Superliner RW700 Steering axle

[1961H67]

I have a 1988 RW700 Superliner, the front axle is worn out, unfortunately it will take more than a set of kingpins to repair it, I also would love to find a axle with hub pilot hubs. Any suggestions on a later axle? CL 700 maybe? I haven’t done any research yet. 

[mrsmackpaul]

It can't be worn the 80's was only like yesterday wasn't it ????

Oh hang on, were did the years go, I swear I only blinked and "POOF" it was a whole new century  

Probably get a Rockwell or some modern front axle is the easiest  way 

 

Paul

[mowerman]

yeah someone on here just put a school bus front end under a B model....i had not thought of that,,,another completely differant vehicle,,,great idea,,,if you have got decent truck wreckers around good luck...bob

[1961H67]

Yeah I figured there will be a lot of measuring going on, I was hoping someone had already been down this road. 

[Mark T]

CL and Superliner 2 shared some frame components. Steer axle ?? It's seem like if the center bolt holes are the same, the only thing would be making sure the levers for the tie rod were the same ( if you were going to use them ) as changing those could mess up the ackerman angles.

[mrsmackpaul]

21 minutes ago, Mark T said:

the only thing would be making sure the levers for the tie rod were the same ( if you were going to use them ) as changing those could mess up the ackerman angles.

Correct, so the wheel base needs to be similar as the wheel base is what the ackerman is set to 

 

Most common axles have interchangeable rods to allow for different wheel bases

 

Paul

[1961H67]

I’m going to give it a pressure washing and get some measurements, I think I know where a CL 700 dump truck is , the frames look the same but I have never measured spring centers . 

[1961H67]

I have been pressure washing in my spare time, I took the Herd guard off today, so I could really get some good measurements, I’ll post a picture of the axle number if anyone can tell me what rating it is. Also center bolt to center bolt is 34.5 with a 4 inch wide spring, from what I can find a RW & MH is the only axle that is the same, Unless some CLs had a 4 in spring, It has converted hub pilot hubs on it now that I could use if I can find a axle with the same rating ( it came new with twin steering boxes and the right one was removed by the previous owner. ) it’s  a pretty decent old Superliner, 3406B , 18 speed Eaton, Newer Mack air ride rears 3.90 ratio. I’m planning on restoring it when I get the shop repaired and using it , but the steering axle the first project. 

[harrybarbon]

Twin steering boxes, I have never seen or heard this. How common are twin steering boxes?

[mrsmackpaul]

It was a Yanky thing in Seppo land only as far as I know 

I have no idea why, and will never understand a lot of this over complicated stuff

 

Paul

[Mark T]

There is a way they can be sleeved . I've seen it work on 12s usually a big 20 that actually sees 20000 on it, the repair doesn't last long. But then again, used to see more places willing to do such repairs.

[Mark T]

1 minute ago, mrsmackpaul said:

It was a Yanky thing in Seppo land only as far as I know 

I have no idea why, and will never understand a lot of this over complicated stuff

 

Paul

Twin steering boxes, refers to  a steering box on the right side. ( where you guys normally have them )  Bigger axles here often have another box, or some form of hydraulic cylinder on the right side to help turn the wheels when steering. 

[mrsmackpaul]

Is that another box on the RHS ?

[Mark T]

44 minutes ago, mrsmackpaul said:

Is that another box on the RHS ?

Yes. It had no input other than the hydraulic lines going to it. Macks most often used a right side box on heavier steers. Other makes might have used an assist cylinder on the right. The right side assist box wasn't exclusively Mack either.  Fairly common here on steer axles rated higher than @ 12000 pounds.  

[1961H67]

Yes a lot of stretched out dumps came with dual boxes, we have a KW dump with twins on it , Lots of CL 700s do . It just takes the pressure off the tie rod , more if it were off road in soft ground , I would not put one back on the right side for what I’m going to use it for. And I spoke to an axle guy that can repair it but I’m not in a big hurry so I had rather just replace it with a good used one. 

[The Heinz]

8 hours ago, harrybarbon said:

Twin steering boxes, I have never seen or heard this. How common are twin steering boxes?

Pretty common here in NC, especially on heavy dumps and cement mixers. ST Wooten has a lot of mixers using that design, I'm staring at one now. 

[1961H67]

Heinz , is there any way I can come up with an axle number like I need with the vin of my Superliner? Even though I would love to find a fit with hub pilot hubs and mine had stud pilot thank you 

[The Heinz]

It will tell me a part number, but that's about it. I could try cross references and such, but that's nothing set in stone. 

[mrsmackpaul]

So from what I'm reading here, I'm thinking the second steering box was for making it easier on the mechanical side of the steering for tight maneuvering by working on two tie rods instead of just one 

For trucks running around in town, backing into tight spots and so on, not for line haul interstate trucks 

Fairly smart idea if I have that correct

 

Paul

[Geoff Weeks]

Yes, the tie-rod just keeps the tires in "sync" with eachother and the forces are supplied by the dual boxes.

Sheppard made a "box" that looks identical to the "392" but it has no input shaft, the oil is controlled and supplied by the master box (Left in the US).

Some others have used a double acting hyd cylinder, much cheaper, but when pressure is on the rod side of the cyl the forces will not be equal like they are with the whole slave gear. (Rod side has less area than the non-rod side).

Edited 8 hours ago by Geoff Weeks

[Geoff Weeks]

Paul, the dual gear starts on pg 62

https://www.rhsheppard.com/wp-content/uploads/2019/02/92-Series-Sheppard-Power-Steering-Service-Manual.pdf

[1961H67]

Great explanation Geoff ! 

[Mark T]

19 hours ago, 1961H67 said:

I have been pressure washing in my spare time, I took the Herd guard off today, so I could really get some good measurements, I’ll post a picture of the axle number if anyone can tell me what rating it is. Also center bolt to center bolt is 34.5 with a 4 inch wide spring, from what I can find a RW & MH is the only axle that is the same, Unless some CLs had a 4 in spring, It has converted hub pilot hubs on it now that I could use if I can find a axle with the same rating ( it came new with twin steering boxes and the right one was removed by the previous owner. ) it’s  a pretty decent old Superliner, 3406B , 18 speed Eaton, Newer Mack air ride rears 3.90 ratio. I’m planning on restoring it when I get the shop repaired and using it , but the steering axle the first project. 

That truck looks to be in nice shape. 

[Mark T]

2 hours ago, mrsmackpaul said:

So from what I'm reading here, I'm thinking the second steering box was for making it easier on the mechanical side of the steering for tight maneuvering by working on two tie rods instead of just one 

For trucks running around in town, backing into tight spots and so on, not for line haul interstate trucks 

Fairly smart idea if I have that correct

 

Paul

They're popular here on trucks with bigger steering axles (higher weight ratings)  A little odd, not all the Macks had that set up. Older R models, CVs , wasn't uncommon to see those with nothing on the right.  I had 2 '07 Granites one was a CTP713 and one was a CTP713B. The "B" (axle back) had the box on the right and the axle forword one had nothing on the right. It did have what seemed to be a more beefier tie rod and ends.  Then there were other models that had a box on the right and the steer axle was only like a 14 or 16 thousand pound rating. Some of the other manufacturers that used two boxes also incorporated some form of cooler into the system as well.  I'm as surprised as you are reading this that those trucks you guys use don't have some form of assist on the left. 

[mrsmackpaul]

I have never been to the State's so dunno bugger all about driving there

I wonder if it was more common on the east coast than the west coast of the State's ?

I wonder are the roads a lot windier (dunno if that's the right spelling or not) than Australia 

Even on our really rough work there is, as far as I know, just one steering box

I was surprised going to New Zealand just how narrow and winding their roads are compared to Australia, lot's more hills than Australia 

So I'm thinking it has a lot to do with the operating environment 

 

Paul