2007 M1151A1 Sheppard Steering Fluid Leak Repair

[HoveringHMMWV]

Finally started repairing my fluid leak which occurred last fall during a veteran's event. Did a lot of reading on the subject including TM's, manufacturer's documents, SS posts, and even YouTube videos. I concluded that I had a leak at the output (sector) shaft. The rest of the assembly was completely dry including the hose connections, input shaft, and rear sector shaft seal.
The weather was very nice today in central AL and I was able to open up the garage and go to work. Started by disconnecting the stabilizer bar from the L/R frame members which allowed it to lower just enough to access the spline nut on the Sheppard gear box. Lock tabs were then adjusted on the spline nut to allow loosening. A large 14mm hex head socket along with an impact driver was used to remove the nut.

 

[HoveringHMMWV]

A heavy duty pitman arm puller along with an impact wrench made quick work of loosening the pitman arm. However the pitman arm would not clear the end of the shaft while the pitman arm was still connected to the steering drag link. I then disconnected the idler arm from the right hand frame. This allowed the steering drag link to lower enough for the pitman arm to clear the end of the shaft.

 

[HoveringHMMWV]

I am now at a stopping point because I was unable to pull the sector shaft from the Sheppard gear box housing. A run to the parts store will hopefully yield me a slide hammer which should do the trick (according to the manufacturers videos).

 

[HoveringHMMWV]

Back at it again today and I found that I was unable to remove the sector shaft without pulling the Sheppard gear out of the HMMWV. I removed the input/output hoses and let the system drain. The large bolts holding the gear to the frame required an impact for removal. The left front wheel needed to be removed for that to happen. I don't like working underneath a vehicle which is on jack stands, so I opted to remove the tire, barely loosen the bolts, and then reinstall the tire. I'm also a solo operation so I needed a way to secure the gear before removing the last of the three bolts. A tactically placed ratchet strap (paying attention not to pinch/bind any hoses or lines) and using a garage support pole, worked great. Pulled the last bolt, released the strap tension, and lowered the gear onto the steering link and sway bar. Now from under the truck, a slight twist and turn of the gear allowed me to lower the gear. CAUTION: I had read and will agree that the Sheppard gear is smoking heavy. This is really a two-person operation but the ratchet strap worked great (installation will be another problem to solve).
Tomorrow I plan on tackling the sector shaft seals.

 

[HoveringHMMWV]

Today's progress came to another stop trying to figure out how to remove the dust seal without damaging it. This seal has to be removed for the sector shaft to be pressed out. After speaking to a few online friends, I came to conclusion that this dust seal is a press fit and not made to be removed without damage (or at least I don't have the tool or even know what the tool is called). I removed enough rubber around the edge of the seal to insert a screw driver and began lifting the seal out. Once removed, the snap/retaining ring which holds the shaft in place was accessible. A large set of snap ring pliers was required to remove the ring.

 

[HoveringHMMWV]

Pretty day and lots of progress! Had to use my hydraulic press to push out the sector shaft. The large diameter top end of the shaft (under the dust cover) had a bit of rust around the outer edge but the internals of the gear looked new. I cleaned up the rusty spots with a wire wheel taking care to prevent debris contamination. I did find why the leak originated in the lower shaft seal (near the pitman arm) as it had deteriorated / dry rotted somehow and pulled out in pieces. Seals were replaced, sector shaft reinstalled (using alignment marks), new snap ring installed along with a new press fit dust cap (included in kit).



Installation of the gear was a similar process to it's removal using a ratchet strap. I initially lifted the gear onto the stabilizer and steering linkage. While balanced there, I rigged up the ratchet strap to hold the gear in place just in case I lost my hold while lifting. I used two smaller diameter bolts to initially hold the gear in approximate position for fastening. Removing those smaller "alignment" bolts one by one allowed me to more easily start and then tighten the correct fasteners.



Today was finished up by installing/tightening the hoses, reattaching the steering wheel linkage, reattaching the pitman arm, and finally the idler arm. The pitman arm will be torqued down correctly after the system is filled, bled, and checked for leaks. The final tasks bill be to reattach the left splash shield, hood prop, and stabilizer bar (as this interferes with the hex socket required for pitman arm).

Thank you to those who answered my questions, gave guidance and insight. There are other Sheppard steering gear repair documents and videos out there, but the M83P2 as installed on my M1151A1 could not be found. I hope this writeup with help someone in the future.

 

[TNDRIVER]

Pretty day and lots of progress! Had to use my hydraulic press to push out the sector shaft. The large diameter top end of the shaft (under the dust cover) had a bit of rust around the outer edge but the internals of the gear looked new. I cleaned up the rusty spots with a wire wheel taking care to prevent debris contamination. I did find why the leak originated in the lower shaft seal (near the pitman arm) as it had deteriorated / dry rotted somehow and pulled out in pieces. Seals were replaced, sector shaft reinstalled (using alignment marks), new snap ring installed along with a new press fit dust cap (included in kit).

View attachment 963816 View attachment 963817

Installation of the gear was a similar process to it's removal using a ratchet strap. I initially lifted the gear onto the stabilizer and steering linkage. While balanced there, I rigged up the ratchet strap to hold the gear in place just in case I lost my hold while lifting. I used two smaller diameter bolts to initially hold the gear in approximate position for fastening. Removing those smaller "alignment" bolts one by one allowed me to more easily start and then tighten the correct fasteners.

View attachment 963819 View attachment 963821

Today was finished up by installing/tightening the hoses, reattaching the steering wheel linkage, reattaching the pitman arm, and finally the idler arm. The pitman arm will be torqued down correctly after the system is filled, bled, and checked for leaks. The final tasks bill be to reattach the left splash shield, hood prop, and stabilizer bar (as this interferes with the hex socket required for pitman arm).

Thank you to those who answered my questions, gave guidance and insight. There are other Sheppard steering gear repair documents and videos out there, but the M83P2 as installed on my M1151A1 could not be found. I hope this writeup with help someone in the future.

Number and supplier of this "kit" and I for one will give you 5 STARS!

 

[HoveringHMMWV]

It’s a super inclusive kit purchased from Amazon. The kit, I believe, covers a complete rebuild (although I just needed the sector shaft seals, dust boot, dust cap and snap ring). I will provide the link shortly.

 

[HoveringHMMWV]

Here’s the link which I can’t take credit for. Thanks to @rcamacho for the original link.

Amazon.com

 

[HoveringHMMWV]

Victory beverage (Old Fashion w/ chocolate bitters) to celebrate a labor intensive MTC procedure. Just hoping it doesn’t spring a leak!

 

[TNDRIVER]

Here’s the link which I can’t take credit for. Thanks to @rcamacho for the original link.

Amazon.com

GREAT write up! As promised, FIVE STARS.