@Brother Les , I considered these before ultimately going with air bags. I did not see their design working well for my intended use, but perhaps I was wrong. I see them like Udsuth78, big bump stops that don't help with ride height, just rebound. Is that wrong?

A primary feature of the air bags that I see over the Timbrens is that the air bags are adjustable to the load on the truck. For example, we had a 32' TT, then a 38' 5th wheel and now a 28' 5th wheel. Each of those has a different pin weight or weight on the rear axle of the truck. We haul rock, concrete, firewood, etc... Each of those has different weights they put on the rear of the truck.

I am not saying the Timbrens don't work well, I just don't see how they are/can be adjustable for the use at the time.

I am getting ready to remove the air bags and the over the axle mounts as the mounts are absolute garbage. I will be moving them to over the leaf springs giving a more outboard support and stable support. If I were going to change things up, now is the time and that is why I asked the questions or expressed my concerns above.

Thanks for your time as always, it is appreciated.

 

These are a 'soft' bump stop that gets that gets 'harder' as the load increase. The first url from my about post, click that and scroll up a little bit and it will explain how they work better than me typing.
The Timbrens is install and forget about it, no more 'adjusting' or airbag psi or airbag sway from side to side. Airbags may leak any where in the system and you must have the pump, etc. With no load on the truck, the Timbrens are not even touching the axle. A little load and it kisses it, more load and rubber will allow more 'fall', but very very good support in the rear (and front if you have on the front, I do not). I have the 'extra' overload springs that came with the truck and the Timbrens will not allow them to even be used as the Timbres hold up so well. The Timbrens stop all side to side and front to back sway. Hit a dip in the road, no bouncing.

Look at the url above and it will show how they work, and they do work as marketed

The Timbrens are above the springs, they stop completely any side to side rocking. These are not 'hard' bump stops, but 'soft' stops that work harder with more or the load that you put on it. Before these my rear was dropping 2-3 inches and the front would be 'light' in the front steering and my headlights shining not fully on the road but in people eyes (people were always flashing their lights at me... until I hit them with the real high beam, sorry to those I blinded. I no longer have these issues

Another 'brand' besides "Timbrens" are ''Sumo Spring" that are also of a rubber type of 'lift' that many truck owners like. Both types are install and never think of them again.

I had thought about airbags over the years, but am really glad that I never went to them. I will stay with these. As said before, I have a 35 foot Forest River Hemisphere with two slides. The rear on my truck never drops more than a inch to inch and a half and I do 'overload' the bed of the truck with camping 'stuff'. I am still when all loaded up more than and inch or so from my 'overload' springs from engaging. I would like to make or buy some type of blocks to install between the upper overload spring and the upper bump stop as they are of no use for me as they are now, the Timbrens work so well.

 

just noticed you have listed location as BoCoMo... boone county? If so, I lived around Columbia for almost 13 years until recently.

 

Actually air bags won't sway side to side. If they do it's because the installer was lazy and T'ed the left and right bags together for 1 fill line, which will push air from one bag to the other with uneven loads or crosswinds

If they are plumbed independently and do sway, timbrens would too in the same circumstances... You still sag 1 1/2" with timbrens? I only sagged 1 1/2" with my 5th wheel loaded before airbags. I could stay at empty ride height with bags now if I choose to.

I don't have the fancy electric pump some use, I just use my bycicle pump since it goes in the back room of the trailer with the kids scooters n stuff. Has held the exact amount of air I set them to back when I installed them

I looked into sumos and timbrens. Too pricey for what they are. Give me the adjustability and proven track record of bags vs overpriced rubber coated dense foam

 

Another plus to air bags is if you have a slightly uneven load in the back of the truck. I have to load a heavy machine on one side of the truck and a bunch of tools on the other side which gives me a slight lean to one side. Simply add 10 psi more to the low side and it evens right out. I installed firestone ride rites and have been very happy with them. I liked the idea of the timbrens ( set it and forget it), but the bags suited my needs a little better.

 

Another vote for Timbren's. Not adjustable but are rugged for tough conditions, ice, shale roads, etc.