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L400 Upper A-arm problem
Posted: Tue Jan 03, 2012 7:42 am
by monnomania
I have now broken TWO upper A-Arm out of the front suspension. In both cases, the upper ball joint (bolted on with three nuts) have pulled clean OUT of the upper A-Arm. What the hell?
Thankfully, 5 dollar welding is possible in Mexico! Although the whole setup and process was truly sketchy to watch.
Any one ever have this problem before?
Re: L400 Upper A-arm problem
Posted: Tue Jan 03, 2012 9:12 am
by jessef
Can you post a picture please and be more specific?
Are the bolts shearing
Are the bolts just slipping through the bolt holes on the upper A-arm
Any chaffing in the balljoint spacer
If I recall you have a 3-4" suspension lift on there with some front end modifications.
Re: L400 Upper A-arm problem
Posted: Wed Jan 04, 2012 8:16 am
by monnomania
Not sure what is going on Jesse - Since I broke and later replaced the RIGHT upper A arm in Utah, I have been diligent to regularly check that the bolts are tight and not having any wobble and stresses on the A Arm.
I am interested if others have had similar problems or if, like psilosin, I got a dummy L400.
Here you go LEFT side L400:
Re: L400 Upper A-arm problem
Posted: Wed Jan 04, 2012 10:29 am
by jessef
you problem is evident in the 2nd picture
that balljoint spacer is WAY too tall to be in there. the stress is causing the balljoint to knuckle/turn over and put stress on the bolts.
Funny I just helped another person with this same problem. 1" maximum spacer on TOP of the balljoint. Anything more and it will kill the suspension parts.
Whoever did your lift did a great job on the rear but the front end the way it's shown is not meant to go offroad, just for show. Have that spacer cut down to .9 inches and reinstall with new grade 8 bolts and reinforce the a-arm with an additional 1/16" steel plate (drill fresh holes for the balljoint bolts).
The way it is it will break through again and it can be dangerous. Good luck and I hope the repair will last. (good karma going your way).

Re: L400 Upper A-arm problem
Posted: Wed Jan 04, 2012 1:58 pm
by 92pajero
Where can I get a set of balljoint spacers for my 92 pajero so I can lift the front end?
Re: L400 Upper A-arm problem
Posted: Wed Jan 04, 2012 2:51 pm
by jessef
92pajero wrote:Where can I get a set of balljoint spacers for my 92 pajero so I can lift the front end?
pm Paul (plh) on 4x4wire here:
http://www.4x4wire.com/forums/showflat. ... er=1186784
The montero/pajero balljoints are different than L300/L400. He sells them for around $120/pair.

Re: L400 Upper A-arm problem
Posted: Mon Jan 09, 2012 8:34 am
by 92pajero
thanks my friend, I plan on ordering a couple upper joints, hitting the lathe and milling machine to make a set or two, going to use steel so that disimiliar metal corrosion will not occur. The max thickness for the spacer should stay under an inch?
Re: L400 Upper A-arm problem
Posted: Mon Jan 09, 2012 10:52 am
by thedjjack
I would be interested in a set made in steel...
Re: L400 Upper A-arm problem
Posted: Mon Jan 09, 2012 1:09 pm
by jessef
aluminum spacers don't rust. That's why it's used in all makes/spacer kits. There's a template for the Montero/Pajero ones somewhere online.
Re: L400 Upper A-arm problem
Posted: Mon Jan 09, 2012 5:25 pm
by Big-Bird
Jesse, aluminum doesn't rust you are absolutely right. That's because it doesn't have iron in it....however when bare aluminum oxidizes and comes into contact with steel it accelerates the rusting process of the steel parts. This is a huge issue in my field of work in Oil &Gas processing. If the aluminum is anodized it doesn't react as quickly. Stainless does the same thing to normal steel, it speeds up the corrosion process.
Look up Galvanic Corrosion and you will see this a common issue and varies depending on the type of dissimilar metals that are placed in contact with each other.
Re: L400 Upper A-arm problem
Posted: Mon Jan 09, 2012 10:03 pm
by jessef
off topic but I have gone through many vehicles with modified suspension and I have yet to see an IFS A-arm rust when using an aluminum spacer. Usually the rest of the truck rusts first.

With that said, it doesn't matter from a structural/safety standpoint which you use. They both serve identical purposes. I chose to go with aluminum based on the industry standard for that suspension mod. Nothing wrong with using like for like steel.
Re: L400 Upper A-arm problem
Posted: Mon Jan 09, 2012 10:32 pm
by thedjjack
I was just thinking if they are steel I could run a little weld around them (I am planning to do so redesign on the upper control arms at some point in the very near future....
Re: L400 Upper A-arm problem
Posted: Mon Jan 09, 2012 10:47 pm
by jessef
you can but welding there is bad = adds stress / heat and causes crack/fractures vs. bolting on with proper hardware is always the better solution
Re: L400 Upper A-arm problem
Posted: Fri Jan 13, 2012 8:36 pm
by 92pajero
If anyone can help me out with the template for the pajero ball joint spacer I would appreciate it. I was going to use steel due to the simple fact of dissimiliar metal corrosion and no I would not weld onto the A-arm and that is why I want to also fab a plate that will bolt onto the top of the A-arm to add strength and to still allow access to the grease nipple. Once I have a design and a set fabbed up I will post the findings and will produce a few sets if there is a demand for it. I want to eliminate the issue of stress on the bolt holes in the A-arm thats why the additional plate.
Yes I have done many lifts for other vehicles and yes aluminum will cause corrosion and yes it takes awhile, but I take pride in what I do and I do not feel the need to save 5 lbs of weight by going aluminum. If that was the case I would be driving a smart car or something like that.
Kelly
Re: L400 Upper A-arm problem
Posted: Fri Jan 13, 2012 9:51 pm
by jessef
Kelly I posted Paul's contact link/4x4wire in a few posts above. Go there to chat with him. He's not on this board.