Air bags that work with gooseneck hitch

[Will L.]

Yes front to back is correct. Just be aware that where it stops adds stress to that area.

Places like "gmupfitter.com". The info on frame mods dos and donts. That is the kind if shop owned btw. Some basic stuff, some psycho projects.

Any round tubing that you deal with make sure it is DOM or drawn over mandrel. Under no circumstances use anything that is a seamed pipe or tube for that application. It is stronger than using a box or rectangle tubing, but once again it is applying all of its torque to the steel that it connects to. One of the big mistakes a lot of people make is in trying to strengthen and stiffen up the frame and unless you build a complete tubular chassis frame, it has got to have twisting and torsion points in it or else it will break.

It is all very doable just take the time to do the research first.

 

[SnowDrift]

I've not loaded them up yet, really. I will be doing so in a few weeks, and will have a really good opportunity to give them a performance review.

In terms of the bigger bag the better the ride, this is probably technically true, but I think you'll be splitting hairs on this and it is doubtful you'll see any noticeable difference between the ones you're looking at, vs. another brand. You're only running 5-10 psi in them while unloaded, anyhow, which shouldn't affect the ride at all. I believe this is just to keep them from collapsing in some fashion and maybe to keep contaminants out, if a small leak should occur.

Check with them and be sure they're for the heavier trucks like ours, too, and not just the 1500 frame. The bolt pattern for the bump stop is different.

What I do not like about those in the link you gave is that it appears they're depending, fully, on the lower flange of the truck's frame to take the load. While this would be fine if it was a beam, it's a channel design. That's the reason I made my brackets the way I did, so that I've, essentially, boxed this area. The boxing I did isn't for stiffening the area, longitudinally, as much as it is for preventing the flange from bending under load. The web is resisting the load on the outboard side, but the inboard side has nothing, unless material is added to tie the flanges together.

Tube would be a "torque tube" if you're planning to attach your hitch to it some way in that it would tie directly into the tube and it would be your structural member. If not, then I fail to see the advantage. Your ball transfers the torque to the head plate, which transfers the moment to the 1x2" rails that straddle your frame. The torque/weight in your ball load is resisted by those bars. It is very possible to add a lot of steel and gain nothing in strength, so to speak.

Torque tube does nothing for your bags, either, unless you're just trying to tie them together as another cross member, unless I'm missing what you're saying. If that's the case, then your exhaust might get in the way up over your axle. Square tube would be easier to find and higher quality material than pipe, as Will mentioned. Just turn it at 45 degrees to keep stuff from sitting on top of it, rotting it out. I wouldn't bother with any of this, though. If you need to go through all this, I'd consider a different chassis to do the work, such as a medium duty or a semi.

If you can find a fab shop, I'll gladly send you my design if you want to use the same bags I had. I still have the 3D files somewhere, and all the detail drawings.

 

[schiker]

I am guessing torque tube to resist the frame "ladder" from twisting. As in engine, brake, curve, body roll, and uneven ground twisting from the added weight.

 

[SmithvilleD]

Yes, definitely agree on the boxed upper mount being better - believe the Firestone Ride-Rite kit's upper mount is similar to what you made.

I had considered removing a leaf or two, if it looked like the bags I get are durable enough to trust with a portion of the weight when the truck's empty. The bags I'm looking at are supposed to be 8.5" diameter & I believe the 3800 in their name is supposed to relate to 3800 lbs each, as compared to the Ride-Rites (& others) 2500/2600 ratings. Not that I need the 3800 lbs rating, but it might could be made to ride better, carry/control the weight I want, and not cost notably more than the other kits. Still doing my due diligence to sort out what's what.

Regarding the torque tube idea, I'm basically trying to better understand the reasons why the newer trucks all seem to incorporate one (often bent to clear exhaust, etc.) over or just ahead of the spring mounts. And if incorporating one would have some benefit. Can see any additional stress it puts into the frame rails needs to be adequately spread out into the rails.

Your point is well taken, regarding adding steel/weight possibly without significant benefit. That's why I'm studying this.

A while back I bought an '04 K2500HD gasser truck rolling chassis primarily for it's 14 blt/10.5 with the newer truck's disc brakes. Sold the frame to a rebuilder firend which made the parts I kept free, but kinda wish I had studied the bare frame a little more.

BTW SCHiker - I made it up Half Dome in June - Yosemite is truly amazing. Also hiked up, then bushwacked a bit, to stand right under Upper Yosemite Falls, with the water cascading down from ~1400 ft above us.

 

[SmithvilleD]

gmupfitter.com does look to have some good, common sense info in the "Best Practices" manuals on frame mods. Believe I can press bend some pieces for some reinforcements I do - or at least the upper bag/frame mount/additio, so it has gradual bends instead of the square edge I'd get from just welding similar thickness material/plate on the inside of the frame to box areas.

Don't know if there's a practical way, except plate/boxing for the up/down frame bend sections like the kickup behind the cab. Can imagine a good bit of flex originates there. Know they often bend there in crashes. Don't think I understand enough yet about any negative effects I might cause by boxing that section, so will keep studying/inquiring.

 

[SnowDrift]

These bags worked out great. I put 80 lbs. in them and was loaded with our slide-in camper, tandem axle trailer and two four wheelers. My gross weight with a near empty fuel tank was 13,200 lbs. The bags made a big difference, kept us level and helped with control on the nasty highways. The ride was great, as well. It rode much better than our Grand Prix.

 

[natashajohny]

PAC-brake air bags and b&w goose neck hitch...no interference.