anyone have a good write-up on hydro steering

[73redblaze]

the title sums it up. oh and do you need crossover for hydro? i dont think so but i just wana know.

 

[Hogback Fabrication]

You mean hydro assist and a search will get you the info you need.

And yes, you need crossover unless you feel like ripping your steering box off of the frame.

 

[dremu]

Yeah, I'm trying to visualize the 2" throw ram to hydraulically assist the stock push-pull draglink

Anyway, crossover is the first step -- it'll considerably improve steering issues, especially with lift. After that if you still have issues you can talk about hydro assist.

-- A

 

[twoslo4five0]

Yeah, I'm trying to visualize the 2" throw ram to hydraulically assist the stock push-pull draglink

Anyway, crossover is the first step -- it'll considerably improve steering issues, especially with lift. After that if you still have issues you can talk about hydro assist.

-- A

actually i know some guys running it with no problems...would i??no but its been done

 

[77scottsdale]

my new project has ram assist on the stock z link guy who had before me drove it on the road for a while and then went to river rock in milledgeville Georgia, and bent the tierod but it steers fine, could you elaborate why the steering box will be yanked off, cause i wont to fix mine before it falls off, and why does it matter if you have crossover or z link the ram is only on the tierod and it is assisting so if you aint turning the wheel the ram aint working, i could see it happening if the ram was working against you.

 

[dremu]

Oh yea... I was thinking the ram mounted to the draglink.

Now, with push-pull I could see the ram bending the tierod or busting the knuckle, 'cuz the draglink would be resistant to the force coming back from the ram ... but I also fear bumpsteer with hydroassist =))

-- A

 

[77scottsdale]

does the stock setup even have a drag link i wouldn't qualify this as a drag link but i guess it is a small one this is a 2" drop

and how in the hell would you mount the ram to the drag link
and one more thing the ram is not going to come back on its on the steering wheel has to be turned unless you rig up some kind of return to center, the steering wheel is the switch for the ram

 

[77scottsdale]

here is a pic of mine with a bent tierod not draglink i have a wfo concepts 1.5" dom tierod on the way so i wont have any more tierods bent but may be some bent tierod ends

 

[Jason4x4]

The sep '08 petersons has a writeup on putting ram assist on a 86 army truck with stock push pull steering.

 

[Hogback Fabrication]

my new project has ram assist on the stock z link guy who had before me drove it on the road for a while and then went to river rock in milledgeville Georgia, and bent the tierod but it steers fine, could you elaborate why the steering box will be yanked off, cause i wont to fix mine before it falls off, and why does it matter if you have crossover or z link the ram is only on the tierod and it is assisting so if you aint turning the wheel the ram aint working, i could see it happening if the ram was working against you.

With steering that is mounted between the frame and axle (mechanical steering, stock or crossover) the horizontal length of the draglink changes throughout the suspension travel. The longer the draglink, the less apparent these changes are. A longer draglink will tend to retain the static steering control, you will actually be able to steer left and right like you could on flat pavement with a long draglink (i.e. crossover).

A short draglink will have drastic changes in horizontal length during suspension travel and you won't have much steering control (when the driver side droops you won't be able to turn left and vice versa).




Now, onto how this relates to hydro assist steering:

Mechanical and hydraulic steering, at least as we generally see and use them, inherently clash.

The hydraulic part of hydro assist steering (mounted on the axle and moving components that are also on the axle) couldn't care less what the suspension does. Hydraulic pressure is applied based on the position of the valve in the steering box, which is directly related to how you are turning the steering wheel. When you turn the steering wheel left, the ram applies pressure to turn the axle left regardless of anything else.

The mechanical part of hydro assist steering, the draglink, is heavily influenced by suspension travel. When one side of the axle compresses or droops, the horizontal length of the draglink changes. The reason that all of us swap to crossover steering is to increase the draglink length and hence decrease the influence that suspension travel has on steering control. When you turn the steering wheel left, the mechanical part steers the axle based on the droop/compression the axle is currently experiencing, which varies greatly.


Basically, the mechanical steering is drastically affected by suspension travel while the hydraulic assist is not affected at all by suspension travel which caused things to bind.




Now, imagine a setup with the stock draglink with hydro assist. The driver side tire is at full droop, steering wheel is at full lock left. Because of the crappy stock steering, the tire is still pointed straight forward. The short draglink isn't capable of steering the truck like you want it to.

At the same time, the hydraulic ram is receiving pressure from the pump because the steering wheel has been turned left. Even thought the mechanical linkage can't turn left, the hydraulic part of the steering is forcing the steering and things bind. No question, something breaks in this situation and the frame is probably the weak link.


In theory, even crossover should bind when used in tandem with hydraulic assist but experience (myself included) proves otherwise. My guess is that there is enough play in the GM steering boxes that the steering doesn't bind with the long draglink that crossover steering uses.

 

[BGKYK5]

This is the best write up I know of on hydro assist.

http://coloradok5.com/forums/showthread.php?t=159921

Edit: There are better ways to tap the box now, namely in the front and top.

 

[mnstrburbon]

my friend is also running assist with z for going on 8 months no issues so far.