Upper A-Arm Problems (Taco/4Run/FJC)

[Redline]

Good post ntsqd.

I like to call things their proper name too, though I admit I don't always know what they are. Your explanation about stub spindle makes me feel better because this is what I was thinking of: live-axles/mono-beams are what I'm more familiar with (not that I know much about suspension or geometry in general). IFS is all new to me.

The tapered part pictured next to the stock ball joint is Icon (my All Pro stuff is not with me currently). I’m glad you see and understand the difference and the problem with the taper.

When I was explaining the problem to the first machine shop I visited on Thursday trying to have a sleeve made for the All-Pro bolts, the guy said something similar about the Toyota vs. USA tapers. He said that the taper wasn't “wrong”, that it was just different, and that not all shops have the correct taper available, saying the taper might be correct for a Ford or something else.

FWIW, the part that the wheel bearing resides in or the stub spindle bolts to, and is bolted to both the UCA and the LCA is properly called an "Upright". Rare to hear them actually called that in the off road world (even by people who should know better), but that is what they are referred to as by most of the rest of the motorsports world.
(When it is a live axle under discussion the equivelent part is a "Knuckle.")
They are sometimes improperly referred to as a "Spindle." A spindle is only the part that the wheel hub rotates around in a non-unit bearing design. Older 4wds with a hollow, bolt-on spindle sometimes have that hollow spindle referred to as a "Stub Spindle."
The parts that fit into the Spherical Bearing are commonly called "High Misalignment Spacers" in the desert racing world, where they came from. In this case they are also a taper adapter.
Call me a nomenclature dork if you want, but I've frequently found in my professional experience in racing and manufacturing that knowing and using the correct terminology cuts out a bunch of confusion.


There is a subtle but very important difference in this picture. Note how the stock BJ stud has a sharp taper between the seating (shallow angle) taper and the OD of the threads?
How many washers are between the underside of the nut and the nut's seating surface on the Upright? One very easy failure mode would be for the nut to tighten against the root of the threads without ever fully tightening the shallow taper into the hole in the upright. That doesn't explain the mis-match in taper angles, but could explain why they spin in the hole(s).
I'm rather surprised at those tapered spacers being made that way. Who made them, All-Pro or Icon? It's not a particularly good design.
Toyota tapers are not the same as U.S. tapers. Consequently getting a correct reamer for tapering a hole to the Toyota taper is not easy in the U.S. without ordering them custom. There are many places that can make such reamers, but they won't be as inexpensive as those for the U.S. tapers.
There is not such excuse when the taper is a male feature on a CNC lathe-turned part. That's just sloppy work on someone's part.

I would be extremely surprised if the Total Chaos parts had the wrong taper. They know how things should go together and I've never seen or heard of them doing it any other way.

 

[cruiseroutfit]

Very intersting...

I'd be interested to see what you find out.

FWIW, my chassis engineering textbook calls the part in reference a "knuckle". Where it gets confusing is a solid axle for example. A 79-97' Toyota front axle has a spindle, a knuckle, and a steering arm, all are separate parts .

The Toyota FSM calls it a "steering knuckle"

Re: Tapers, not 100% on those ones, but the US vs Toyota taper is very subtle, but different, I run across it in custom steering components (hi-steer arms, TRE's etc. 1.2" per foot versus 1.5" per foot. The slop from one in the other unmistakable.

 

[jbs]

Yes, it is a good deal. $399/pair. I think the group buy is still on:
http://www.fjcruiserforums.com/foru...-adjustable-upper-control-arms-group-buy.html

I just ordered mine yesterday. I have a 4Runner (same UCA as FJCruiser); I will install them myself.

That seems like a great price unless their website has a terrible typo on it. Was it $399.99 for a set? When I click on the buy now button the Light Racing A-arms come up as $922.00 for a pair! Group buy is over I assume?

I will be very interested to know how well the tapered end of the ball-joint fits into your FJ steering arm. Please post up what you know here in this thread.

Are you going to install them yourself?

 

[maxama10]

Doc & Ryan,

How much total front lift do you have, about 3-inches or less? Are your trucks level or nose high?

Maybe I just had the wrong guy doing my alignment when I had the stock A-arms. My initial alignment after the OME lift left me with just under 1-degree of caster!

If you guys are at 2.5 - 3.0 with the stock A-arms I need to find another font-end guy (the guy I was using is retired anyway). I would put my stock A-arms back on in a minute if I could get that much caster with my set-up.

On Friday I did speak with an alignment technician at my local Les Schwab (7-years expirence) and he confirmed that they are not able to get new Toyotas back to stock specs after they lift them but they seem to drive okay most of the time. I don’t remember how much caster they usually see but I thought it was only about 1-degree like I was seeing?

Before the idea of making the tapered sleeve I was going to go back to the stock A-arms for now. As long as the tapered sleeve is fabricated and works I will likely go that route and see how the All-Pro arms hold up this time.

There is another factor regarding my caster angle that I just remembered. Due to a slight installation mistake with my OME springs, my front end was sitting lower than the rear of my car. If I remember correctly, a nose low attitude gives a bit less caster than a level or nose high attitude. My 4Runner should much closer to level now and this might help caster with the stock A-arms.

I'm running 884's on my Taco and could only get my caster to 1.1 and camber to eh .8 IIRC.

 

[Redline]

Thanks for the into about the group buy.

I just posted and said I will buy a set IF they have the correct/Toyota taper.

I'm waiting for their response.

Yes, it is a good deal. $399/pair. I think the group buy is still on:
http://www.fjcruiserforums.com/foru...-adjustable-upper-control-arms-group-buy.html

I just ordered mine yesterday. I have a 4Runner (same UCA as FJCruiser); I will install them myself.

 

[Redline]

There you go, about the same boat I was in with the stock A-Arms.

I'm running 884's on my Taco and could only get my caster to 1.1 and camber to eh .8 IIRC.

 

[maxama10]

I don't suppose the 4runner/fj IFS "upright" is different from the Tacoma?

I wonder if the same rings true for the Tacoma with the taper?

Anyone have any idea?

 

[fbksurferjoe]

I have had the TC ones for about 2 years now matched with some king coilovers and havent had a single problem with them. They started squeeking about 2 months ago and a little grease fixed the problem. Took the bolts out and they were straight as can be. I would highly recommend these and i dont remember spending more than 250 for mine but i could be wrong.

 

[maxama10]

I hear from a pretty reliable source who had a stock "upright" and oddly enough a tapered fitting from a TC UCA that the taper matches factory exactly.

 

[Redline]

If the Light Racing A-arms don't have the correct taper and Total Chaos does then TC will get my business.

I hear from a pretty reliable source who had a stock "upright" and oddly enough a tapered fitting from a TC UCA that the taper matches factory exactly.

 

[Ryanmb21]

Doc & Ryan,

How much total front lift do you have, about 3-inches or less? Are your trucks level or nose high?

Maybe I just had the wrong guy doing my alignment when I had the stock A-arms. My initial alignment after the OME lift left me with just under 1-degree of caster!

If you guys are at 2.5 - 3.0 with the stock A-arms I need to find another font-end guy (the guy I was using is retired anyway). I would put my stock A-arms back on in a minute if I could get that much caster with my set-up.

Redline, I don't know exactly how many inches of lift I have but, with 265/70/17 tires I am currently 36 2/3 inches from ground to top of wheel well, when I installed it I was at 37". (side note, only 1/3 inch sag after 20K+ miles)

I had to take my truck to two places, the first place did a "laser" alignment and could only get ~1 degree of caster...he told me to get after market a-arms. My truck pulled left, and the guys on toyota120.com said it was do-able with OME and stock a-arms. So I looked elsewhere and found a much better place called Johnson's alignment, Torrance CA, great place, they do the alignment old school with no fancy electronics, and took quite a bit of time. I searched and couldn't find my aligment specs but I do know the guy I went to "maxed-out" my caster adjustment to get it right. I am happy and will likely keep the stock a-arms. Another note, there is very little clearance between the arm and my tires.

 

[maxama10]

Best place would probably be wheelers, or DSM.

Here is the TC Fitting:

Here it is with the spindle:

From what I can tell after a quick measurement they are both 5* tapers.
You can post these for the guys over at the other forum.

This guy, Toku58, is a mod over on TN and knows his stuff.

-Max

 

[ntsqd]

If the Light Racing A-arms don't have the correct taper and Total Chaos does then TC will get my business.

Brian Kudella doesn't miss much. It would highly suprise me if his parts had the wrong taper.
For some background on Kudella search out info on McPherson Chevolet's "Big Mac" and "Little Mac" desert race trucks. He was the engineer in charge of their design. Did some stuff that was light years ahead of what everyone else was doing.

 

[toku58]

Hey what's up guys! I just wanted to add a few insights.

The grading system of bolts isn't 100% accurate.

We have done testing on so called grade 8 hardware and found that although they maybe marked as grade? They were barely the hardness of a grade 5 bolt. (Counterfeit markings) Bolts from China, and other Asian countries maybe suspect. They do this to increase their profit margin, with no regards to safety.


Grade 8 bolts because of their hardness resist bending or yielding. Because of the hardening process they become extremely strong, but they also become brittle. They more likely will snap before they will bend. But it would take a great deal of force to do this.

That being said.
The mobility of the UCA's and the LCA's are basically the same. The LCA will see most of the load. The UCA's main function is to keep the tire on correct alignment through it's range of motion. The UCA's load forces are more on a horizontal plane.

To produce enough force to Damage the UCA's? More than likely the other components of your suspension exceeded their stress level also.
(This is just a general statement, other factors can make a difference)

Fittings?
As "Max" stated I do have the parts to confirm that the TC fittings are correct. Their taper matches the factory.

All the information that I have read. (I have NO first hand experience) AllPro seems to be made with sub standard materials. But again I cannot confirm this. This is more than likely why they are able to sell them at a lower price. IMHO.

I hope this will helps you guys sort things out.

Good Luck!

 

[Redline]

Good to know the Total Chaos stuff is correct. It does look like that spacer could be just a bit longer to fill the total depth of the steering arm/upright. But it appears there is plenty of contact (certainly more than the Icon part!).

I hope I didn't damage other suspension components exceeding their stress level, but that remains to be seen... maybe I need Jounce Shocks from Light Racing to compliment their A-arms

I do know if the All-Pro A-arms are made from substandard materials, though the bolts did both bend. But just as important as the material is the poor design of the wrong taper to fit the steering arm/upright (Icon too).

snip.......

To produce enough force to Damage the UCA's? More than likely the other components of your suspension exceeded their stress level also.
(This is just a general statement, other factors can make a difference)

Fittings?
As "Max" stated I do have the parts to confirm that the TC fittings are correct. Their taper matches the factory.

All the information that I have read. (I have NO first hand experience) AllPro seems to be made with sub standard materials. But again I cannot confirm this. This is more than likely why they are able to sell them at a lower price. IMHO.

I hope this will helps you guys sort things out.

Good Luck!