4 wheel steering on a deuce?anyone done it?

[jesusgatos]

Here's the reply I got from PSC about adding full hydro steering on a deuce:
Full hydraulic is not legal or recommended for the street. You may be able to set it up with a Servo instead of an orbital valve and keep it street legal. The servo basically goes inline between the steering gear and the steering wheel and keeps the mechanical linkage thus making it legal. You will have to fabricate brackets for the pump and cylinder mounts.

Kelvin Jackson
PSC Motorsports
817-270-0102

Makes sense they would say that because of the tremendous liability involved, but look into this for yourself and you'll find a surprising lack of evidence to support the common misconception that full hydro steering is illegal.

 

[mudguppy]

Cylinders in series works but need to be double rod where the rod end flow of one cylinder matched the cap end flow of the next cylinder. ...

normally, yes, but not if the cylinders were oriented to keep the respective rod / cap end relationship.

... A mechanical linkage would bind up when under articulation. ....

no, it wouldn't 'bind', but it would change the aligned steer relationship of the two rears slightly. but, like you said, this is for off-road; on-road wouldn't see near the articulation and resulting variances in alignment.

... I don't see why a parallel hydraulic circuit would not work. It's only used off road at low speed. ....

because there is nothing preventing pressure on one side of the circuit (i.e. on one axle) to back flow into the other and change the steering angle of both axles in the opposite direction.

Makes sense they would say that because of the tremendous liability involved, but look into this for yourself and you'll find a surprising lack of evidence to support the common misconception that full hydro steering is illegal.

 

[Unforgiven]

Here's the reply I got from PSC about adding full hydro steering on a deuce:
Full hydraulic is not legal or recommended for the street. You may be able to set it up with a Servo instead of an orbital valve and keep it street legal. The servo basically goes inline between the steering gear and the steering wheel and keeps the mechanical linkage thus making it legal. You will have to fabricate brackets for the pump and cylinder mounts.

Kelvin Jackson
PSC Motorsports
817-270-0102

That would be the legal-ease answer for the front steering. I do not think it would apply to a securely pinned rear-steer-off-road-only setup. The current stock setup bounces all over the place as it is. The evidence being my open jaw when I first saw those tandems in the side mirror dancing around under an empty bed. I don't think a few millimeters of play due to some extra tie rod ends is really going to be that crucial.

What about some type of electrically driven rack&pinion setup attached directly to the axle housings and clamping to the tie rods? Like a worm gear? Or two separate hydraulic circuits run to isolated rams with some kind of one-way valves at the pump to keep them separate?

Remember this is just a thought experiment.

Thanks Mudguppy. You bring up things that I never thought of.

 

[gunner01]

has anyone heard of this:
my unc was talking about a "cheery picker"tractor?i guess
neway he told me that it has a box u mount in the floor and has 3 setting
lever in first position:turn front tires to the right and the rear will go left
lever in second position:all four tires turn the same direction
lever in third postion: just front steering
is this real or wat(my unc is 70 and this is based off his memory)

Guys this is really old technology. the monster trucks have been doing this since the late 70`s.... also the valve body you need for opposite steer,crab steer and straight steer is readily available at any equipment sales location that deals with telehandlers,ie; Cat,Gehl,JCB,Skytrac,etc.....

 

[Unforgiven]

Yes, the technology is out there.

But we're talking about steering both the rear axles at the same time plus keeping it street legal.

I would further add that such a modification should not limit the articulation of the rears, nor reduce the payload rating via a re-engineered suspension.

Monster trucks are single-axle and trailered to the destination.

 

[Unforgiven]

Jesus,

How about this: a dual, full-hydro steering with a separate ram for each rear axle.

Bolted to each tie rod is an old-fashioned manual rack-and-pinion unit that is bolted directly to the axle housing. Any lightweight application would do, Ford, Chevy, etc. They can be had for about $100 new. There are even lightweight billet units out there for racing applications.

The 2 rack-&-pinions are connected to each other by a splined driveline (nothing big, just enough to keep the axles in synch) to allow for independent articulation of the axles. One of the pinions would have to be driven from the front side. So some modification would be necessary. Something like this would work. It's already set up to flip the pinion (at least that's what it looks like)





The hydro actually does the steering. The rack-&-pinion simply links the two axles together so they do not become out of synch angle-wise.

It sounds doable & relatively cheap. And it solves the Mudguppy paradox.

Different turning radii might pose a more creative solution.

 

[jamesfrom180]

Cool thought Unforgiven,
But the rack still has to transmit the load of the hydro to the tie rod. Unless I'm missing something the lightweight units would not work.

I was thinking that you may be able to have a drag link set up say a pitman arm with four holes. Two for drag links to knuckles, one for a pivot point, and one for the ram. This would allow full articulation I believe.

 

[bigford]

I have 5 tons with rear steering under my F-700. It has an electric / hydraulic power source with a toggle switch for left / right. It has a small pneumatic cylinder that drives a 1" pin in and locks it for road use. If you want I'll send some pics. Front and rear are not connected in any way.

 

[jamesfrom180]

Bigford,

Question was about tandem axles on the rear of a deuce or 5 ton. I still think pics of yours would be cool.

 

[jesusgatos]

I have 5 tons with rear steering under my F-700. It has an electric / hydraulic power source with a toggle switch for left / right. It has a small pneumatic cylinder that drives a 1" pin in and locks it for road use. If you want I'll send some pics. Front and rear are not connected in any way.

Of course we want to see pics.

 

[Unforgiven]

I have 5 tons with rear steering under my F-700. It has an electric / hydraulic power source with a toggle switch for left / right. It has a small pneumatic cylinder that drives a 1" pin in and locks it for road use. If you want I'll send some pics. Front and rear are not connected in any way.

That would be great. Thanks.

While you are under there with the camera, please make sure to snap several pics of the 1" pin. I've never seen how that was done.

 

[bigford]

I'l take some tonight.

 

[bigford]

Hopefully these will load. Basic stuff here. Just a 12 volt electric / hydraulic pump, 4-way solenoid. Small pneumatic ram to drive the pin. Standard 5 ton steering arm with the hole squared up and the guides welded on. Pin hits the center every time.

 

[bigford]

Ok. Here they are. Donor truck was a 1952 M51 for most of the parts.

 

[mudguppy]

how are you running the rear winch?

 

[Kohburn]

That pin location makes a lot of sense

 

[jamesfrom180]

very cool!!! exactly what I was thinking of.

 

[bigford]

You have a good eye mudguppy. The winch is going on front when I get the bumper / mount finished. I needed a place to store it out of the way. I plan to drive it with hydraulics as I may not have any help if (when) I get it stuck. That may cut the pull a little but I will not weigh anywhere close to an MV 5 ton.

Thanks for the compliments on the steering. I used this setup on another truck I drove on the street for 2 years. (with deuce axles).

Jim

 

[eldgenb]

Ok. Here they are. Donor truck was a 1952 M51 for most of the parts.

that is a very cool truck!! too bad its not a chevy!

 

[eldgenb]

if you get a chance you should do a thread with a breakdown of that truck, that really is a cool project.. I like weird stuff like that. One of a kind for sure.