Differential drop info

[Ascinder]

Yeah, we just took mine off for Clint and they looked fine. As far as loading though, they are what holds your center section and are the inside fulcrum points for the CVs so, while the majority of the weight and road loads are supported by the suspension and A-arms, there are a lot of moving things at high speeds connected to these brackets. They also support all of the side loads of the center section, and unfortunately, the brackets are actually weakest in that dimension(hence the gussets). Another concern I would bring up is that is very frowned upon(I didn't know this at the time either) in the welding world of offroading that you don't ever put vertical welds in a vehicle. This allows every bump or hit the vehicle takes the opportunity to start and aggravate a crack right up the weld(which is weak to begin with). Like I said, mine were fine after being in there for well over a year, but it isn't when they're fine that I worry about, it's the big question mark of when they could fail. I just think there are a lot of people out there that automatically assume factory testing, quality, durability, and longevity when they get and install these parts. I think it would be in everyones best interests if the people buying them had to sign a waiver stating that they understand the need for a thourough periodic inspection to continue to guarantee their own safety, and hopefully absolve potential sellers or brokers of these of any unnecessary responsibility. They should also have to disclose the same if the vehicle is ever sold to another person who may be ignorant of their installation.

[Ascinder]

How'd you get away with no vertical welds?

[tom4bren]

Aschinder - we'll have to agree to disagree.

I feel that the majority of the load on the diff brackets is rotational around the 4 axle bolts & since it is a rectangular piece welded in, the welds will not be seeing much strain.

Side loads will be virtually nonexistent since the brackets only locate the center section. If there was any significant side loading, there would have had to be some form of offset mounting to the frame in the stock configuration (& they wouldn't have the rubber bushings). Picture standing a book on end - it's easy to knock it over. Now open the cover slightly to spread out the 'mounting' points transverse to the direction of the force being applied - it's much harder to knock it over.

There's some merit in what you're saying about the vertical welds - but not in this application. These brackets as you stated are isolated from the suspension so will not be seeing any of the road induced shock. There will be some but it's just forces from the weight of the pumpkin. The welds are plenty strong to handle that.

After saying all that - I'm an Electronics Engineer, not a Mechanical Engineer but I've had some experience in mounting weapon systems to vehicles in the past and more recently a cantelevered Ground Penetrating Radar system to vehicles. I'm not pulling this 'out my arse' for the sake of argument.

One comment that you made that I have to agree with 100% is that if you have done this modification and decide to sell your vehicle - a signed declaration & waiver is a very good idea.

Trust me - I thought this through quite a bit before I jumped in with both feet. I didn't do it just because Zeus said I should. At the rate I was eating CV boots - the risk was well worth the benefit.

Tom

"Even the "pro" didn't have the gonads to mimic my skills!" Don't go there Dude. 'Welder Guy' is sensitive to comments like that.

[Ascinder]

I have vert welds; they are just small. Check my gallery! Even the "pro" didn't have the gonads to mimic my skills!

So to me it looks like you cut out the lower portion of the bracket just above the large hole and slid it down, then slid in a spacer plate and welded it all in place then ground down the welds near the side of the large hole to provide clearance for the CV cup. That sound about right? If that's the case, it looks like you have about 1" or so less vertical weld than me. I'm sure Clint can take a pic of the brackets to show how I did mine.

Tom, you may want to reread my post above. If you do I think you'll find I'm really not disagreeing with you, the points I made are true, as are yours. I was just trying to reiterate that the brackets are weakest sideways and could've used more support there. You do have a fairly heavy center section that is applying forces to the brackets whenever it moves. Yes the bushings do serve to isolate it so what it actually sees abuse wise we'll never know. I am just saying that vibrations and vertical welds are not the best of friends. Just think of this going across washboard trails and the pounding it'll take. Like it or not that center section is acting like water in a glass getting sloshed around whenever you do any quick back and forth turns. All in all I really do think they'll hold up fine, and I think you already know my comments weren't designed as any kind of attack on anyone out there. More to serve as a caution to get people to realize what I said above. Anytime you have mods like this done, they aren't factory tested, abused, etc. so you need to make sure and check them from time to time. You gave me what I was looking for right here:

I thought this through quite a bit before I jumped in with both feet.

I just wanted to know someone was paying attention to the small stuff too. I see it pretty often on other boards where you get someone with a good idea and some good intentions, but not a lot of consideration goes into "how safe is this to sell to people". I sure that wasn't even remotely the case here, but it doesn't hurt to make sure.

[tom4bren]

I just didn't want to scare anyone away from doing the mod. I agree with your concerns but the drop brackets don't cause more risk for failure than the lift & running bigger meat.

[tom4bren]

"Well, WormGod said to start a fight club! Let's get it on! "

Dude - you can't hang with the big dogs - you have small vertical welds.

[Ldub]

"Well, WormGod said to start a fight club! Let's get it on! "

Dude - you can't hang with the big dogs - you have small vertical welds.

Not to mention a decidedly dainty radius...

[ZEUS]

So to me it looks like you cut out the lower portion of the bracket just above the large hole and slid it down, then slid in a spacer plate and welded it all in place then ground down the welds near the side of the large hole to provide clearance for the CV cup. That sound about right? If that's the case, it looks like you have about 1" or so less vertical weld than me. I'm sure Clint can take a pic of the brackets to show how I did mine.

Drop_Thread I should have just posted this before. I couldn't find any pics of your brackets, but if you did yours like BigMeatVX did his, then you should have twice as much vertical weld because you welded two vertical seams, where as I have one. Like I said in my build thread, both designs should hold up just fine, and I am not worried. It did cross my mind to weld a 5/8" rod inside the radius to connect the 3 pieces together, but I felt it was overkill. Again, USE THREADLOCK!

[tom4bren]

BTW,

Two things that I noticed when I installed my drops:

1. You'll need to extend, stretch or replace the axle vent hose.

2. You need to notch the passenger side on the rear where the bracket curves in. There's a bolt on the pumpkin that'll hit. (I took a pic for JHarris but haven't posted it yet - it's on my laptop so I can't get to it from here - I'll post it tonite).

Tom

[tom4bren]

"The berries are bigger than the twig..."

I have no response to that.

[Ascinder]

Zeus, are you saying you didn't weld the lower sections of your brackets on the sides, just to the 2" portion horizontally?

[tom4bren]

Zeus was able to find a piece of stock with matching curvature (from a jeep bumper). He cut the diff bracket such that he retained the large hole for the axle and the 2 lower mounting bolt holes. This cut piece was positioned 2" lower and the donor piece from the bumper was welded in place to fill the 2" gap. Basically he traded one vertical weld for a horizontal weld (1 vertical & 2 horizontal). That's why he didn't have the interference issue with one of the bolt heads on the pumpkin that I mentioned earlier). His are welded all the way around even though it doesn't look like it in his picture since he ground down the lowest section of the vertical weld.

The way that BigMeat did it (& I copied) was to cut out only the flat center section and replace with new material (retaining the curved areas in place). We ended up with 2 vertical welds and 1 horizontal. IIRC this is the same method that Joe Darlington uses.

Did I get it right Zeus???

[Ascinder]

Ok, how I did mine was just to cut out the area around all four bolt holes and of course the CV hole and slide the piece down vertically, then weld in a 2" spacer. I retained the curvature and meat on both sides of the piece, so I guess mine was a little different than both. The advantage mine had was having all the holes line up flawlessly since they are the factory originals. This saved time laying out and drilling new holes, and I don't end up with extras that go unused. I didn't have to clearance anything either. I'll talk to Clint tonight to see if he'll throw up some pics.

[tom4bren]

I'll mention your method to 'Welder Guy' next time I see him to see if that's a better approach but I think he's already fabricated several sets of blanks for insertion & fabricated jigs for welding. He'll probably just stick with the process he's already used.

[ZEUS]

Zeus was able to find a piece of stock with matching curvature (from a jeep bumper). He cut the diff bracket such that he retained the large hole for the axle and the 2 lower mounting bolt holes. This cut piece was positioned 2" lower and the donor piece from the bumper was welded in place to fill the 2" gap. Basically he traded one vertical weld for a horizontal weld (1 vertical & 2 horizontal). That's why he didn't have the interference issue with one of the bolt heads on the pumpkin that I mentioned earlier). His are welded all the way around even though it doesn't look like it in his picture since he ground down the lowest section of the vertical weld.

The way that BigMeat did it (& I copied) was to cut out only the flat center section and replace with new material (retaining the curved areas in place). We ended up with 2 vertical welds and 1 horizontal. IIRC this is the same method that Joe Darlington uses.

Did I get it right Zeus???

Yessir, you got it. It was easier for me to make those 2 cuts on the original brackets... like butta. Three cuts seemed like too much of a PITA for my lazy PITA.