Rear rear axle suspension

[cranetruck]

When the 8x8 was towed from Oklahoma, we suspended the rearmost axle as shown in image below for a couple of reasons, improve turning and to have spare tires available.
We used a chain after the axle was lifted with the crane.

Question: Is there an accepted method to this with some gizmo that will not require a crane or perhaps even a jack?

My plan is to drive with the axle suspended whenever possible to improve fuel economy for one thing.

 

[Offroadfabworks]

r u willing to fab up anything to make it do this??..

 

[cranetruck]

Possibly, if it's an accepted way to do it, don't know about the rules of the road for this....
Maybe a truck junk yard would have something....

 

[Westech]

Well first I would say is it worth the savings in fuel? Second; will the rear suspension be able to move and work as it should? I would think there could be some ill effects with the front half doing all the work and the rear hanging (rebound and compression). I would have to think that chaining up the rear would be the best way to support the axle. Giving it the ability to move a little bit. If you were to use a "bar" to raise and support the rear axle the shock of going down the road my hurt another component. I would think twice about raising the rear axle in order to save on fuel, and keep that to a emergency use only.

 

[Offroadfabworks]

if u raised it i dont think u would wanta do it with anything that would be solid.. as to what Westech said as it could cause a chain of effect.. i guess i was kinda thinking of making a airbag type set up or something can could allow it to move a little bit but yet keep it up outta the way..

 

[joq867]

Try a truck junk yard, look at the tag axle of a tri-axle dump truck. It raises and lowers via a dash mounted switch. Springs raise it for cornering and air bags lower it for more wieght capacity.

 

[Offroadfabworks]

Try a truck junk yard, look at the tag axle of a tri-axle dump truck. It raises and lowers via a dash mounted switch. Springs raise it for cornering and air bags lower it for more wieght capacity.

exactly what i was talking about..

 

[Monty]

You could also look at steerable tag, which would give you the option of leaving it down while cornering. They use them on some tri and alot of quad axle dump trucks.
Cool looking truck by the way.

 

[cranetruck]

Thanks for your responses, I'll do some research. It would only be for hwy use, of course.

Monty, I love that truck, it is great to work on, lots of features, zero rust with all the aluminum, better hp to weight ratio of just about any MV (at least w/o a trailer). I have had many systems taken apart and start to get things together now. Driving it should be interesting.

 

[clinto]

Well first I would say is it worth the savings in fuel? Second; will the rear suspension be able to move and work as it should? I would think there could be some ill effects with the front half doing all the work and the rear hanging (rebound and compression). I would have to think that chaining up the rear would be the best way to support the axle. Giving it the ability to move a little bit. If you were to use a "bar" to raise and support the rear axle the shock of going down the road my hurt another component. I would think twice about raising the rear axle in order to save on fuel, and keep that to a emergency use only.

 

[Cdub]

When towing a heavy duty truck we would pull the axles in the rear as not have the drive train turning when elevated in the front so that parts of the drive line wouldn't turn with out any lube hitting the gears.

The only time we would chain a rear up is when we towed a tractor from the back and would chain up the tandem axle.

Otherwise no......we would not chain up any rear axles unless there was damage to it for some reason.

C'dub

 

[BFR]

obviously this would require scaling up, but wouldn't interfere with the stock suspension when not in use...
http://www.stu-offroad.com/suspension/sdw/sdw-1.htm

 

[73m819]

does the 757 have a power divider for the rear set of axles, is it does then you could airbag it and just thow the power divider out to disconect the two axles from each other

 

[cranetruck]

Yeah Ron, the drive shaft between the axles can be (and still is) removed.
I'm a little concerned about the tires and by being able to suspend this axle, I basically have two extra tires in a pinch. Turning radius should be improved with one axle suspended too. May not effect fuel economy much, though....

 

[ken]

Are the two rear axles connected? Like a 2 1/2 ton or 5ton boogie style set up? If so i would be conserned about the u-joints operating at thier max angles for long periods of time With the rear lifted.

 

[73m819]

if you dont plan on installing the drive shaft between the axles, then the air bag set up that was talked about before would work great, to bad the front rear axle does not have a power divider

 

[cranetruck]

Yes Ken.