Spacer thickness vs. actual lift

[Sixpack577]

PLEASE READ THIS COMPLETELY BEFORE TELLING ME TO SEARCH, AS I HAVE REPEATEDLY WITH NO RESULTS.

Can someone please tell me the actual amount of lift a front spacer provides on a 3rd gen? I also understand that they will vary slightly on all 4runners.
They are all advertised as not being a 1 to 1 lift ratio.
That the lower control arm compounds the amount of lift due to lower arm's angle and length.
So for example; Does a 2" spacer provide 2.5" of lift? 3"? 3.5"?
I cannot spend a grand on a full suspension lift now.
I have an 01, and a new set of 99 springs that should make the 4runner sit level once I have time to install them. I would like to add spacers at the same time.
My 01 sags alot in the rear, but for whatever reason I still can't post pics.
Moderators, any ideas on the pics?

Anyway, I assume and hope the 99 springs will get my 01 level, or slightly raised in the rear.
I would also like to use some spacers to get it just slightly higher to make getting in and out easier, as well a little ground clearance.
A 3" front spacer is too much for me now.
I was planning on adding a 1" front spacer, and 1.5" rear spacer with the 99 springs.
Assuming I had my 01 level or slightly raised in the rear before spacers. Is an advertised lift of .5" higher in the rear enough to make it sit level.
Should a 1" front spacer provide 1.5" of lift? 2"?

All my searches on this forum as well as a few others only turn up countless repetitive info that does not answer this question.
They all show pics of spacer lifts, and all of them sit lower in the rear.
Can anyone answer these questions?
Thanks.

 

[PitbullRescuer]

All I can tell you is that when I used 1/4" top hat spacers on my 99 that they actually gave about 1/2" of lift. Doesn't mean the ratio is 2:1 though, those were just my results.

 

[Sixpack577]

All I can tell you is that when I used 1/4" top hat spacers on my 99 that they actually gave about 1/2" of lift. Doesn't mean the ratio is 2:1 though, those were just my results.

Thank you sir. That's the type of info I'm looking for.

 

[Alabamaguy]

Everything I have seen shows a 2:1 ratio. I believe its because of the suspension geometry but im not exactly sure.

 

[steezemcqueen]

Correct. It is roughly a 2:1 ratio.

 

[Sixpack577]

Correct. It is roughly a 2:1 ratio.

Thank you both.
I assumed it was roughly a 1.5 to 1 or a 2 to 1 ratio, but I wanted to hear it from people more familiar with 4runners than I am.
I'm going to put my 99 rear springs in hopefully wednesday, then I'll order spacers.
I think I'll be better off measuring what rear ride heighth I end up with before deciding which size front to rear spacers should get me closest to level, and hopefully only about 2" above stock.
Thanks again.

 

[PitbullRescuer]

Are you running 99 springs in the front too? It'll be damn near level without any spacers in the front if your mating them to 99 rear springs? I ran OME 906's in the back with 10 mm spacers and 99 talks in the front with 1/4" top hats and had a very slight rake.

 

[Dezert4Runner]

The '99 tall's will yield different results depending on the year they're going on. Your '01 will see the biggest gain out of all the years (96-98, 99-00, 01-02).

The top plate spacers are exactly a 2:1 ratio no matter what year you have. A 1" tall spacer will yield 2" of lift, a 1.5" tall spacer will yield 3" of lift, etc on ANY year 4Runner. Period.

 

[Sixpack577]

The '99 tall's will yield different results depending on the year they're going on. Your '01 will see the biggest gain out of all the years (96-98, 99-00, 01-02).

The top plate spacers are exactly a 2:1 ratio no matter what year you have. A 1" tall spacer will yield 2" of lift, a 1.5" tall spacer will yield 3" of lift, etc on ANY year 4Runner. Period.

Thank you for clarifying that.
I know the 01, 02 models sit the lowest in the rear also. That's why I assume the new 99 springs should level it or slightly raise the rear.
I think there was a change in vehicle stability/roll over safety regulations starting that model year.
The lower rear helps prevent roll overs at highway speed.

 

[Sixpack577]

Are you running 99 springs in the front too? It'll be damn near level without any spacers in the front if your mating them to 99 rear springs? I ran OME 906's in the back with 10 mm spacers and 99 talks in the front with 1/4" top hats and had a very slight rake.

As far as I know the front coil overs are stock, as the rest of the truck was 100% stock, one owner vehicle before I bought it.
I'll try again to get a side veiw picture to load.
My rear springs bottom softly on bumpy roads, and have 11 years and 137k miles of sag.
As well as being lower in the rear from the factory in 01, and 02.
I'll take some pics after I put the springs in, and again after I install whatever size spacers.
I'll post them along with several measurements and a link to this thread.
Hopefully the next guy with my questions will be able to find it in a search.
Thanks for the info.

 

[Sixpack577]

I put new Toyota rear 99 springs in my 01 tonight. I used a lift at a friend's shop(so much nicer than driveway gravel and jackstands), it literally took about 15 minutes.
I measured the old springs vs. the new with a 24" set of calipers. I forget the exact height of each(I think it was 16.5" and 17.25"), but the 99's were .75" taller than the stock 01's.
I ended up with 1" of rear lift with the 99's. The 01's were sagging and worn, so that's how I ended up with more lift than the actual heigth difference between the springs.
It turned out perfect. I have one more inch of fender clearance in the rear than the front, and now it sits perfectly level front to rear!
I'll take some pics tommorrow to post before and afters.
I also ordered some spacers. 1" for the front(so roughly 2"), and 2.5" for the rear. I can have the rears cut down if they're too tall.
I just want a couple inches of cheap lift for ease of getting in and out, and a little bumper clearance for getting off and on steep hills.
I REALLY appreciate everyone's help and input on this!
Thank you all!

 

[Gerdo]

http://www.toyota-4runner.org/3rd-gen-t4rs/101871-top-out-spacers.html

 

[3rd gen king]

Correct. It is roughly a 2:1 ratio.

Now also apply to the other spacers.. (y'all are talking about top plate) I'm asking if the 2:1 ratio applies to the "puck" spacers that go about the whole shock. ?

 

[Gerdo]

Now also apply to the other spacers.. (y'all are talking about top plate) I'm asking if the 2:1 ratio applies to the "puck" spacers that go about the whole shock. ?

This applies to the front only. The rear is a 1:1.
A top out spacer and a "built inside" the coil pack will yield about the same.
To get 3" of lift you will need a 1.71" thick spacer.

 

[Joechemist]

Calculate actual lift from spacer thickness

Saw other posts with empirical data but no explanation, so with my background I thought I would provide a reason and a simple equation (eqn). for calculating final lift for a given spacer thickness.

FYI: the lower arm is bound by the ground when not moving but when articulating it puts its energy into the suspension where R= dS/Dw explained below, but we only need to consider the upper A-arm for spacer thickness vs chassis lift.

1. Measure from the upper pivot ball joint to the swing arm on the upper A-arm, this is b2 ( base length for triangle 2).

2. Measure along the same line from upper pivot ball joint to where the shock center bisects the line determined from #1 above. This will be the distance, b1, (base length for triangle 1).

3. Based on the geometry of Similar Right Triangles and a static or non articulating suspension( freeway is not enough articulation so aprox. static) then the equation is as follows: b1/h1 = b2/h2. h1 and h2 will be the heights at the shock and chassis ( or swing arm position).

Example: Static or parked on flat road calculate lift for a 1 inch top plate spacer.

For a 2017 5th gen 4runner approximately measured when static or stopped and/or smooth highway suspension oscillations which are insignificant:

b1 = 5", b2 = 8", h1= 1 for a 1" spacer;

and h2 = b2/b1 x h1,

Plugging in the numbers:

h2 = 8/5 x 1 = 1.6"

For 1" spacer we get 1.6" of lift
For a 1.25" spacer we get 2" of lift
For a 1.5” spacer we get 2.4” of lift; You can measure b1 or b2 length for any similar suspension.

Note: For articulation then need motion ratio, R = dS/dW; S=suspension travel for a given amount of W=wheel travel; we can say d(h1) is approximately equal to dS ; then dh1=RdW; substituting this relationship into b1/h1=b2/h2 and solving for h2 we get the following:

d(h2)=b2/b1 x R x dW

integrating :

∆ h2 =R b2/b1 ∫(0,w)dW or ∆h2=Rxb2/b1x∆W

A dynamic oscillation off road or racing, suspension articulating significantly energy into chassis, chassis popping up and down, this is where spring rate comes into effect with shock dampening.

 

[phattyduck]

Saw other posts with empirical data but no explanation, so with my background I thought I would provide a reason and simply equation(eqn).
fyi: the lower arm is bound by the ground when not moving but when articulating it puts its energy into the suspension where R= dS/Dw explained below, only need to look at the upper A-arm for spacer thickness vs chassis lift. A little rusty so here goes:

1. Measure from the upper pivot ball joint to the swing arm on the upper A-arm, this is b2 ( base length for triangle 2).
2. Measure along the same line from upper pivot ball joint to where the shock center bisects the line determined from #1 above. This will be the distance, b1, (base length for triangle 1).
3. Based on the geometry of Similar Right Triangles and a static or non articulating suspension( freeway not enough articulation so aprox. static) then the equation is as follows: b1/h1 = b2/h2. h1 and h2 will be the heights at the shock and chassis ( or swing arm position). For articulation then need motion ratio, R = dS/dW, substitution and some calculus, for later discussion. S=suspension travel for a given amt. of W=wheel travel and d(h1) ~dS so d(h2)=b2/b1 x R x dW integrating :
h2 =R b1/b2 integral(0,w)dW dynamic oscillation off road or racing, suspension articulating significantly energy into chassis, chassis poping up and down, this is where spring rate comes into effect with shock dampening

For a 2017 5th gen 4runner approximately measured: Static or smooth highway oscillations insignificant.

b1 = 5" and b2 = 8"; therefore, for a 1' spacer we have:

eqn for h2 we get: h2 = b2/b1 x h1, so h2 = 8/5 x 1 = 1.6" aprox.

For 1" spacer we get 1.6" of lift
For a 1.25" spacer we get 2" of lift etc; can measure b1,b2 for any coilover.

The motion ratio of the front suspension is controlled by the lower control arm... Distance from the inner pivot (line between the two bushings) and the outer pivot (ball joint) divided by the distance between the inner pivot and the shock attachment point. That's it, no difficult math...

-Charlie