Power steering options for solid axle trucks

[octanejunkie]

Looking at power steering options for my Task Force truck I found the NoLimit Power Rack for Straight Axle kit through this forum.

I've seen the website, I called the company, I spoke with a fellow there and read the instructions... ok, but how does it feel to drive with it? I'd really like to hear from people that have this kit on their trucks, or had this, on their truck.

Please share your experiences, I'm very interested in this product but NoLimit isn't shipping for a few weeks (waiting on a shipment of brackets) so I'm using my wait time wisely and asking around before rushing to buy it.

I am currently running a Toyota p/s box-kit from CPP in the stock location, and it's OK, but it uses the same steering design and geometry as the factory and I'm interested in upgrading and improving it as much before going IFS.

Appreciate any thoughts, experiences or comments. Thanks

[1project2many]

I am currently running a Toyota p/s box-kit from CPP in the stock location, and it's OK, but it uses the same steering design and geometry as the factory and I'm interested in upgrading and improving it as much before going IFS.

The primary weakness in the OE system is insufficient rigidity. The truck is designed to use skinny bias ply tires with stiff sidewalls. Introducing soft wide radials increases the tire's resistance to turning. Applying more force to the steering gear causes parts to bend and flex. On the flip side, if the road applies force that tries to turn the tire, and you hold the wheel still, the steering gear will flex and allow some steering at the tire. If you can strengthen the steering gear you can improve the road feel and response.

Related: At what weight / GVW do the steering arm and tie rod diameter change? They are substantially larger on two ton trucks, but are they larger on one tons? 3/4 tons?

[octanejunkie]

Originally Posted by 1project2many

The primary weakness in the OE system is insufficient rigidity. The truck is designed to use skinny bias ply tires with stiff sidewalls. Introducing soft wide radials increases the tire's resistance to turning. Applying more force to the steering gear causes parts to bend and flex. On the flip side, if the road applies force that tries to turn the tire, and you hold the wheel still, the steering gear will flex and allow some steering at the tire. If you can strengthen the steering gear you can improve the road feel and response.

Related: At what weight / GVW do the steering arm and tie rod diameter change? They are substantially larger on two ton trucks, but are they larger on one tons? 3/4 tons?

All of my steering components are upgraded except the steering arm on the spindle. I have a 1" tie rod and new ball joints. I have a beefier, adjustable drag link and a custom pitman arm that is the same length as the stock pitman arm. My steering geometry is exactly the same as OE.

My steering box is mounted to a bracket that is maybe 5.8" thick and bolts to the top bottom and side of the frame - though I'm sure the frame can probably twist and flex and I'm sure my 31" LT tires aren't helping the situation any...

I recently added a steering damper between the tie rod and axle which helps take some of the road-induced feedback and bump-steer related action (wander, tire grabbing, etc) out of the equation, but also softens the feeling of the road.

In addition to a quicker ratio steering, it would be nice to have a steering gear that does not have any inherent free-play as these trucks do like to wander a bit - even with only 1/8" toe in - which is why I'm looking at R&P.

[1project2many]

I dunno if I'm thinking of this more technically. But free play is usually caused by looseness in the joints or connections. If the tie rod is worn out, or if the drag link has worn ends you'll have free play. The steering gear can have no free play and still be subject to unwanted steering input from the road. That's the problem with our gear. You've already removed some of the issues but I'll bet you'll be surprised to know the steering arm is actually fairly flexible. You can usually see this by having a helper turn the wheel back and forth and watching the drag link move while the tie rod does not. The steering arm curls and uncurls as the drag link moves. And after the steering arm comes the lower portion attached to the tie rod. On the vintage racers we'd build braces or weld in plates for added strength. On a street vehicle it's not recommended to weld to steering gear which is why I asked about different GVW trucks.

I set my caster more positive for better highway feel. It causes the wheels to resist steering input while driving. Maybe yours is already set that way.

I think r&p sounds like a good move. If you want to continue to improve the steering gear, the components I listed are the ones I've found need to be changed or modified. To truly make the original design gear respond and feel like a modern vehicle I believe you will need to address nearly every part of it.

[octanejunkie]

The ToyotaFSM states up to 40mm free play is allowable, and common, according to the guys on the Toyota forums.

Im running with 2 degrees of positive caster now, and about to go to 6 degrees. How much caster are you running?

I am interested in improving the handling of the vehicle as much as I can. I realize there is inherent flex in the OE design and parts but I'd really like to hear some real world feedback about a power R&P on these trucks before I spend another $800 chasing a dream when only $3,500 more makes it a reality (read IFS)

[1project2many]

40mm of free play? What you're talking about is steering wheel free rotation. 40mm is approximately 1.5" of wheel rotation. That much travel is max allowed not minimum obtainable. It is a total measurement for all play and motion allowed in the entire steering gear. It is not a measurement of how much play is allowed in the box and it is certainly not a "preferred" value.

Steering wheel free travel is not exclusive to solid axle suspensions. Nor is it excluded from rack and pinion systems. I can think of plenty of trucks and vans I've driven over the years that have 1.5" of wheel play but don't feel too loose on the road. We have a 2003 Sprinter here that has about 3/4" of an inch of travel before effective steering begins. That's an IFS, rack equipped front end.

With a traditional steering gear the easiest way to reduce that travel, when the gear is in good mechanical condition, is to install a steering box with a faster ratio. But I do not know if that's an option with the Toyota boxes.

I am currently running a Toyota p/s box-kit from CPP in the stock location, and it's OK, but it uses the same steering design and geometry as the factory and I'm interested in upgrading and improving it as much before going IFS.

I am interested in improving the handling of the vehicle as much as I can. I realize there is inherent flex in the OE design and parts but I'd really like to hear some real world feedback about a power R&P on these trucks before I spend another $800 chasing a dream when only $3,500 more makes it a reality (read IFS)

These two quotes say different things. The first says you're interested in improving the Toyota steering setup. The second clearly says you're looking for feedback on a specific aftermarket rack kit. I hope you can see why I provided the answers I did.

I believe I set caster at 4.5 degrees. I am using 225/75 16 tires which may have a smaller contact patch than your tires. I can dig out the alignment specs if you're curious about other dimensions.

Good luck. If you decide to install the rack kit, please share the results.

[Softpatch]

I subscribe to this thread good info right here.....Sp

[octanejunkie]

Originally Posted by 1project2many

40mm of free play? What you're talking about is steering wheel free rotation. 40mm is approximately 1.5" of wheel rotation. That much travel is max allowed not minimum obtainable. It is a total measurement for all play and motion allowed in the entire steering gear. It is not a measurement of how much play is allowed in the box and it is certainly not a "preferred" value.

Steering wheel free travel is not exclusive to solid axle suspensions. Nor is it excluded from rack and pinion systems. I can think of plenty of trucks and vans I've driven over the years that have 1.5" of wheel play but don't feel too loose on the road. We have a 2003 Sprinter here that has about 3/4" of an inch of travel before effective steering begins. That's an IFS, rack equipped front end.

Understood and appreciated. All commercial steering systems have some free play. I would like to reduce this in my system as much as possible, regardless of what steering gear I use.

Originally Posted by 1project2many

With a traditional steering gear the easiest way to reduce that travel, when the gear is in good mechanical condition, is to install a steering box with a faster ratio. But I do not know if that's an option with the Toyota boxes.

This is not an option I have found with Toyota boxes of the same size/housing.

Originally Posted by 1project2many

These two quotes say different things. The first says you're interested in improving the Toyota steering setup. The second clearly says you're looking for feedback on a specific aftermarket rack kit. I hope you can see why I provided the answers I did.

Sort of. If I can get reasonably responsive steering out of the OE design with my current Toyota setup and OE axle then I'd be happy. If I cannot, I am willing to consider a bolt on R&P if it gets me a quicker ratio AND has inherently less free-play in the rack. If I cannot, then I am willing to look at an IFS system; which unfortunately comes at a much higher cost.

Originally Posted by 1project2many

I believe I set caster at 4.5 degrees. I am using 225/75 16 tires which may have a smaller contact patch than your tires. I can dig out the alignment specs if you're curious about other dimensions.

I am running 31.5x10.5-R15 tires. I have 1/4" toe in, 2° positive caster and stock camber provided by the axle/spindle/kingpin. I have a set of 6° shims I am ready to try with the understanding this will further affect the steering and wheel return. While many folks believe that "as much positive caster as possible" is the way to go, I understand that everything is a trade off. Playing with caster is inexpensive and easy on these trucks, so it's worth trying.

Originally Posted by 1project2many

Good luck. If you decide to install the rack kit, please share the results.

Thanks for all your input, I appreciate your perspective and experience. I think this is a good topic overall, and a very subjective one when it comes to how something "feels" - which is why getting first-hand feedback from someone with this vs. that is really just an opinion, not law. I know that the power rack kit does not affect caster, camber, toe, etc by itself, and that each of these affect the experience as well. But the R&P does remove the steering knuckle, drag link, tie rod, etc and that is a significant change to some of the OE flex inherent in the design.

[1project2many]

Dodge worked hard to devise a solid axle front suspension and steering linkage that was comfortable and usable by modern standards. They did well enough that Mercedes' engineers didn't make any major changes unless a vehicle was switched to IFS.

Look at the Grand Cherokees up to '04, the full size trucks, and even the Wranglers for an idea of what improves ride and handling. The steering knuckles and components are really quite beefy compared to our trucks.



In my experience using solid axles to build vintage race cars the steering arm at the drag link is a bad flex point. The tie rod "ears" are better but still prone to flex. We run soft tires that are 12" - 14" wide on the race cars but the cars themselves are lighter than the truck. Installing a rack or changing steering so the arm is not part of the equation makes a noticeable improvement in steering response and improves control. It does not change the ride.

[octanejunkie]

Interesting background on the Dodge route, I will have to take a look at that on my next trip to the junkyards. the addition of Idler arms and steering linkages vs. direct connections makes a big difference, as does beefing up all the components. It's clear that the early trucks were under-designed in several areas by today's standards.

Originally Posted by 1project2many

Installing a rack or changing steering so the arm is not part of the equation makes a noticeable improvement in steering response and improves control. It does not change the ride.

This is my goal, improving response and control. If that takes me to a power R&P, so be it, but for the time being I'm still enjoying the ride in my high performance tractor of a truck

[bomber66]

I have the No limit R&P on my 55 TK, put a thousand miles on it last year. Everything new in front end with Poser 3 inch drop springs, started out at 2 degree shims, buy ended up with 4 degrees. Was wanting to dart around at speed with only 2 degrees, 4 degrees fixed it.

It does away with the wimpy stock tierod and ends. Steers great with very little bumpsteer, and tracks good on the street and interstate. The only thing I don't like about it is that the rack is bolted directly to the axle and it moves up and down with a slipjoint in the steering rod, you need to keep that joint greased well to cushion vibrations that transmit up the rod. Basically if you hit bumps, you will feel it in the steering wheel. Not bad at all though...

Overall, I'm very pleased with the kit, does exactly what I wanted it to do and was very easy to install.

[47AD]

I was looking around the internet and came across this site and this has my curiosity up a little. I intend to contact this company to see if they actually have this cross steer kit in the works. If they do, it might be another good option.

http://www.butchscoolstuff.com/blog/...steering-info/

Dan

[octanejunkie]

Originally Posted by bomber66

I have the No limit R&P on my 55 TK, put a thousand miles on it last year. Everything new in front end with Poser 3 inch drop springs, started out at 2 degree shims, buy ended up with 4 degrees. Was wanting to dart around at speed with only 2 degrees, 4 degrees fixed it.

It does away with the wimpy stock tierod and ends. Steers great with very little bumpsteer, and tracks good on the street and interstate. The only thing I don't like about it is that the rack is bolted directly to the axle and it moves up and down with a slipjoint in the steering rod, you need to keep that joint greased well to cushion vibrations that transmit up the rod. Basically if you hit bumps, you will feel it in the steering wheel. Not bad at all though...

Overall, I'm very pleased with the kit, does exactly what I wanted it to do and was very easy to install.

Thanks for your input. The instructions do make it look pretty easy to install. I have a few questions, if you don't mind:

What is the ratio of the rack? (how many turns lock to lock)

How much space is there between the rack and the axle?

How much caster are you running?

How much free-play is there in the rack itself?

Which pump and what size (diameter) pulley are you running?

Thanks again!

[octanejunkie]

Originally Posted by 47AD

I was looking around the internet and came across this site and this has my curiosity up a little. I intend to contact this company to see if they actually have this cross steer kit in the works. If they do, it might be another good option.

http://www.butchscoolstuff.com/blog/...steering-info/

Dan

Hey Dan, welcome aboard!
Looked at Butch's page, wish there were pictures, but I did google the vega steering and found several pictures of the vega box and cross steering linkages

http://i601.photobucket.com/albums/t...gsystem001.jpg
http://static.speedwaymotors.com/ima...sssteering.gif

Things to think about...

[bomber66]

Here's a pic of everything installed, I believe it's a 80's Ford T-bird unit that comes with the kit. I'm using a GM PS teering pump with a pressure reducer. The Ford rack uses less pressure than the GM stuff and a reducer is a must.

[octanejunkie]

Originally Posted by bomber66

Attachment 1357370

Here's a pic of everything installed, I believe it's a 80's Ford T-bird unit that comes with the kit. I'm using a GM PS teering pump with a pressure reducer. The Ford rack uses less pressure than the GM stuff and a reducer is a must.

Thanks for the pic, and info.

Do you have a part number on the pressure reducer? No Limit didn't mention it in their docs nor when I spoke with them.

[47AD]

I emailed Butch's Cool Stuff about the cross steering kit for the 47 - 54 Chevy trucks and I got a response back fairly quick. He indicated that they are not making the kit now but is on their short list of kits that will be added sometime in the near future.

Well, I hope it's available before I get to that point on mine.

Dan

[octanejunkie]

Originally Posted by 47AD

I emailed Butch's Cool Stuff about the cross steering kit for the 47 - 54 Chevy trucks and I got a response back fairly quick. He indicated that they are not making the kit now but is on their short list of kits that will be added sometime in the near future.

Well, I hope it's available before I get to that point on mine.

Dan

Cool!

Are they using a Vega box (manual) and did they give you an indication of price and whether a power steering option would be available?

[47AD]

The initial response I got did not indicate what box, or price range so I have emailed him again to see if he can give a few more answers to these questions. I will let you know as soon as he replies.

Dan

[Rambow]

With the rack mounted directly to the straight axle like that, how does the column linkage not come apart with normal suspension travel?

Does it have some kind of slip joint or something??

[47AD]

I just received another response from Terry at Butch's Cool Stuff and he wrote that the cross steer kit would use a Saginaw 525 non power box and the kit price would be somewhere in the $625 range. It would be nice if a power box were available. At any rate, when the kit comes out it will be nice to have another option.

Dan

[1-ton of fun]

Originally Posted by Rambow

With the rack mounted directly to the straight axle like that, how does the column linkage not come apart with normal suspension travel?

Does it have some kind of slip joint or something??

it would have to have a slip joint. preferably a greaseable one.

[Clarance J]

octanejunkie. If you Google "Mustang II power steering Flow control valve" you will find the number and price. I got mine from Jegs. Good luck.
Earl

[octanejunkie]

Originally Posted by Clarance J

octanejunkie. If you Google "Mustang II power steering Flow control valve" you will find the number and price. I got mine from Jegs. Good luck.
Earl

Thanks Earl, I did just that and found several. Summit has this one with a male -6 connection, which is handy, but I also found several others with different size orifices to "tune the feeling" through the flow. Any thoughts there?

Originally Posted by 1-ton of fun

it would have to have a slip joint. preferably a greaseable one.

Up in post #11 Bomber66 mentions the slip joint, which according to the instructions supplied by No Limit, is a trim to fit part based on your suspension travel.

Originally Posted by 47AD

I just received another response from Terry at Butch's Cool Stuff and he wrote that the cross steer kit would use a Saginaw 525 non power box and the kit price would be somewhere in the $625 range. It would be nice if a power box were available. At any rate, when the kit comes out it will be nice to have another option.

Dan

Thanks for the effort, and the info, Dan!

Perhaps they'll sell a version of the kit without a steering box so we can add our own - or develop a version that puts the steering gear in the stock location...
Yes, it's good to have options