drop brackets for caster correction and moves wheel forward

[headhunter]

donut fj80 just used spacers did not cut lip. Tapage OME bushings for 2" and drop bracket 2" for 4" total lift.

 

[landtank]

saying OME bushings are for 2"of lift is being overly generous with what they will provide. I've only seen them work for the stock height heavy springs that OME sells which gives about a 1"lift.

 

[headhunter]

This is why I will check caster after lift and adjust acordingly. Im asuming 2" control arm drop will adjust caster for 2" lift.

 

[Tools R Us]

saying OME bushings are for 2"of lift is being overly generous with what they will provide. I've only seen them work for the stock height heavy springs that OME sells which gives about a 1"lift.

saying OME bushings are for 2"of lift is being overly generous with what they will provide. I've only seen them work for the stock height heavy springs that OME sells which gives about a 1"lift.

It is true that OME bushings on most OME lifts do not provide stock caster numbers. My bet is that OME is well aware of this, they have likely driven/tested/evaluated rigs with their setups? My guess is, their goal is to make a kit that drives well, as long as used/loaded as designed. Once suspension and tires are changed, the “best” alignment numbers change, so what worked great on a soft suspension/tire stock rig is pretty much irrelevant, they are likely also aware of this.

As Slee has said hundreds of times, “once lifted/modified they are all different”, my experience agrees. They can’t be the same, too many variables, lift height, weight, where the weight is, the amount of body roll, tire construction/stiffness, driver preference, etc, come into play when evaluating the alignment for best handling. In my experience, shooting for the numbers that worked on a stock rig is often a great way to induce vibrations, often unnecessarily. I have setup/driven lots of rigs with less than “stock spec” caster that drive very well, comfortably, have also seen some “problem children” that required more, but they are the minority.

 

[cody c]

thats a great idea, this would also be of benefit to those swapping in other motors, for more oil pan clearance, any issues with the steering alignment or anything? Im thinking a set of those might work well for me (running between 3.5"-6" lift, depending on the day), as with the increased downward angle of the arms, the front axle moves rearward slightly which this would compensate for, for me I would prefer to widen the distance between front and rear axles.

Whats the chance your selling them?

 

[landtank]

It is true that OME bushings on most OME lifts do not provide stock caster numbers. My bet is that OME is well aware of this, they have likely driven/tested/evaluated rigs with their setups? My guess is, their goal is to make a kit that drives well, as long as used/loaded as designed. Once suspension and tires are changed, the “best” alignment numbers change, so what worked great on a soft suspension/tire stock rig is pretty much irrelevant, they are likely also aware of this.

As Slee has said hundreds of times, “once lifted/modified they are all different”, my experience agrees. They can’t be the same, too many variables, lift height, weight, where the weight is, the amount of body roll, tire construction/stiffness, driver preference, etc, come into play when evaluating the alignment for best handling. In my experience, shooting for the numbers that worked on a stock rig is often a great way to induce vibrations, often unnecessarily. I have setup/driven lots of rigs with less than “stock spec” caster that drive very well, comfortably, have also seen some “problem children” that required more, but they are the minority.

I'm going to disagree with most of this. Any 80 regardless of what springs are used at any given height over stock will require a given amount of caster correction. Throw in all the erroneous variables you want, but the resulting correction will be dependent on the lift achieved.

 

[cody c]

I'm going to disagree with most of this. Any 80 regardless of what springs are used at any given height over stock will require a given amount of caster correction. Throw in all the erroneous variables you want, but the resulting correction will be dependent on the lift achieved.

What part do you disagree with?

Personally, my cruiser had the front end of the brackets on the axle cut, and a pie shaped "spacer" welded in to adjust the angle.

My cruiser is also air-bagged, so I often drive it at different heights, its got a slow leak so I pressure it up to around 45 psi in the front and 40 in the back, via the onboard compressor and paddle valves every morning.

I keep it a little lower for highway travel, and maybe a little taller if Im just going a couple miles to home depot and back. My point is I get to drive at different heights on a daily basis, and for me I find there is a fair bit of range where it drives decently before I can feel the castor, although with 37's it does tend to pull a little with the ruts of the road anyway

I would guess that toyota had considered this to some degree, as the vehicle would drive at different heights empty with one driver than it would with seven passengers and a couple hundred pounds of gear in it. Or in other words, you would think they engineered the landcruiser to drive pleasantly enough within a certain range of castor.

Obviously not many lifted cruisers will sit at exactly the same height, as pertaining to castor correction made by the aftermarket, but there should be some tolerance to this by the design of the suspension.

 

[Tools R Us]

I'm going to disagree with most of this. Any 80 regardless of what springs are used at any given height over stock will require a given amount of caster correction. Throw in all the erroneous variables you want, but the resulting correction will be dependent on the lift achieved.

I agree that lifted rigs need caster correction and that lift height is one factor that needs to be considered.

One case would be my rig, lifted ~5", custom arms with about 7 degrees of caster rolled in. At one time I had/ran two sets of tires, Nitto 295 and Cooper 37". With the Nitto's it was fine, steering slightly heaver than I prefer, but mostly good. With the Coopers mounted it is significantly changed, noticeably heaver. The Coopers are hybrid construction, 3 radial ply & 1 bias, stiffer, taller, so change weight transfer, likely a combination of those and other factors that account for the change. Anyway if/when I make another set of arms, they will have a couple of degrees of caster rolled out.

Stiffening the suspension, tires, raising the center of gravity, lifting the rig, fundamentally changes the handling dynamics, making stock settings obsolete. Simply applying a math formula from an obsolete stock number to all lifted rigs is short sighted. Vehicle handling dynamics is a complicated subject, would take a book to scratch the surface, luckily there are several good ones, reading one may help?

 

[landtank]

What part do you disagree with?

the fact that these trucks as so different from truck to truck that at the same ride height they will need completely different caster solutions.

It just hasn't been my experience at all.

 

[cody c]

Does the OP have any intentions of making a few sets for sale?

Also, how come nobody does a cut and turn like on a 60 axle? Sorry to hi-jack the direction of things, but it seems like you would have decent pinion angle and could get the castor where you want it without having to use spacers, CC bushings, or build arms.

 

[Tools R Us]

...
Also, how come nobody does a cut and turn like on a 60 axle? Sorry to hi-jack the direction of things, but it seems like you would have decent pinion angle and could get the castor where you want it without having to use spacers, CC bushings, or build arms.

Look at the setup of the diff, arms and tie rod, there isn't much room to move anything? There would be if the tie rod were moved to the front, but if going to that much effort, there are lots of possibilities.

 

[cody c]

oh yeah, rear tie rod near the pinion, forgot about that.

 

[headhunter]

CODY C not planning on selling but anyone with basic fab skills could do this probably not $10 in material the rest is just doing it. You could make the paterns cardboard woks fine and get someone to cut and weld for you shouldnt cost much.

 

[Tapage]

what I found in my experience it's the 80 series can be driven and it can do it pretty nice even with low caster .. and that does not happen the same in my 60 series that need much more caster ..

 

[headhunter]

Just thought Id post up that these have worked great probably 5,000 mi and no problems at all.

 

[-Spike-]

the fact that these trucks as so different from truck to truck that at the same ride height they will need completely different caster solutions.

It just hasn't been my experience at all.

I realize this post is a couple of months old, but I thought it begged attention anyway.

I believe what Kevin is saying is that the 80 may behave differently when lifted with the caster numbers at OEM spec than it does at stock height. The truck may ride/handle better with less than 'optimum' numbers. I don't think he was saying that every 4" lifted 80 needs different caster specs, rather that the best ride might be had with different numbers at different heights. People are obsessed with getting the axle back to stock caster specs, when they might be better off shooting for different numbers. Tires and load might also affect handling, so those can probably change what the best final caster numbers might be.