Without gaskets or seals of some kind, I don't believe you can make a case that that assembly is watertight regardless of torque/preload. And living in New England our vehicles are subject to tons of salt in the winter which certainly hastens the process (although I think they're better lately. Maybe that slurry/brine is a little better on vehicles).

 

As an aside, I had to change the rear springs in my Nissan Frontier cause I broke a leaf. Same driving habits, same mileage, but 2008. Bushings in perfect shape.

Moooooooooooooooooooooooooooparrrrrrrrrrrrrrrrrr.. ........................................

 

Thanks for the info on the hardware. I'll make sure to go OEM when I replace them.

On another note, if I were to drill a hole on the bottom of the frame so as to reach the welded nut (in the event of a breakoff) would that damage the structural integrity of the frame rail?
I don't have a welder, nor the ability to reweld said hole. So it would probably stay open.

 

A hole on the bottom of the frame will not access the nut. I made a window with the right angle grinder on the boss. This is the most common approach. You can then see the nut. If you do this beforehand, you can better apply PB, heat, and get a wrench on the nut so it doesn't break off.

Note after all that bolt discussion I ended up reusing an OEM bolt. I have a Tubur bolt on the other side. Meh.



You can paint it afterwards and it will be fine. If you do that LMK so I can borrow your paint can and do mine.

 

Here is another view. I circled where the nut is.

It looks like Dave is very handy with a grinder. I doubt I could have done it so neatly. I would only make this cut if you absolutely have to in a situation where the welded in place nut breaks loose. That area is a load carrying structural part of the body/suspension system. Dave has shown it can be done and not welded closed without near term problems but I would not leave it that way. For one it allows water, dirt and winter salt to freely enter and accelerate corrosion in that area. The hole also reduces structural strength.

If you want to make it easier to get penetrating fluid on the nut and bolt end you could drill a 1/8” hole about where the dot is on the photo below. Afterwards the hole can be plugged by a dab of caulk.

When you are ready to begin the task apply penetrating fluid every day or so for several days ahead. The longer the better. You should have at least an 18” breaker bar that is ½” drive and a 21mm 6 point socket (Impact socket is best). Jack up the body to get the majority of weight off the suspension. Work the bolt alternately counterclockwise then clockwise to help break it free and clean the threads of the original locking compound and rust. If you are careful and the bolt is not rusted to the bushing sleeve there is a very good chance you will get the bolt out without issues.

Dave: you might consider covering the hole in yours with some quality metal tape that is used for HVAC ductwork. That stuff works great.

 

I drilled 1/8th holes in mine aswell so I could fill them up with pb blaster once a week for 2 months ahead of time before doing my lift.

The holes will not hurt anything. They may even help with drainage. My pockets were filled with rust and fine dirt/debris. They arent sealed off or water tight whatsoever

 

Does not!!

Yeah, I got a little can of POR 15 that's been sitting here for 8 months. I was gonna work on it, it's on the list.

 

Originally Posted by third coast View Post
The hole also reduces structural strength.

[QUOTE=Dave51;3597090]Does not!!

I should just leave this alone but I don’t want people to think they can just add any size hole in anything without the possibility of negative consequences. That can be unsafe. Yes, for all practical purposes if you put a hole in something that is load bearing this does reduce the overall strength of the assembly. To say how much can only be answered with sophisticated analysis, such as finite element analysis. If the part was significantly overdesigned the hole may not have any impact for typical conditions.

I am not an expert in the area of structural analysis or fracture mechanics but my basic understanding follows. If there is anyone with a structural analysis background that can better explain this please do.

For any part that carries a load adding a hole changes how the load is distributed in the structure. The load cannot be supported in the area of missing material that a hole represents. The load distribution changes due to missing material and material adjacent to the hole must support an increased load. This is shown below for a very simplified case. In common terms were lines are closer together the stress is higher. Lines further apart show lower stresses. The load must be successfully carried in all areas of the material or damage will result that can lead to a failure, such as forming a crack or bending of the part. If the material with an added hole can support the higher localized loads under all conditions then all is fine.






The important thing to understand is that adding a hole changes things. The ultimate strength of the part is reduced, maybe noticeably in the application, maybe not. A round hole or an opening with rounded ends is better. An opening with sharp square corners is bad as this concentrates stresses, potentially beyond what the material can take. A good general approach is If you must add a hole in something that carries a load – basically supports or holds something together – make it as small and as round as possible.

Holes are sometimes added to structures to reduce weight. If you are interested in the advantages and disadvantages of that you might search Wikipedia for "Lightening Holes"

 

I just kinda looked at it and said "this looks like a good place to make a hole".

 

OK seriously folks, making windows was not an original idea, as I am not that smart nor a struckshool engineer. While reviewing solutions to that problem, I came across a post by (and gave credit to) ehall, who posted



and stated

https://www.cherokeeforum.com/f2/fro...-broke-210280/

So I figured the dealer must have struckshool engineers so that must be the best ("official") way to do it.

 

I guess I should not be surprised that a dealer service department would do that and not weld it back up. And welding has its own issues if not done correctly. I doubt that would be a Chrysler authorized repair method. It would be interesting to know what the approved approach is. Probably replacing the entire spring mount bracket. I see that Dorman has a replacement available for the right front end bracket. P/N 2216-05571258 for the right side. Mopar P/N is 5014590AA. I found it shown as “discontinued” from some sources and available from others.

Anyway I am sure lots of nut repairs have been done this way without issue so I would not worry too much. I would try to protect that area from rust. Corrosion will accelerate crack formation. Sometime in the next couple of days I will post my rust repair method on my build thread.

 

Well I am surprised that you did not make a comment about ehall's repair because the whole bracket is bent! Look at the bottom, and I don't think that's because of camera angle because the bushings are squashed differently.

 

Or maybe not:



But I made much nicer holes than they did!!

 

Yes, as I said before, Dave you made a great hole. I am not in favor of this but if anyone has to do this and you don't plan on replacing the entire bracket do what Dave did. Rounded ends. Drilling two holes and cutting out between them might be an easy way to do it.

Initially I only quickly looked at the photo from ehall and did notice that the bushing doesn't appear to be clamped tightly. Looking at it again I see what seems to be uneven wear on the bushing. If everything is tight and lined up correctly I don’t think that should happen. The hole is also rusty so maybe the hole was done previously?

Back to structural design lessons: For practical purposes anytime you see something that is permanently deformed or bent that is a part where the load applied exceeded the strength of material. The deformation does not go away when removing the applied force. This is called plastic deformation. If an excessive load is repeatedly applied areas of the part that see excessive stress, such as at a hole, will harden and eventually result in a fracture. Lesson learned – it you come across a bent or deformed part it is a good idea to replace it. A failure might be right around the corner.

 

This can be accomplished with just the right angle grander, but agree with all above stated concerns. IMO ehall's people took WAY too much material off and I believe compromised the integrity of the mount. It's only necessary to take off enough material to get fluids, fire and a wrench in there.