Steering Rack Comprison

[Bigunit]

Not defensive...just trying to keep the discussion on track and focused on the opinions of those who actually have the factual basis to give an educated opinion on one of these mounts - the people who actually have one and have wheeled with one & BC, you are not in that group either. I didn't have to break 4 racks to know there was a problem with this component and actually got involved in trying to come up with a "real" solution. That's where I'm coming from.

 

[backcountryislife]

Thanks for everyone's input. I decided the most effective way to do this was "Eeny, meeny, miny, moe".

to be clear... all this is pretty theoretical in nature, it's an interesting physics discussion. ANY of these will be a HUUUUUUGE improvement... get one

 

[backcountryislife]

Not defensive...just trying to keep the discussion on track and focused on the opinions of those who actually have the factual basis to give an educated opinion on one of these mounts - the people who actually have one and have wheeled with one & BC, you are not in that group either. I didn't have to break 4 racks to know there was a problem with this component and actually got involved in trying to come up with a "real" solution. That's where I'm coming from.

It holds the rack... I don't need to study it for hours, own one, or wheel with one to understand that point. It's not a complicated thing. You can make it sound like there's something special about that particular one, and it may be better (likely is from the sounds of it) but it still does ONE thing... hold the rack on the passenger side only.

From the end of having direct knowledge of it, if we're not qualified to talk about the PCF fix, then you're not qualified to talk about how it compares to the others, as you haven't run them in your truck. Do you see how silly that is in the end though... it's a discussion about how a fix should be done, and for you to dismiss the opinions of others for not having run that fix is no better than anyone else dismissing yours for not having snapped 20 racks. Neither invalidates you from the discussion.

Running that one for a couple thousand miles also means almost nothing... unless you were snapping racks before that every few thousand miles, it doesn't prove anything... which gets to the point where this is ALL a theoretical discussion.

 

[Bigunit]

Thanks for making my point.

Sent from my DROID RAZR using Tapataint

 

[silvrzuki77]

4speedfunk... The metal mayhem kit i have on my trick uses UHMV for the bushings but it also uses the stock metal bushings which are unique. Here is a picture I took.

 

[3Hummers]

I actually have enjoyed this thread quite a bit. Spirited and interesting discussion, opinions, multiple products to discuss. Fortunately I have not had a rack break and have not had to study the issue in any depth so the discussion has been both enlightening and entertaining. When I get back to Texas tomorrow I am going to spend some time under the H3. I don't know enough about the products discussed in this thread to choose a "winner" I think they all are an improvement to the OEM set up. It is good to see a variety of people attacking the problem from both a theoretical and practical standpoint.Only good things can come out of this for us.

 

[06 H3]

Kaleb you should of held onto your H3 a bit longer to test this stuff...

 

[4speedfunk]

Jeez, I don't even have a rack & pinion any more! I've broke two racks from all that "internet-wheeling" I do, and its pretty clear what the issue is and how to solve it. I decided to do the "internet SAS", instead of pursuing an "internet fix" for the stock rack.

I hope someday I can go off-road for real!

 

[am4x4]

I gotta agree with BCIL on the drivers-side bushing assessment. You can't clamp one end of the rack rigidly to the frame...and leave soft bushings in the other end. It will eventually push itself apart. We've all seen this. The rack casting breaks right where the sheet metal tube portion gets pressed-on to it...and it starts to separate as you continue to use it. Eventually, it will separate to the point (1/4" to 1/2") where the rigid PS fluid tube cracks and pukes the entire system out on the trail. Its important to note that this separation is not from external forces...its from the tremendous hydraulic pressure inside the rack. The separation occurs because the drivers-side (the casting) is bolted to the frame...and the passenger-side (the steel tube) clamp is worn-out and loose. Internal pressure is what pushes the two pieces apart, and movement between the two mounting points is what allows it to crack in the first place.

What all of these guys are doing with the passenger-side clamp is great...and it needs to be done. However, they are basically reversing the same scenario by leaving the rubber bushings in place on the drivers-side. Now, instead of a sloppy p.s. clamp and firm d.s. bushings....you'll have a solid p.s. clamp, and sloppy d.s. bushings. A flemsy assembly needs to be allowed to either move together...or not move together. Rigidly attaching only one mounting point of such an assembly, is not an option. The two mounting points need to be addressed together...either leave them all bushed...or make them all solid. That's not rocket science...its just basic engineering.

You have an identical situation going on with the front axle bushings. It does no good to replace just the lower crossmember bushing, and leave the soft sloppy ones on the outboard mounts. The three bushings work together, and you need to make them all soft...or all firm. Otherwise, you're allowing a relatively flexible assembly (the axle housing in this case) to be pried and pulled apart from the inside forces. Just like the rack...movement between the three mounting points is what lets the axle push & pry itself apart. Outfitter Design understands this, and I think their axle bushing kit is the single biggest improvement you can make to the stock IFS. Period. (And no, I didn't get paid to say that).

On the rack issue...all of these guys are doing the same thing with the passenger-side clamp, so I don't even see enough difference to debate it. But, I'm all for the guy that includes solid d.s. bushings in his steering kit, because they need to be there. Unfortunately, I'm so confused from the numerous comparisons on this thread I can't tell which guy (or manufacturer) actually provides them.

So who includes the drivers-side bushings? That's where I'm sending my money.

As Silverzuk started, The Mayhem Metal Works kit also includes replacement drivers side bushing but ours are made from UHMW. It is almost as hard as delrin with around 10X the impact strength. Either option will eliminate all movement from the drivers side of the rack.

 

[alrock]

You like to dream big, don't you?

How's the build holding up?

 

[atvspeed4]

Since other companies are stating what is included in their kits can I simply post what is in the Outfitter Design kit and why it was selected? I will be as brief as possible.

 

[backcountryislife]

btw, if you're going to do a fix I've got to say that IMO, the hunner sleeve PROPERLY installed (imo that includes welding it to the U clamp) with a center U clamp will do as much, if not more, than putting an aluminum clamp on one side. Doesn't look as cool though.

I feel where I failed is in that one picky dam word above... PROPERLY. I think had I taken the time to weld it in, it would have done what it was supposed to do (mine fell out due to poor install imo), and taking the time to do the center clamp eliminates deflection. Obviously a wide, machined clamp does a bit more on the clamp end, as it IMO can hold the rack from deflecting a bit more, but even that could benefit from a center clamp imo.

And yes, I do wish I had kept mine from a testing standpoint at the very least, it would have been nice to see what it would have done had I thrown a solid clamp on one side, or had I done the Hunner clamp the entire way I feel it should be done, and go hammer on it.


Now I just bend swaybar links & break brake lines instead because I'm a dumazz & don't measure right!! (hmm... that INSTALL thing again, I'm sensing there might be a pattern here! :emb: )

 

[4speedfunk]

Its important to note that ANY and ALL of these kits are far better than the stock GM mount. I don't think anybody's getting cut down here...all of them got merit. So quit chur typin...pick the one you like best...and buy it!

 

[rascole]

Its important to note that ANY and ALL of these kits are far better than the stock GM mount. I don't think anybody's getting cut down here...all of them got merit. So quit chur typin...pick the one you like best...and buy it!

Absolutely true.

Anyone with a kit. Have you or can you, set up a GoPro or small video camera to capture the actual movement of the rack AFTER the fix? Should not be too difficult to do. Park against the curb and turn the wheels. This will answer ALL the questions of the drivers side movement. For obvious safety reasons, don't get your buddy drunk and ask him to hang underneath while you drive.

 

[backcountryislife]

It would be cool to see some comparison videos of the different setups & how they limit movement.

 

[digglesworth]

ok.... im hesitant to ask this, in fear of jumping in the water with sharks, but here goes.... it appears that the OD kit and the MM kits lock down the passenger side while , I think, the PCF kit stated it allows for a little bit of "float" that was originally designed in by the factory.... can someone briefly explain to me why this "float" that was designed in by the factory and why its an integral part of the steering system...? im a newbie so go easy.... im still learning...

 

[atvspeed4]

Absolutely true.

Anyone with a kit. Have you or can you, set up a GoPro or small video camera to capture the actual movement of the rack AFTER the fix? Should not be too difficult to do. Park against the curb and turn the wheels. This will answer ALL the questions of the drivers side movement. For obvious safety reasons, don't get your buddy drunk and ask him to hang underneath while you drive.

Im not allowed to link to our webpage as we are NOT a sponsor but go on our page and we have exactly that, GOPRO footage showing no movement. Might not look crazy on camera but that is the ledge that snapped my tierod and main leaf spring.

 

[backcountryislife]

Well for one, locking down both sides provides a little more feedback through the steering wheel, I could see it being a bit distracting with the right tires? Mine was on well worn 35's, and the change in feel was VERY minimal, so I didn't see a downside of it myself, but I can see if you had perhaps stiffer street tires (say a 32 on 18's, where much less rubber is present to insulate from the road) where it would be less desirable.

For what we want, that's the only downside I could see.

 

[am4x4]

ok.... im hesitant to ask this, in fear of jumping in the water with sharks, but here goes.... it appears that the OD kit and the MM kits lock down the passenger side while , I think, the PCF kit stated it allows for a little bit of "float" that was originally designed in by the factory.... can someone briefly explain to me why this "float" that was designed in by the factory and why its an integral part of the steering system...? im a newbie so go easy.... im still learning...

I am not entirely sure that they designed the rack to float. My belief is that they used soft rubber mounts to isolate the soccer moms delicate hands from feeling vibration through the steering wheel, The "float" is a byproduct of the soft bushings. By mounting the rack solidly at both ends, both my kit and the OD kit essentially use the frame crossmember as a brace to help keep the steering rack intact. To simplify that further, If both halves of that rack are solidly mounted to the same sturdy piece of steel neither half can move away from the either. An additional benefit of this is a much mode precise steering feel and increased feedback (good things if you are a "driver" and not a soccer mom)

 

[deserth3]

ok.... im hesitant to ask this, in fear of jumping in the water with sharks, but here goes.... it appears that the OD kit and the MM kits lock down the passenger side while , I think, the PCF kit stated it allows for a little bit of "float" that was originally designed in by the factory.... can someone briefly explain to me why this "float" that was designed in by the factory and why its an integral part of the steering system...? im a newbie so go easy.... im still learning...

I'm not an expert here. But figured I'd take a shot at an answer.
The "float" was designed to take up some of the jaring caused my bumbs in the road. Without the float you would feel every bump in the road causing imcreased fatique. Especialy in your hands. In the old days GM used what was called a rag joint. Which was basicaly two flat plates with several layers of cloth between. Thus it's name rag joint.
Also many people think it will feel more like a luxury vehicle if you don't feel every bump like you do in a sports car.

 

[digglesworth]

that all makes sense... thanks guys...

 

[Happy Hummer]

Great thread so far...
Chris

 

[ArtHummer]

Just want to put my 2 cents on it... (Hopefully that will not stir up a hornet's nest :fxd:... again...)

Just to note: I have no experience with the H3 steering rack issue and my knowledge is based on my previous mechanical experience.
I see 2 reasons to keep the rack floating. First, as mentioned above, is to reduce the "jaring caused by bumbs in the road" or "isolate the soccer moms delicate hands from feeling vibration through the steering wheel".
The second one is that (and I don't see anyone talking about) is to reduce the fatigue on the internal steering rack components. I've replaced several racks (not on H3) that where destroyed on inside. If the rack is clamped solid then all of road noise fatigue will go directly inside of the steering rack components, resulting in reduced life of the rack.
There is a reason why shock absorbers are created. The worst enemy of ALL OF THE mechanical part is the constant vibration, and that is exactly why all cars (including all of the high-performance sport cars) have suspension and steering shocks and bushings.

Think of it this way: The softer the absorption - the more softer and comfortable and more reliable it gets. The harder the absorption - the more responsive and less reliable it gets... And when someone designing a car they have to balance between this 2... AND, the BALANCE is the key, not all the way one or other. If too soft - it will become like a boat in storm and will make you sick(not comfortable), and if to hard - it will bump like crazy and you will lose all control (not responsive) on high speed or bumpy road(plus you will loose all of your screws in you car and in your brain)
I worked on few race cars for endurance races, and yes, stiff steering rack will give you more feel of the tarmac, but you have to be NUTS not to have any absorption at all. It will not only destroy the the rack very quickly, but also destroy your hands and you will not be able to hold on to steering wheel after several hours.

Then again, I'm talking about race car and not the Hummer. You don't go as fast and large tires do provide some absorption. I guess only time will tell what design was able to balance it out better.

 

[alrock]

Thanks for the on-topic post. Please note that if this veers off topic those posts will be deleted. We are not discussing vendor reputations, history, etc.

Differing viewpoints is a good thing and discussion is even better. Beating a dead horse, I.e. Saying the same thing over and over is pointless.

 

[digglesworth]

So I take it none of these mounts have been around or Hummers long enough to really see any long term effects like wear inside the rack?