Front Spring Rates Table for Gen 14?

[MtnBiker2341]

Looking for a spring rate table for the various F-150 configurations. I see one for the '15+ on another forum but nothing for Gen 14 updated for config and Ford Part# (or Engineering Number). I have a '23 Lariat Supercrew 4x4 with 302a, FX4 and Max Tow. Front springs seem to have a higher rate than standard. Shopping for coil-overs like the Eibach 2.0's gets a little complicated since I can't compare a 450 lbs/in Eibach spring rate to what I have in my truck. Don't want to lose too much tow capacity if any. Ford parts catalogs are no help as you might expect.

Sponsored

 

[SALEEN961]

 

[MtnBiker2341]

So 3600 lbs combined rating, looks like 514 lbs/in vs 450 on the Eibachs. Probably need to go with the Pro-Truck Sports with OEM spring then.

Thanks for the Info!

 

[JCsTruck]

I’m curious how one correlates the spring rates on that chart to the different models and configurations they have?

 

[MtnBiker2341]

I want to say the front axle rating correlates to basic configuration. In my case the 3,600 lb Gross Axle Weight Rating is for a 145" wheelbase Supercrew with Max Tow. The Lariat with 302a package eats up some of the payload vs a stripped XL. It's all about the door stickers.

 

[SALEEN961]

So 3600 lbs combined rating, looks like 514 lbs/in vs 450 on the Eibachs. Probably need to go with the Pro-Truck Sports with OEM spring then.

Thanks for the Info!

My 2021 came with 514lb/in front springs and I've used Fox 2.0 kits with 450lb/in springs and 550lb/in springs without any issues. I prefer the 450lb/in kit because it reduces understeer and makes my truck feel more balanced in high speed turns. When I had my 2014 F150, the Fox kit I ran on it came with 650lb/in springs that I later swapped out for 450lb/in springs. The front end felt much lighter and the steering response was quicker with the 450lb/in springs.

The being said, if you tow heavy or often carry heavy loads, a higher spring rate could be beneficial.

 

[Hotshot Offroad]

So 3600 lbs combined rating, looks like 514 lbs/in vs 450 on the Eibachs. Probably need to go with the Pro-Truck Sports with OEM spring then.

Thanks for the Info!

Are you wanting the higher spring rate on your OEMs because you are planning for added weight in the front? We ask because if you are not adding weight in the front, we would argue the Eibach Stage 2 and 2R kits are superior in ride quality over the pro truck kit with OEM coils. And you can still get up to 3" of lift on the front with the lower spring rates (pending you dont have a Tremor or PB trim).

 

[MtnBiker2341]

Are you wanting the higher spring rate on your OEMs because you are planning for added weight in the front? We ask because if you are not adding weight in the front, we would argue the Eibach Stage 2 and 2R kits are superior in ride quality over the pro truck kit with OEM coils. And you can still get up to 3" of lift on the front with the lower spring rates (pending you dont have a Tremor or PB trim).

Great question and hopefully informative to the forum (Ford counts about 120,000 Max Tow packages from '21 - '23). The next step down, non Max Tow, in OEM spring rates on F-150s is from 434 - 474 in/lbs which is close enough for Eibach's 450 spring. Lowering the Max Tow front spring rate from 514 to 450 would lower front GAWR and payload by some amount. The Max Tow also has a higher spring rate in the rear possibly impacting chassis balance?? Just seems to me that preserving capability if you shelled out the cash for Max Tow makes sense.

Eibach does sell 500 lb/in springs in the 3.0 x 14 inch size for not a lot of $$ so assuming it would be easy enough to firm up the springs if wanted.

(And not a Tremor/PB. Just a 3.5 EB)

 

[astro_fusion]

My 2021 came with 514lb/in front springs and I've used Fox 2.0 kits with 450lb/in springs and 550lb/in springs without any issues. I prefer the 450lb/in kit because it reduces understeer and makes my truck feel more balanced in high speed turns. When I had my 2014 F150, the Fox kit I ran on it came with 650lb/in springs that I later swapped out for 450lb/in springs. The front end felt much lighter and the steering response was quicker with the 450lb/in springs.

The being said, if you tow heavy or often carry heavy loads, a higher spring rate could be beneficial.

Do you recall how much ride height change happened when you went from the 650 to 450 springs?

 

[SALEEN961]

Do you recall how much ride height change happened when you went from the 650 to 450 springs?

I set the ride height to be the same as it was with the 650lb/in springs. The spring rate doesn't really impact ride height on an adjustable coilover, but softer springs will need more preload measured in inches to get the same preload measured in pounds when compared to stiffer springs.

I'll also mention that my memory was a bit off, I actually installed 400lb/in springs on my 2014. I think I initially wanted 450lb/in springs, but I wound up getting 400s because the 450s were backordered.

Sponsored