Installing the
Grand Classic Master Track System

Don Roberts
(734) 847-8515
jroberts@gte.net


Please note that the rear suspension of the coach should be in good alignment before installing this system, if it is not wearing the rear tires unevenly the rear wheels are probably in good alignment. This system is not designed to correct bent bogies or worn pins.

Any work done on your GMC Motor Home should be done in a safe manner, use all safety precautions: safety glasses, good jacking equipment, timbers or strong jack stands, common sense, the proper tools, etc. The job requires about six hours and will go much easier if there are two working at it. At least one who is mechanically inclined and the other to hold and fetch.

After jacking the coach up and blocking it in a secure manner, drop the air pressure in the air bags, and remove the leading rear wheels; remove the brake drums as per instructions in the GMC Motor Home Shop Manual; remove the four 3/8 inch bolts which secure the drum backings and spindle to the leading bogie arm. Using the longer grade 8 bolts supplied secure the Master Track axle bracket to the inboard side of the bogie arms with the large bolt hole down. (For coaches with disk brakes the axle bracket is bolted on the inboard side of the backing plate.) The brakes can now be reassembled with the brake drums properlv installed to the axles. These procedures must be done on each side.

On the right (passenger's) side of the coach make a mark on the frame 14 inches in back of the back edge of the frame cross member between the gasoline tanks. On the left (driver's) side make a mark on the frame 8 7/8 inches in back of that same cross member. Clamp or use jacks to hold the Master Track cross member to the bottom of the coach frame with the front edges of the Master Track cross member mounting brackets on the lines you made on the frame. Yes, that means that the Master Track cross member will not be straight across.

The next steps will involve drilling and you are cautioned to be certain that any wires or other essential parts of the motor home are not going to be damaged. Also you are reminded that drill chips are often sharp and hot so be careful. A suggestion here is that a 2X4 about 6 feet long as a lever and a block of wood for a fulcrum can be used to apply steady pressure to the drill.

Once you have the Master Track cross member centered on the frame and exactly on the lines on the frame (Check and recheck this) drill a 13/32 hole straight up through the frame using one of the mountng bracket holes as a guide. Install a bolt finger tight to hold things in alignment. Do this on both sides and be sure the holes are straight. Drill the other hole in each mounting bracket.

Before mounting Master Track frame plates coat the top side with grease, silicone, or roof cement to seal out moisture. Drop the Master Track cross member on one side and fasten the frame plate to the holes you have just made - finger tight only. All nuts are to be on the top of the frame and use the lock washers provided. Do the same on the other side. Straighten the frame plates on the frame, tighten the two bolts on each side. Drill the remaining four holes on each side of the frame, install the bolts and tighlen securely.

The right side Master Track Panard rod. - tracking bar or tie rod, if you prefer - is secured to the axle bracket with a bolt and rubber bushings and will eventually be fastened to the front left side of the Master Track cross member by an adjustable fitting, but not now. For now use wire and fasten the rod to the Master Track cross member. Do the same for the left side. (The left side bar will be secured to the rear of the Master Track cross member.)

Reinstall the leading rear wheels, torque the nuts, and re-inflate the air bags. Drive to a level place where you can let the motorhome coast or be gently braked to an easy stop and where you do not have to turn for a couple of coach lengths. On each side in turn, reach under the coach, unwire the Panard rod and run the adjustable fitting in or out until the bolt will slip through its hole easily. Install the lock washer and nut and tighten securely. Tighhten the adjustable fitting jam nut also. Do the same on both sides. This method should hold the rear wheels in good alignment - if they were before.

Now enjoy easy driving with the trucks and cars in multi-lane rush-hour traffic; or on rutted roads or anywhere
(c) November 1996, Don Roberts


Graphics by Al Chernof


Both arms and bracket


Arm to wheel connection


Close up brace and bracket


Opposite side


Cross member and two arms


Both arms and brace (Driver's side)


Brace and two cross over arms


Close-up brace and wheel


Crossover and brace


Connection to Bogie