Why do our LBJs fail?

[ShooterMcGavin]

I have searched and read... I know it is a design "flaw" and that the joint is under tension rather than compression. My question is more about, what causes a new LBJ on our trucks to fail? ...or do they? Impacts? Side-loading? Carrying extra weight? Lifts, yes, I know that does add to the stresses.

I just replaced the LBJs on my 4Runner. Do I need to be prepared to have one fail while I am out on the trail immediately, or is it something that I don't need to think about for 50,000 or 100,000 miles?

 

[BrianSD_42]

what causes a new LBJ on our trucks to fail? ...or do they?

There is no design flaw. {EDIT - ok so I concede the design is far far from optimal}

Toyota LBJs last 10-15 years and 100,000 to 150,000 miles depending on usage.

I would hardly call that a design flaw.

 

[ShooterMcGavin]

Thanks. That was pretty much what I was getting at. So, it's not necessarily a weaker joint design, right? It just happens to fail in a very unpleasant manner.

 

[BrianSD_42]

At least for OEM that is the case.

There are actually some really good threads on this site where the exact reasons have been discussed in detail.

If you do a standard forum search for keyword LBJ it will not work since the websites search requires 4 characters or higher.

You can use the link in my signature for how to properly search the LBJ threads on T4R.

 

[02SE]

There is no design flaw.

Toyota LBJs last 10-15 years and 100,000 to 150,000 miles depending on usage.

I would hardly call that a design flaw.

Well, if you don't want to call it a design flaw, I would suggest calling it at best a poor design.

To Toyota's credit, they did redesign the LBJ placement on 4th gen 4Runner's, to a much safer installation that places the joint in compression.

 

[Nelsonmd]

Well, if you don't want to call it a design flaw, I would suggest calling it at best a poor design.

To Toyota's credit, they did redesign the LBJ placement on 4th gen 4Runner's, to a much safer installation that places the joint in compression.

Yeah, you can argue at what life length you start to consider something a design flaw, but if the design requires the use of a high spec material, then the design is not robust (yes, that's a real engineering term). Robustness is a very important characteristic, and the reliance on high spec process and materials is a sign of poor design. Sometimes this reliance is necessary because you are pushing the limits of current capability, but that's not what Toyota was doing with their LBJ's. They chose a worse design than was readily available to them. This is a sign of poor engineering, which I would consider a flaw.

I mean, sure the OEM LBJ's pretty consistently last 90k miles, but with a change of design they could probably last 150k or more. Plus, and this is a big plus, with the design change to the 4th gen design, you have a much wider margin for detecting a worn out LBJ before catastrophic failure. In fact, I'm not sure the 4th gen ones even do fail catastrophically. I haven't hung out in the 4th gen forum, but I wouldn't be surprised if there isn't a single case of it.

 

[BrianSD_42]

02SE - I'll agree with that. It isn't the best design ever. In my non-professional experience with cars and car parts over the years I've found that pretty much any car part that is made up of a rubber compound will be suspect after 10+ years of time and use. Maybe it will make it to 15 years but the rubber gets weak and breaks down.

NelsonMD - I was actually going to suggest the OP do a search for the past LBJ articles where you have commented in detail on this subject.

 

[JayRolla]

There is no design flaw.

Toyota LBJs last 10-15 years and 100,000 to 150,000 miles depending on usage.

I would hardly call that a design flaw.

There is a design flaw. They last that long but should NEVER EVER fail to the point where they break at 100k miles causing tire to come off and possible vehicle roll over. When ball joints fail they get a little loose and the boots tear. I have never had a tire come off on any vehicle I have ever owned with the joint flipped and not like how ours is designed. If you look up lower ball joint failure on google most hits are what type of vehicle? Not to mention look how many non 4runner failures are Lexus and Toyota.

https://www.google.com/search?q=low...a=X&ei=lPr-VPXFGPXbsAS05oLoCQ&ved=0CAYQ_AUoAQ

 

[Laidflat]

Balljoints used in tension have been used in a LOT of applications. Pretty much every Chevy 1998 and down truck chassis was this way. Toyotas, nissans, and even mazdas were all used with tension applied to the lower balljoint. So it's not something unique to the 4runners like this forum makes it seem.

However I will say that a lower balljoint is far superior as a compression vs tension design since it always has the weight of the vehicle keeping it together.

 

[allwheeldrive]

The way you guys talk about these, makes it seem like they total crap. Mine are original with 178k on them, no play, no grease leakage. I can understand needing to replace them more often if you go off road, have bigger wheels/tires, suspension lifts, etc. But for a ball joint to last over 100k is not too shabby in my book.

 

[Laidflat]

The way you guys talk about these, makes it seem like they total crap. Mine are original with 178k on them, no play, no grease leakage. I can understand needing to replace them more often if you go off road, have bigger wheels/tires, suspension lifts, etc. But for a ball joint to last over 100k is not too shabby in my book.

^agreed. Every other oil change I check brakes, grease what ever can be greased, CHECK PLAY ON BALL JOINTS and tie rods.

I have never had a balljoint fail in all of the vehicles I've owned.

 

[IBallEngineer]

They fail because they were made from recycled nuclear waste rods and rubble from WWII.

 

[jeremyc74]

There is no design flaw.

Toyota LBJs last 10-15 years and 100,000 to 150,000 miles depending on usage.

I would hardly call that a design flaw.

Yeah, it's a flaw. It would be one thing for them to wear out and get sloppy, but to fail in a way that's as dangerous as these are is an engineering failure.

What would you say if it were an A-Arm breaking in half? Or a wheel?

For a pivot point to wear out is a natural thing. For it to break off isn't.

 

[krenaud33]

Mine are original with 178k on them, no play, no grease leakage.

As far as I know mine are original and if in fact they are they have 300,000 miles on them. I have read about a lot of failures on here recently. The other day I ordered a set to replace mine in an effort to prevent ever having to deal with a dangerous situation due to failure.

I believe it was a poor design.

 

[nevada]

Well, if you don't want to call it a design flaw, I would suggest calling it at best a poor design.

To Toyota's credit, they did redesign the LBJ placement on 4th gen 4Runner's, to a much safer installation that places the joint in compression.

agreed.

There is a design flaw. They last that long but should NEVER EVER fail to the point where they break at 100k miles causing tire to come off and possible vehicle roll over. When ball joints fail they get a little loose and the boots tear. I have never had a tire come off on any vehicle I have ever owned with the joint flipped and not like how ours is designed. If you look up lower ball joint failure on google most hits are what type of vehicle? Not to mention look how many non 4runner failures are Lexus and Toyota.

https://www.google.com/search?q=low...a=X&ei=lPr-VPXFGPXbsAS05oLoCQ&ved=0CAYQ_AUoAQ

as said above, there are many other vehicles using BJ's like these.
suspension shape and design sometimes doesn't leave room to orient them the other way. I have seen many other cars with failed ball joints, that allows the knuckle to disconnect from the control arm, resulting in a loss of control.

but its certainly not the best design....

 

[bufferdan]

I have had two of these runners with over 220k on original ball joints and are fine

 

[JayRolla]

agreed.



as said above, there are many other vehicles using BJ's like these.
suspension shape and design sometimes doesn't leave room to orient them the other way. I have seen many other cars with failed ball joints, that allows the knuckle to disconnect from the control arm, resulting in a loss of control.

but its certainly not the best design....

The flaw is in toyotas design, not entirely on the way its designed. Not sure what they did wrong but it should not come apart on so many toyotas like it does. It is known that this type of joint fails a lot more than others. Which mazda's and nissans also have ball joint failure more than others. I have also seen other cars fail like you said.

But look at the google link. What do you see. Toyota Lexus is all you see. There is a flaw. I have owned many vehicles and only failure like this was on my 4runner.

Im actually doing my buddys lower ball joint that was just replaced last year with an OEM part. He has 3" front lift toytec coils. If the design is okay than maybe its the lifts killing them. Again not the best design.

 

[jeremyc74]

As far as I know mine are original and if in fact they are they have 300,000 miles on them. I have read about a lot of failures on here recently. The other day I ordered a set to replace mine in an effort to prevent ever having to deal with a dangerous situation due to failure.

I believe it was a poor design.

I have had two of these runners with over 220k on original ball joints and are fine

Examples like this indicate that the issue is probably in the manufacturing process, rather than the original design. I've worked in production metal casting, and it's tricky business. There's probably something happening during the process that causes some parts to be weaker than others, but is hard to detect.

But having said that, engineering parts so that it's possible to produce them with high quality is a huge part of the challenge of maintaining the reputation that Toyota has.

 

[D Farms]

i mean the bottom line is they should have never moved away from a solid front axle.

 

[pluton]

i mean the bottom line is they should have never moved away from a solid front axle.

Amen to that. I had two FJ 60 Land Cruisers and then a '91 torsion bar IFS. The solid axle was the best on rough surfaces, but steering was primitive. I kinda liked it. The IFS was just as tough, but travel was limited. My '97 steers like a car, but it is a lightweight compared to the solid.