7500 lb Rated Bags

Firestone came out with some higher capacity springs as well, called Firestone 2705 Red Label Extreme Duty Air Springs, 7500 lb capacity, 150 PSI. I purchased the regular Firestone bags which come with the 5000 capacity but with the weight of my Lance 1172 and possibly a Eagle Cap 1165 I thnk I need am upgrade.

Any suggestions on which route to go for these newer heavier duty bags?

travelnutz wrote:
Thanks for your reply,

Yes as the brackets should be mounted (thru bolted) for maximum strength and durability. Welding the nut on should not be necessary as a good lockwasher should be sufficient. If desired, a second nut can be securely jam nutted against the first nut also. A new bolt is no stronger than that of it's thread root (minor or bottom of the thread) diameter. Un fortunately, welding of the nut to the bolt can cause strength problems because the intense heat from the welding anneals the heat treated grade 8 bolt dropping it's yield strength down to a grade 5 or can even be close to a grade 2. Just for your information.

Never send a boy to do a man's strength job!

Rust preventitive spray painting the bolts on both sides is still wise for longivety. Rust compromises yield and breaking strength and spray painting is so cheap and easy to do. What's the down side?

haven't looked in a while but I believe the shop tack welded the nut to the frame not the bolt. could be wrong. truck is in the shop getting the damage from the car theft repaired so I really can't look.

Thanks for your reply,

Yes as the brackets should be mounted (thru bolted) for maximum strength and durability. Welding the nut on should not be necessary as a good lockwasher should be sufficient. If desired, a second nut can be securely jam nutted against the first nut also. A new bolt is no stronger than that of it's thread root (minor or bottom of the thread) diameter. Un fortunately, welding of the nut to the bolt can cause strength problems because the intense heat from the welding anneals the heat treated grade 8 bolt dropping it's yield strength down to a grade 5 or can even be close to a grade 2. Just for your information.

Never send a boy to do a man's strength job!

Rust preventitive spray painting the bolts on both sides is still wise for longivety. Rust compromises yield and breaking strength and spray painting is so cheap and easy to do. What's the down side?

travelnutz wrote:
Buzzcut1,

The bracket didn't fail, the bolts holding it did!

As rusty as those bolts are, it's no wonder they failed and likely the heads popped off due to deep rust penetration in the inside head to shank sharp corner. Hope you'd spray painted liberally from multiple angles the new bolts with a rust preventative paint or you are likely to see them break off again due to deep rusting. Rusting weakens steel!

Too bad you couldn't use the farther apart mounting holes also because it gives the bracket a wider spaced bolt pattern footprint which lessens the twisting force on the bottom bolts that are trying to be ripped apart by leverage from the bag's top. Just a suggestion from a retired automotive engineer.

New set up is drilled through the frame instead of threaded into the frame, the bolts are a much thicker grade 8 bolt and the nut on the back side is welded into place.

Buzzcut1,

The bracket didn't fail, the bolts holding it did!

As rusty as those bolts are, it's no wonder they failed and likely the heads popped off due to deep rust penetration in the inside head to shank sharp corner. Hope you'd spray painted liberally from multiple angles the new bolts with a rust preventative paint or you are likely to see them break off again due to deep rusting. Rusting weakens steel!

Too bad you couldn't use the farther apart mounting holes also because it gives the bracket a wider spaced bolt pattern footprint which lessens the twisting force on the bottom bolts that are trying to be ripped apart by leverage from the bag's top. Just a suggestion from a retired automotive engineer.

My 5500 is running stock suspension to carry my Arctic Fox 811. We'll see if I need to add upper StableLoads when I load up my Host Mammoth. My truck has flat bed with under deck storage boxes. Once I have the Host, I will address above deck storage under the camper wings.

Bedlam wrote:
Airlift has a new 7" airbag system for pickup trucks with a 7500 lb load rating at 100 psi. I wonder if these would have more or less bounce than the smaller 5000 lb rated bags available. I'm not affiliated with this company and generally steer people away from bags under a truck camper, but others may be interested in this new LoadLifter 7500 XL.

I was going to say, you need bags on a 5500? Quick side question: Is this a flatbed or did you order with a truck bed?

I installed them on my 3500 and even with a pretty heavy set up I only put about 20 pounds on the slide side and 10 on the drivers to level the truck. I have been toying with getting bigger leafs for my truck. The air bags definitely make the tuck floaty/increase swaying.

travelnutz wrote:
I have had Air Lift Systems 5000 lb airbags on every one of my 2500 and 3500 GM pickups since 1993 both for my business and my personal trucks and NEVER had any bounce from any of them. That's what good truly adjustable to the load shocks are for but so many cheap out and buy set load dampening shocks and it's a head scratcher! Like one size does NOT fit all nor all conditions! Good adjustable shocks dampen to almost totally eliminate any bouncing. I have no financial interest in Air Lift at all other than being a very happy well satisfied long time customer.

All truck brands suspension designs are not the same which means different results with using the very same airbags. I have yet to have or see an Air Lift System airbag bracket fail or break and not even on our first which was later sold to an asparagus farmer neighbor of property we own and at over 440,000 miles and 24 years of being on the truck, the bags still are working fine but he sure has beat up the body of the truck and the bed the last 3-4 years. He's run into it with his front loader bucket and dropped gobs of very heavy stuff on the bed. We see the 1993 truck many times a year and are good friends with the farmer/owner. He has a newer truck for personal use now and just uses the 1993 for beat the heck out of it things. O'well, it's his truck and has been for 12 years now so why should I really care what he does with it?

Basically, I wouldn't have a truck carrying a heavy load like a big TC or a heavy 5th wheel pin weight without having airbags. Air Lift System air bags properly inflated for sure and I'm all for the 7500 lb bags as with 5000 lbs on'em, that would only be 2/3 of their capacity! Smart people won't use a boy to do a mans job!

I had the upper mounting bracket fail. the lower two bolts heads snapped off, the upper two held and the bracket itself deformed. Airlift sent me out a replacement bracket at no charge. It does happen.





replacement with thicker grade 8 bolts

Tom_Anderson wrote:

HMS Beagle wrote:

The spring rate of an air spring is proportional only to the height of the spring, and independent of the diameter. That may seem non-intuitive, but it is true. So unless they are taller than their 5000 product, the spring rate will be the same, and the "bounce" will be the same.

7500lb. bags at the same PSI as the 5000lb. bags are going to have a higher spring rate. To get the same spring rate in a larger diameter bag, you won't need as much pressure, which will lower the spring frequency, FWIW.

Personally, I've never noticed the dreaded bounce with airbags and good shocks.

It will in fact lower the spring rate to exactly that of the smaller bag bag. To be clearer, I should have said "supporting a given load" spring rate is proportional to installed airbag height, and independent of diameter. The force is pressure times area, but the rate at a given load is simply the rate of change of volume - and that is proportional only to the installed height. The spring frequency is a function of the rate and supported load - this will also be identical between the two in a given installation. The only way to soften the rate of an air spring supporting a given load, is to make it taller.

I have had Air Lift Systems 5000 lb airbags on every one of my 2500 and 3500 GM pickups since 1993 both for my business and my personal trucks and NEVER had any bounce from any of them. That's what good truly adjustable to the load shocks are for but so many cheap out and buy set load dampening shocks and it's a head scratcher! Like one size does NOT fit all nor all conditions! Good adjustable shocks dampen to almost totally eliminate any bouncing. I have no financial interest in Air Lift at all other than being a very happy well satisfied long time customer.

All truck brands suspension designs are not the same which means different results with using the very same airbags. I have yet to have or see an Air Lift System airbag bracket fail or break and not even on our first which was later sold to an asparagus farmer neighbor of property we own and at over 440,000 miles and 24 years of being on the truck, the bags still are working fine but he sure has beat up the body of the truck and the bed the last 3-4 years. He's run into it with his front loader bucket and dropped gobs of very heavy stuff on the bed. We see the 1993 truck many times a year and are good friends with the farmer/owner. He has a newer truck for personal use now and just uses the 1993 for beat the heck out of it things. O'well, it's his truck and has been for 12 years now so why should I really care what he does with it?

Basically, I wouldn't have a truck carrying a heavy load like a big TC or a heavy 5th wheel pin weight without having airbags. Air Lift System air bags properly inflated for sure and I'm all for the 7500 lb bags as with 5000 lbs on'em, that would only be 2/3 of their capacity! Smart people won't use a boy to do a mans job!