Anyone know what the factory front and rear spring rates for 2018 GX460 premium are?

I’m looking for 2” lift for the rear Of my vehicle for the new shocks, but my understanding is that aftermarket 2” lift “Factory rate” springs, such as dobinsons, are designed for 4runners which will give significant sag on a GX. Same reason why I went with a 600lb spring rate instead of standard 550lb for the front coilovers, which is made for a 4runner weight.

The Superflex or superflex HD or the dobinsons 220-400lb comes to my mind but I just feel that they may be too stiff for a daily driver with only a tire carrier in the rear. What do you guys think? A slight stiffness is welcome.

 

Alright! Lol

 

I can't say I have ever seen that listed in any of the FSMs I have.

 

If you check on rock auto you can generally find the factory oem spring rate by looking at the aftermarket replacement spring specs. It’s not exact but it’s real close.

The front spring rate is higher on the GX because it has a v8 verse v6 in the 4Runner. Rear is higher cause 3rd row verse no 3rd row for the base 4runner.

 

do you guys think OME 889, 200 to 400lbs or Dobinson 200-400 are too stiff for stock GX with a roof rack and a tire carrier with a 33"?

These springs are made for a Prado 150, not a 4runner. I'm not sure what the weight difference between a 150 and a GX.

 

I can help you out a little with the Dobinsons portion of the question.

I'm running the 1.5-3.5" lift kit from Dobinsons. Bought it all from Mike at ExitOffRoad, great dude to deal with, call him if you have some questions/concerns.

Front coils: C59-314 - I don't see a spring rate, but if I recall they're about 100 lb more than the Prado versions, to account for the additional V8 weight
Front struts: GS59-700
Rear coils: C59-327 - "271LB Rate" or from what I recall they're 200 lb more than stock (though 271 would make sense)
Rear shocks: GS59-701

On my rig, it gave a nice 2.5 (+/- 0.5) inch lift in the front and a 3 (+/- 0.5) inch lift in the rear, didn't actual measure the results, just eyeballing it.

Ride definitely stiffened up some, but not bad. When I ride unloaded in the back (no spare, no gear) it's more notable. With my trailer on, some gear, spare, etc, it's pretty darn nice.

Obviously I can't speak about ride here and have it translate perfectly to you, but IMO if you don't mind it stiffening up some when unpacked, you just don't want a rough-as-hell ride, then I think it's a great setup, particularly when you're packed some with a 70lb spare tire and some gear. If you want it dialed in pretty precisely, then you might want to go with a bit lighter springs, definitely not the 200+ lb rears.

I don't have any direct side-on shots of the lift, but maybe this will help.



Loaded up:

 

Thanks, Jman,

That's why I think I will probably go with the Superflex HD which are rated at 150 to 200lbs, and it says it will give 2-2.5" of lift.

So with your dobinsons 327's, I think they are 200 to 400 lbs rated, how do they ride unloaded? Would you consider it too stiff?

 

Unloaded, which for me means no 3rd row (150lbs?) and no spare (70+lbs), is on the limits of my personal desire for stiffness. It’s not what I’d say is too stiff or uncomfortable, it’s similar to what a Tundra feels like with those truck leaf springs in the back, stiff but not obnoxious.

If you’re concerned with it being too stiff and don’t need the weight carrying capacity, my opinion would be to go with those slighter lighter springs you mentioned, they should be a little more forgiving yet do what you need from them.

 

Here are some data for ya for rear springs. It was near impossible to find these numbers and every shops quotes different specs. It really shows who "really" knows their stuff
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Remember these numbers are based on 4runner weight, so add 100 to 200lbs on your constant load weight for a GX and it will sag 1/4" to 1/2".

Stock GX rear springs - roughly around 180lbs per in.
Stock 4runner rear springs - 150lbs.

Icon 52700 - 210lbs, lifts around 2" at stock weight.
Dobinson C59-325 - 220lbs, lifts around 2" at stock weight.
Toytec Superflex HD - roughly around 240lbs, lifts about 2" with 150-200lbs constant load.
OME 2889 - 260lbs, lifts 2" to 2-1/2" with 200 to 400lbs constant load.
Dobinson C59-327 - 271lbs, lifts 2" to 2-1/2 with 220-440lbs constant load.

With the weights I will be carrying (roof rack with accessories, tire carrier with 33" tires, and other everyday things in the trunk and back seat of the vehicle), I think Dobinson C59-327 or OME 2889 would work perfectly and would give about solid 2" to 2-1/2" of lift.