UCA Installation/Removing the Bolt

What're ya gonna do. You could say that about every component of a vehicle. People that drive with their foot on the brake, low tire pressure, overheating etc. If someone doesn't notice their UCA is loose, they probably wouldn't be changing it themselves. Who knows.

 

Technically bending the body to get the bolt out is wrong as well.

Lifting the cab is the only "correct" answer.

It's a suggestion if he's struggling, it's an alternative method. I've 100% never used it, but I know nearly every Toyota dealer stocks that bolt for a reason.

I've been cooking since 1995, it doesn't make me an expert by any means, but congrats on that odd flex.

 

Given your username, one could assume that you jump out of planes, so I’m going to give you something to think about since I fly for a living.

Would you get into a Twin Otter, King Air, C210, or any other jump platform that had something visibly not installed correctly, say an aileron or an elevator sagging because a cable wasn’t connected properly since the mechanic that worked on it felt that it was much easier to put it back together that way?

I would assume no, because you don’t want to potentially become a smoking hole in the ground.

 

Dat preload tho

 

Odd flex? No

Experience? Yes.

I’m also an aeronautical engineer and pilot, so to me, in my professional opinion, proper installation of components is incredibly important when it comes to any machine.

 

I just did my UCAs and used needle nose vice grips to bend the sheet metal. The trick is to get the pliers as close to the 90* bend in the sheet metal as possible.

 

If I had a PD optimum reserve, I probably would. Your analogy misses the point. It's more akin to slightly underfilling a tire than half assing flight controls. It's serves the same purpose, frontwards or back. Keeping up on your rig is what matters. Point is, it's an alternative method, if homeboy knows the potential pitfalls of said method, let em make up his own mind, you can't pad the walls of the whole world.

 

Wait?!? Why does the direction place any role? It can back out enough to cause a major problem in either orientation.

Yea because the engineer modeled it in CAD and didn’t realize on the computer screen that it would be a problem installing the bolt once the body was on. Since at the factory the UCA bolt is installed before the body it wasn’t caught in ESL builds and it’s not a high wear item that a customer is likely to replace so no one gave it much thought. That’s my opinion anyway.

 

This is the most likely answer. #revit

 

I'll be putting the bolt back the right way. I put spc's on the last truck, but I thought I would try jba's this time. Looks like I need bigger better tools. Here's how it looks so far.

 

All done. A sheet metal vise grip helped. Also a BFH.

 

Jumping on here and this is my 2 cents; it's a common/good practice for engineers and complex system mechanics to orient the bolt to where the bolt goes from the highest point into the lowest point so gravity can hold it for a sec if there was some type of failure of the nut.

That type of practice is normally done on aircrafts though. It gives enough time/potentially hold long enough to correct the issue or get to a safer level. While vibration does back it out, but it shouldn't completely go out.

 

1. hammer out the bolt like my pic above
2. file down the bolt flange so it goes in easier
3. You're doing good. This is the only hard part of the whole lift

 

As moot as this debate is, the bolt in proper orientation isnt going to back out, it just isnt, sure it might slip up a little but the reality is the bolt head gets wedged on the wheel well. It take a long screw driver and hammer to remove the bolt as it drags up the wheel well and there is no legitimate situation other that deliberate use of force to remove that bolt.

 

Duke mic drop

 

Agree, doubt it'll back out or orientation will matter. Besides, that bolt has a ton of side tension on it. Engineers just probably designed it that way as a good practice taught in a lot of technical schools.

The balljoint connecting to the knuckle bolts are not really an issue since it is not considered a "moving" part. Pretty much any object on a bolt that moves using the bolt as the axis will follow that "good practice", if it doesn't there will be a castle nut with a cotter pin attached to it. Honestly though, I have never seen anything go wrong putting it the other way unless its a linkage with no tension on it and the nut back out due to vibration which vehicles don't have...at least none that I am aware of.

Edit/Disclaimer: Again, I am not a Toyota Engineer, but my job is working with Boeing, Military, and Civilian Aircraft engineers for product/system improvements and verification. I was a mechanic by trade and was always frustrated on how some of the bolts were oriented which was why the first thing I asked when I got to my position was the positioning of the bolts.

 

I call BS. By this nonsensical logic, if you put the nut on top then it just wouldn’t vibrate loose in the first place.

Bolts that are prone to vibrating loose get some kind of secondary retainer. Maybe a cotter pin or an interference that prevents it from moving out enough to be a problem.

For every bolt you can find that is “head up” as “good practice”, I can find one equally as critical that is head down.

In this case it could also be an assembly aid for the workers. Because the bolt inserts from the top, the worker doesn’t have to hold the bolt from falling out as they install the nut. Or maybe this assembly is automated (or has some fixture) and that orientation was the easiest.

There are plenty of reasons it could have been done that other than “if you put the bolt in backward you WILL die”. Shit it could have just been done that way cause it didn’t matter at all and the engineer just thought installing from the top made some kind of sense.