My steering box was leaking from the steering sector or the shaft that the Pittman arm slides onto. There is a seal at both ends of this shaft and both had failed. You can access both of these seals (actually two seals and a "O" ring) without pulling the box. From inside the compartment under the drivers' seat remove the end plate by bulling the 6 or so bolts. In this cover is a seal and a "o" ring around the end plate. You must remove the Pittman arm. I pulled the generator forward and slid under the generator to access the square whole that was in front of the gen radiator. Through this hole I pulled the Pittman bolt with a 5/8 Allen 1/2 drive socket. Then pulled the arm with a three jawed puller. After pulling the arm, the sector pulls out the previously pulled end plate area. You'll see the deteriorated seal when the sector shaft is removed. I used a curved pick and a small flat screw driver to scrape out the old seal. The new seals go in with the black toward the inside and the white toward the outside. Called the box manufacturer and was told these seals are failing prematurely. The other seals in this unit are holding up well. I'd been told $400 to $500 for R and R plus $650 for rebuilt unit. My coach has maybe 60k miles but is 15 years old.
Not knowing any better, I did pull the complete box. That thing must have weighed 100 lbs.!!!
Wanted to post this because I couldn't find anything on line including here about the foretravel version of this box.....Need to say the "BEAM" site has the factory info but this unit is not described anywhere............
Dennis Davis
The steering Box is A Shepard model 100, Rebuilding them is not rocket science getting them out is a whole other issue. I just went down the replacement road because of time constraints, I had mine replaced with a Shepard factory rebuilt unit, it lasted about 200 miles, we are on the second one now it's made it about 150 miles so far. Couple of things make sure your sealing surfaces are not pitted or grooved up, and be sure to set you steering stops on the gear box to between an 1/8 and 1/4 inch away from the axle stops or it will blow the input shaft seal out. A little tip I cut a hole in the generator box next to the steering gear for way better access, then just screwed a cover over the hole
There are some other folks here that have some contacts for steering gear rebuilders that seem to be much better than the factory and less expensive, perhaps they will chime in.
I bought the seal kit at the local Mack dealer for under 30 bucks watched a video I think on the Shepard web site. Took about 3 hours. I found my seal was installed upside down. It is easy make sure to put the seals in right.
Alan :)
I paid FOT to replace the steering gear with a unit rebuilt at Sheppard after the seal on the Pitman arm side failed. Two years later, the top seal blew out and the unit lost about 3 1/2 gallons of oil in about five miles of driving. A customer service representative reported that such a failure is caused by the pressure relief plungers not being set properly. My wife and I set the relief plungers in the driveway at home after an RV dealer replaced the top seal, but refused to set the plungers.
I had two friends who had leaky top seals. One was successfully fixed in less than three hours. The other was fixed and blew out the next day because the mechanic did not do the job properly. The top seal is relatively easy to replace.
Seals are available at Kenworth dealers. They are probably available at other truck dealers as well. Sheppard has excellent videos and literature regarding operation and adjustment of their steering gears. Service (http://www.rhsheppard.com/service.htm)
If the steering gear required removal (and usually does for repair on the Pitman arm side), I would send the unit to Red-Head Steering Gears - Custom Rebuilt Steering Gear Boxes in USA (http://www.redheadsteeringgears.com) to be rebuilt. That would require a few days, but not necessarily longer than the wait for any complete rebuild. Brett Wolfe has recommended Red Head.
Dennis, Do you have part numbers for the seals?
Mark
I used RED HEAD this summer to build and blueprint my box. They charged about $500 and that included shipping back to me from Washington State to Chicago. 24hr turn around.
GREAT people to talk to.
The box does weigh a 100pounds, I dropped it on my foot after it slipped out of my hands (oil) pulling it out through the fan bay, OWWWWWWWWWWWCH!
I bought the complete kit from FOT here in Nacogdoches. It cost around $100. I may be able to get just the number for the sector shaft seal kit and I'll send it to you.
Dennis
http://www.rhsheppard.com/service/Seal_Kit_Part_Numbers.pdf (http://www.rhsheppard.com/service/Seal_Kit_Part_Numbers.pdf)
Wish I had known all this before installing a factory rebuilt unit that cost a whole lot of $$$ and has a little more play than the old unit. Didn't think it would be possible to replace the seal without pulling the box. Live and learn.
I had a Shepard re-built steering box installed in 2010. It hasn't given me a moment's problem. It I have a seal failure in a part after a dozen year's of service, I believe it makes good sense to re-build the unit rather than fix just today's problem.
Thanks JD