TL;DR: Above mods resulted in 2" to 2.5" of total lift (ground-to-fender), about 1" more fender gap (compared with factory 35" set up) and the new tire/wheel set up is about 1lb heavier per corner (compare to factory 35" tire/wheel)

Only have a handful of miles on it with the new new, but can say it rode great. Couple of initial observations:
1) The 37s feel "substantial", even though the new tire/wheel combo is almost exactly the same measured weight as my 35s on OE 17s
2) The ride feels "tighter", and maybe a hint firmer, but not stiffer (which is fine in the bedroom, but not on the road). When I say tighter, I mean it felt less sloppy and more buttoned up. The factory suspension on road is fantastic IMO; it's the main reason to buy a Raptor over anything else if towing/hauling aren't a necessity. But it's a bit soft in certain circumstances and a little loose in corners. This simple change -- top hats and taller HD coils -- had a measure effect in making the truck feel just a bit more solid
3) The shop added in some camber during alignment, but the front passenger tire still hits the Rock Blockz mud guard in reverse with the wheel turned. Probably remove those, and only ran them because I had spacers with the factory wheels to mimic 0 offset (to see if I could live with it).
4) Even being just a couple inches, you can feel the extra height from the driver seat ... and when getting out. LOL
5) Shop couldn't get the spare with 37 to fit. I forgot to give them tips on what was needed for a 37 spare to fit on 35 truck, so I'll "convince it" to get up under this week.
6) Plan to update tire size with Forscan tomorrow

Will circle back with better (proper) photos when I get a chance. For now, a couple iPhone snaps are attached.


For those who like data


Ride Heights before* and after**

Before*** - Front
Driver: 40" ground-to-fender and 6 7/8" fender gap (top of tire to bottom of fender flare)
Passenger: 39 3/8" and 6 5/8"

After - Front
Driver: 42 1/2" and 7 3/4"
Passenger: 42 1/4" and 7 1/4"

Before*** - Rear
Driver: 40 1/4" and 7"
Passenger: 40" and 6 7/8"

After - Rear
Driver: 42 3/4" and 8"
Passenger: 42 5/8" and 8"

Doing the math, these are the net lift figures ...
Driver Front: +2 1/2" and 7/8"
Passenger Front: +2 5/8" and 7/8"
Driver Rear: +2 1/2" and 1"
Passenger Rear: +2 5/8" and 1 1/8"

*Measured in the exact same spot in my garage, on level ground
**Not sure how settled the rear coils are, but it has bee several days. Payload before/after is identical
***Stock 35" KO2s had roughly 28k miles on them and measured around 10-11/32 of tread (new is 15/32)


Wheel/Tire Weights

OE 35 KO2 setup with factory bead lock 17s after 28k miles (see note above): 100 lbs*
FP3-SL + 37" Load Range D KO2s: ~101 lbs**

More detail in wheel thread

*Mounted weight; don't have separate weights for wheel and tire
**Measured wheel and tire individually before mounting but did NOT measure them again after mounting
 

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MDJAK

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Excellent upgrade and writeup. Are those real beadlocks? I went from a 35 to a 37 and notice the step in and out difference in height. I couldn't imagine going higher.
 
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Rob O

Rob O

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Excellent upgrade and writeup. Are those real beadlocks? I went from a 35 to a 37 and notice the step in and out difference in height. I couldn't imagine going higher.
Simulated ... but removable, forged rings not "beauty rings" or part of a whole wheel casting.
 

AZ4RDRPTR

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I am between Geiser Progressives and Icon Triple Rate Overlanding springs. I am looking to eliminate sag when towing a little overloading camper, and just a "tighter" feel to the truck when daily driving like you stated. What made you decide to go with the Icons and do you think they were the right call for your added weight with the shell on the back? @Rob O
 
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Rob O

Rob O

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I am between Geiser Progressives and Icon Triple Rate Overlanding springs. I am looking to eliminate sag when towing a little overloading camper, and just a "tighter" feel to the truck when daily driving like you stated. What made you decide to go with the Icons and do you think they were the right call for your added weight with the shell on the back? @Rob O
Can't say there was anything specific that made me go Icon over the others. The Icon Overland springs (and "regular" triple rate coils) are new to the market. I'd been deliberating between the usual Eibach HD vs Geiser, both of which are "tried and true" with reviews and feedback ranging from perfect to just okay, depending on the owner and situation. I regularly have at least a hundred pounds of stuff in the bed, plus the SmartCap which is about 200 lbs, and often doing 3000 mile road trips with 300-500 lbs of gear (my daughter is a competitive equestrian). So it really just came down to comparing specs side-by-side, and kinda taking a chance on the Icons based on them seeming like the best match for my use case purely from manufacturer product descriptions (and promises) vs reviews. I have a few road trips coming up and that'll be the real test, to see how the coils handle my typical payload at Interstate speeds for miles on end ... then off pavement, without everything but still the topper and some gear.
 
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Rob O

Rob O

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Couple better photos.

Note that I removed the RokBlokz mud guards. I initially decided to get them because I was running spacers with the OE 17" 35 set up to see if I could live with zero offset. It was so aggressive, I felt added protection was needed ... at least in winter (even with full PPF). With the FP3-SL at +12 offset, and the way the tires are sort of "pinched" by the SBLs, the corresponding poke is perfect ... and doesn't warrant running mud guards (which are a polarizing look, regardless of functionality).
 

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