Is that normally where the shock is attached on the 40? I don’t recall them there when I owned mine?
Rear FJ60 Air Lift / Boss Air Bag Install
- Thread starter wngrog
- Start date
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- Thread starter
- #122
Early 40’s. Yes.
Ah. I had a 1977.
So, with the measurements I gave above. 38.5” front, and 37.5 in the rear. How do I assess the height of my lift?
Thanks.
So I have a saggy rear end I need to address, and I am ready to do this, but Boss is not currently available at Slocruisers. The kit is still on the website, and you can order it online, but they don't actually have them, and don't really know when they will. They quickly caught the error and refunded my money, but no air bags.
Any other sources? Any experience with the Firestone kits?
Any other sources? Any experience with the Firestone kits?
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Adding my two cents because I was going to post a seperate thread abort it this week.
I’ve had my boss airbags kit for about two years and I’m starting to see some issues with it.
- One of the ribs on the bag has developed a crack despite always being filled to 35 PSI. So this is indicative of dry rot in my eyes. Still holds air but now I’m not sure how long it will do so
- The other bag won’t hold a seal (the instructions specifically tell you NOT to use gasket seal material between the bag mounts for some reason) and now I need to hunt down the leak and try to seal it. It went from a slow leak over the course of a month to literally running empty overnight.
Overall it’s quite annoying that for that you pay 500 dollars for a hardware failure two years in. If I was to do it again or redo it now I’d definitely get new beefy rear leaf springs and call it a day. The dry rot really is unacceptable, and I’m going to see if they’ll send me a new bag
I’ll upload a few pictures this week before I attempt to seal the bags with silicone tape and flexseal
I’ve had my boss airbags kit for about two years and I’m starting to see some issues with it.
- One of the ribs on the bag has developed a crack despite always being filled to 35 PSI. So this is indicative of dry rot in my eyes. Still holds air but now I’m not sure how long it will do so
- The other bag won’t hold a seal (the instructions specifically tell you NOT to use gasket seal material between the bag mounts for some reason) and now I need to hunt down the leak and try to seal it. It went from a slow leak over the course of a month to literally running empty overnight.
Overall it’s quite annoying that for that you pay 500 dollars for a hardware failure two years in. If I was to do it again or redo it now I’d definitely get new beefy rear leaf springs and call it a day. The dry rot really is unacceptable, and I’m going to see if they’ll send me a new bag
I’ll upload a few pictures this week before I attempt to seal the bags with silicone tape and flexseal
Reedo311
SILVER Star
@DickM, did you order this special directly through Boss? What u bolt flip kit do you have? I’m looking to do this and have the 4Plus flip kit.
I suppose cutting the ubolts is required to avoid cutting/puncturing the bag?
Thanks, P
- Thread starter
- #128
Any chance your exhaust cooked it?
Yes, through SloCruisers from Boss.
4 Plus
No, the u bolts terminate below the round part of the bracket, but above the flat bar, so the trimming is a clearance issue between the two plates.
Sorry to hear you are having a bad time of it. I just pulled tires for rotation and to catch up on some rust repair
inner wheels at the back. Got a chance to remove the air valve so I can do an airline reroute as well. I did a visual
inspection of mine, they seem to be 100% today. I have a close proximity exhaust, as can be seen from earlier
pictures. I'm running between 8 - 15 psi which seems low to me too, but it sure works.
Maybe put up a couple of pictures so we can see what you are dealing with. I would think that local dealer for BOSS
would come forward with a quick warranty on these if they are going away on you.
I have a custom exhausted piped in on my rig, so it has plenty of clearance. Additionally, the crack is on the bottom rib of the bag, on the opposite side of the exhaust.
I was really hoping it would be something as easy to blame as the exhaust
I’ll get the truck on a lift Saturday and upload pictures, I’m going to try and use the silicone tape and flexseal to cover it
^^^
Ah! Silicone tape.
Ah! Silicone tape.
I ran mine pretty hard on and off the road. They leak over a few weeks time but are otherwise still good. Had them for over years.
Hell yeah man I bought mine after reading about your experience with them.
Did some wrenching today where I had the rig on a lift. There’s a rot ring that circles the lower below of the bag - only managed one good picture but it shows it well
Zoom in on my thumb
Others had cracking of the rubber?
Could lead to pregnancy.
Could lead to pregnancy.
I installed mine on Feb 23th and haven’t added air to them once since.
Rubber + oxygen = dry rot. Every time.
It can be delayed, but never prevented.
I don't think you can reasonably expect rubber springs to be immune to that. Tire manufacturers build in some waxes that will come to the surface and form a barrier when the rubber flexes. I would expect air springs to be the same. That's consistent with where you see the rot starting - i.e. in an location that doesn't flex much.
Air bags are a wear item. They provide performance and flexibility for varying load conditions that would be difficult to achieve with a steel spring, but it comes at a cost in durability. They are a wear item just like tires, hoses, belts, window seals, etc...
It can be delayed, but never prevented.
I don't think you can reasonably expect rubber springs to be immune to that. Tire manufacturers build in some waxes that will come to the surface and form a barrier when the rubber flexes. I would expect air springs to be the same. That's consistent with where you see the rot starting - i.e. in an location that doesn't flex much.
Air bags are a wear item. They provide performance and flexibility for varying load conditions that would be difficult to achieve with a steel spring, but it comes at a cost in durability. They are a wear item just like tires, hoses, belts, window seals, etc...
Update: Been a year since I put the Boss bags on. Been on three big trips, last trip over 9000 kilometres to
Tuktoyaktuk and back with lots of backroads in between. Hell, the highway to Tuk is a backroad!
On day one my winch motor failed, it drives my air compressor. Warn 9500 compressor winch. Didn’t know it
had failed until I started to lose air in my right rear airbag. Got to Dawson City, tried to troubleshoot it but my modified
bumper didn’t allow the cover to come off the winch. BIG slap in the head for not doing this correctly first time!
Got to Prince George visiting PG45r and his experience sent me to the fittings. By this time I was stopping at every fuel station for air. Fully loaded 60, heavy! Ironically I could not even buy a bicycle hand pump anywhere which would have worked just as well. So I pulled the plastic line, trimmed them all and brushed on a bit of liquid Teflon for each inserted fitting. Problem solved. But running 15 lbs has made this truck far nicer riding and handles all the nasty stuff much more lively. The Sumo springs up front are obviously seeing action but no signs of wear or tear. So after one year A+ for airbags and Sumo springs working together. I have another trip for 3 weeks into the interior and with new winch motor and everything cleaned up should be good
Tuktoyaktuk and back with lots of backroads in between. Hell, the highway to Tuk is a backroad!
On day one my winch motor failed, it drives my air compressor. Warn 9500 compressor winch. Didn’t know it
had failed until I started to lose air in my right rear airbag. Got to Dawson City, tried to troubleshoot it but my modified
bumper didn’t allow the cover to come off the winch. BIG slap in the head for not doing this correctly first time!
Got to Prince George visiting PG45r and his experience sent me to the fittings. By this time I was stopping at every fuel station for air. Fully loaded 60, heavy! Ironically I could not even buy a bicycle hand pump anywhere which would have worked just as well. So I pulled the plastic line, trimmed them all and brushed on a bit of liquid Teflon for each inserted fitting. Problem solved. But running 15 lbs has made this truck far nicer riding and handles all the nasty stuff much more lively. The Sumo springs up front are obviously seeing action but no signs of wear or tear. So after one year A+ for airbags and Sumo springs working together. I have another trip for 3 weeks into the interior and with new winch motor and everything cleaned up should be good