Quad Steering

[KaiserM109]

just don't get personal.

I bought an M109 deuce about 6 years ago with the idea of making a backwoods camper out of it. Many things have transpired to keep that from happening, primarily the fact that a non-turbo multi-fuel deuce can hardly pull its own hat off at high altitude, much less haul all my junk around and pull a trailer. I also bought an MKT-85.

I bought an M923A1 almost 4 years ago sight-unseen and drove it home (long, unrelated story). I had no Idea it was so big until the day I stood next to it in the Ft. Benning GL yard, but I overcame several obstacles, including a trashed transmission, and it is now sitting, functional, in a storage yard north of Denver.

Enough history. I am planning to put the M109’s box on the back, relocate the spare to snug the box up to the cab and get its center over the intermediate axle and relocate the exhaust all the way to the back.

Because it has a TERRIBLE turning radius I have 2 things in mind for it:
1. Bob it.
2. Give it Quad Steering.

There are some switch backs that the truck currently could not handle, particularly towing a trailer. General Motors offered Quad Steering on Suburbans and pickups for a while around 2005, so it’s at least somewhat practical. Monster trucks also implement Quad Steering. It would be for use no faster than 10 MPH, so the controls don’t need to be really precise. I would need some sort of controls, probably hydraulic.

I have studied the front axle on my M923 and have identified a few problems.
1. Hydraulic controls implies a hydraulic pump. I don’t think it would be a good idea to try to run both steering boxes from the original pump.

2. Brakes!! The back brakes have 2 actuators on each wheel with an emergency spring. The front has only one actuator w/o the emergency spring.

3. The ABS sensor is on the left intermediate wheel.

I don’t have a solution for the need of more hydraulic volume. For the brake and ABS problem, I think the best solution might be to somehow mount the backing plates from one of the throw-away rear axles on the new, formerly front axle.

Has anyone else thought about this or maybe even tried it?

 

[adamsoffroadperformance]

I've dealt with a fair amount of rear steer setups in monster trucks and offroad trucks. the steering part is easy I can easily help ya with that. But due to clearance when the knuckle turns and the canisters hitting stuff that's gonna be the tricky part. now it may be possible to use on of the maxi canisters from the rear axle and screw it in place of the one on the front axle backing plate to keep it out of the way. the abs can probly be retro fitted into the front brakes also with some ingenuity.

 

[adamsoffroadperformance]

For highway use it would be easy to make a pin to lock it out or even use an air cylinder to engage and disengage the lock out pin.

 

[Csm Davis]

just don't get personal.

I bought an M109 deuce about 6 years ago with the idea of making a backwoods camper out of it. Many things have transpired to keep that from happening, primarily the fact that a non-turbo multi-fuel deuce can hardly pull its own hat off at high altitude, much less haul all my junk around and pull a trailer. I also bought an MKT-85.

I bought an M923A1 almost 4 years ago sight-unseen and drove it home (long, unrelated story). I had no Idea it was so big until the day I stood next to it in the Ft. Benning GL yard, but I overcame several obstacles, including a trashed transmission, and it is now sitting, functional, in a storage yard north of Denver.

Enough history. I am planning to put the M109’s box on the back, relocate the spare to snug the box up to the cab and get its center over the intermediate axle and relocate the exhaust all the way to the back.

Because it has a TERRIBLE turning radius I have 2 things in mind for it:
1. Bob it.
2. Give it Quad Steering.

There are some switch backs that the truck currently could not handle, particularly towing a trailer. General Motors offered Quad Steering on Suburbans and pickups for a while around 2005, so it’s at least somewhat practical. Monster trucks also implement Quad Steering. It would be for use no faster than 10 MPH, so the controls don’t need to be really precise. I would need some sort of controls, probably hydraulic.

I have studied the front axle on my M923 and have identified a few problems.
1. Hydraulic controls implies a hydraulic pump. I don’t think it would be a good idea to try to run both steering boxes from the original pump.

2. Brakes!! The back brakes have 2 actuators on each wheel with an emergency spring. The front has only one actuator w/o the emergency spring.

3. The ABS sensor is on the left intermediate wheel.

I don’t have a solution for the need of more hydraulic volume. For the brake and ABS problem, I think the best solution might be to somehow mount the backing plates from one of the throw-away rear axles on the new, formerly front axle.

Has anyone else thought about this or maybe even tried it?

Okay first off to do this with a M923 I would say wrong truck, M931 is what I would have recommended to start with but you own it so let's go from there. Removing spare rack and exaust great but where are you going to mount a 425 lbs spare? Exaust underneath is easy and no brainer. Putting 109 box way forward good but look at frame flex and cab clearance closely because you plan on doing some offroading. This is also going to leave you with about 4 foot of extra frame hanging out in the rear, cut it off or make a porch? Now to the rear axle bob air ride and rear steering. Just bobbing it will help with the turning radius not sure if you need the rear steering but what we want and need are not the same most of the time. I think that I would put the rear axle at a rear most point to help with the ride and I would make an air ride suspension. Then figure out the rear steering. The power steering pump on the truck should be fine. The rear steering will not be used much and the stock front steering rams might can be used to simplify parts. You would just need the valves to make it go the direction you want. The brakes are going to be a pain.

 

[KaiserM109]

Good info, guys. Thanks.

Adamsoffroadperformance, I will keep what you suggested in mind, including your offer to help. Your experience can probably be very useful.

I plan to put the new axle in the same place as the intermediate is now because that will balance the box the same way it is on the deuce and I won’t have to mess with a custom driveshaft. Also, I want a shorter overall wheelbase to improve turning.

About the 425 lb. spare, when I had a blowout I used a come-along to get the tire up and down from the rack. It certainly needs some forethought before just sticking it somewhere. I do plan to whack off the frame so that it ends behind the box the same as the deuce. I would also give it the same clearance in front as it has on the deuce now. We would like to have a back porch, but only when stopped. What we have discussed is having a deck, possibly perforated, that folds up against the back for travel and mounting the spare on it. It will definitely take some kind of winch to lift it, at the very least a boat winch.

 

[adamsoffroadperformance]

I have some spare brake parts and stuff here if I get time I'll see if the maxi cans can be used on the front axle. steering actuation can be done several ways be it mechanical controls or electronic.

 

[73m819]

The HET m1070 has number 4 axle steer, it will take a corner then my pick up, it takes some getting used to, very easy to over steer.

 

[grendel]

I've been thinking about a bob job with 4 wheel steer... I have an extra front kicking around. Hydro would not be that hard, since there are PTO's available for the transmission or the transfer case. Most rock crawlers use bigger power steering pumps to run hydro boost brakes, rear steering, front steering etc. So not hard to get enough PSI to drive two cylinders.

 

[Csm Davis]

Hey there's a solution to a lot of the problems leave all axles but change just the rear most axle to a steering axle that will leave the ABS and spring brakes on the intermediate axle and increase the turning radius.

 

[KaiserM109]

I've been thinking about a bob job with 4 wheel steer... I have an extra front kicking around. Hydro would not be that hard, since there are PTO's available for the transmission or the transfer case. Most rock crawlers use bigger power steering pumps to run hydro boost brakes, rear steering, front steering etc. So not hard to get enough PSI to drive two cylinders.

The make-it-or-break-it for me is getting as much braking as possible and having emergency stop springs. Am I remembering wrong? Doesn't each back wheel have two brake actuators while the front only has one per wheel? My truck's 20 miles away in storage so I can't just go out and look at it.

Between us all, we ought to be able to figure this thing out!

 

[adamsoffroadperformance]

yes rears have 2 actuators. And fronts have one. not sure how much difference there would be on actual braking power I'm there is a difference just not sure how much. and the comment of leaving both rears won't work because on tandems the springs are outboard the frame and the steer axle couldn't turn or it would hit the springs.

 

[Csm Davis]

The make-it-or-break-it for me is getting as much braking as possible and having emergency stop springs. Am I remembering wrong? Doesn't each back wheel have two brake actuators while the front only has one per wheel? My truck's 20 miles away in storage so I can't just go out and look at it.

Between us all, we ought to be able to figure this thing out!

Yes the rears have two per wheel and a spring brake can, but you need to remember these trucks are setup to stop way more weight than you will ever have in your camper. Three axles but just changing the rear to steering would give you more than enough stopping power and keep the ABS, and spring brakes active and three axles give you more traction for going or slowing, 6x6! Yeah Adam you would have to change the rear suspension probably copy the rear setup on HET or PLS.

 

[KaiserM109]

I don't see how leaving the intermediate axle on and changing the rear one would work. The two back axles would be close together and trying to go different direction.

Glenn at Salina, KS has made me an offer on a whole front end, but I have only been working 2 weeks after 7 months off, so my hobby bucket is empty. What I've been planning to do is to buy the gear from Glenn, pull off the rear axles and mount the front springs. Then take a look at putting the back axle brake backing plates on the 'new' front axle. I'll have the 'new' front axle and my rear axle side-by-side. If it looks good, I'll put the 'new' front axle under the truck. Otherwise, I'll remount the intermediate axle on the 'new' springs, get it all set up as a bobber and take my time playing further with the idea of how to do the brakes on the 'new' front axle.

Adequate brakes is an absolute requirement. I can't see going from 8 actuators in the back to 2. Going to 4 with emergency springs is probably ok because I won't be hefting as much a load. Using a back axle backing plate also solves the problem of how to mount the ABS.

Tell me more about running hydraulics off of the PTO, please.