| Fleetwood Motorhome Power Gear Salon Slide-Out Modification |
| Many Fleetwood Class A motorhomes built roughly in the 2000-2005 time frame were supplied with an under-powered motor/gear assembly on the driver's side main salon slide-out. This means that when the slide-out is retracted, the motor can stall initially upon trying to lift up the inner edge of the slide-out. If the motor is allowed to stall, the current draw goes up dramatically as does generated heat, and the motor may burn out. Also at risk is the slide-out controller relay board. Many of us have tried lightening the load in a vain attempt to cure this. The following describes an analysis of why this happens, and how it can be avoided successfully. The affected design is a Power Gear-supplied dual "rack and pinion" drive, with a center-located motor/gear drive assembly showing p/n 523432. This design was changed for model year 2005 or 2006, with a higher-powered assembly showing p/n 522176 (now discontinued), and then the 523900. A number of Fleetwood owners had the new assembly installed for free either under warranty, by special consideration, or during rallies. But most of us have been denied the fix unless we could have demonstrated to the dealer that the motor completely stalled, while still under warranty. The new assembly, if bought directly from Power Gear, costs around $400 including shipping. You might be noticing increasingly sluggish operation of slide-out retraction, as motor armature and bearing wear take its toll, and rollers require more effort to turn. As a side note, until the motor can retract the slide without slowing way down, you may want to start the lift then move to another slide to allow some time for the motor armature to distribute the heat, and finish the retraction after that. Some owners with the more powerful motors are reporting stripped gears, which implies that the stronger motor is too much for the same light-duty gears. Motor/Gear Assembly It is possible to open up the motor/gear assembly, but unless you're proficient at microsurgery you'd best not attempt it, and the performance gain might be marginal anyway. With the assembly disconnected (fairly straightforward removal), after removing a half-dozen already-loose screws, separating the two aluminum halves is easy enough. But upon doing so, you will allow two small roller bearing races to drop their bearings haphazardly, especially if the lubrication is minimal as it was with ours. Successful reassembly would require packing the races with grease and lining up the bearings around the race walls to allow unobstructed reinsertion of the shafts. There is plenty of grease in the housing, but most of it where it can't do any good, so you can push some into the gear teeth where it will be greatly appreciated. At this point you can remove the motor armature from the back end after sliding off the rubber boot and removing the motor brake. The armature will undoubtedly show signs of distress such as grooves worn into the commutator or discoloration due to heat. Using 600 grit sandpaper or a fine flat file, you can spin the armature and resurface the commutator. The brushes will probably still be okay, but will have to be carefully pulled back to allow insertion of the armature back into the motor housing. After successful reassembly, you may notice little improvement in operation, but the re-greasing of the gears will be helpful to minimize future wear. Slide-Out Seal One of the chores in bringing in a slide-out is to separate the rubber bulb seal on the inside edge of the slide-out from the aluminum surface it mates with. This can take some effort, especially on a slide that has been pushed down into firm contact, and when the rubber has some age to it. Using 303 Aerospace Protectant spray liberally on both mating surfaces reduces the effort to separate these parts, in addition to presumably protecting the rubber. |
Inner Edge Lift
By far, the hardest task the motor faces is lifting the inner edge of the slide-out up when first
retracting. The design is literally a nylon sled runner on dry carpet, rather than using actual bearing
surfaces. This causes a great deal of friction in addition to requiring lift energy. Unfortunately, there's
really nothing that can be done here, because a redesign would involve the slide being physically
removed, and that's a whole other topic completely. And lubrication is not going to help here because
the nylon will just "wipe itself off" on the carpet, potentially creating dark stains on the carpet.
Plastic Roller Replacements
Here's where a large improvement can be made, enough to allow the slide motor to be able to push the
sled over the carpet without stalling, by removing a couple of sources of additional friction.
Original Outer Rollers Original Inner Rollers
As you can see, the rollers that support the entire weight of the slide-out (and its contents) are plastic,
rather than actual bearings. This means that there is a substantial amount of friction in these eight
rollers when spinning on a dry steel "cap screw" axle, even when new. Spraying the recommended
dry silicone lubricant is unlikely to help here because that lubricant doesn't work well under load, and
it's almost impossible to get lubricant on the axle shafts anyway because of the design. And these
rollers do wear, both on the outer surface and on the inner surface, in addition to wearing down the
steel shafts. The above pictures show appreciable wear after less than 200 cycles.
New Outer Bearings New Inner Bearings
What we did was replace the plastic rollers with double-sealed (both sides) steel ball bearing
assemblies. What this requires is to get ball bearings with an outside diameter of 2" to fit on a 1/2"
shaft. The best bearing found was one with a 2" OD, 1" ID (McMaster-Carr p/n 60355K61 $10 each)
that is 1/2" wide, fully sealed, and can be used for both the inner and outer sets of rollers.
Outer Bearings
The outer bearings require a spacer such as McMaster-Carr's 92510A365 (aluminum 1" x 1/2" x 3/4"
$8 each), which when pressed flush to one side (mounted as the inner side) closely replicates the
spacing of the original roller. An additional 1/2" ID 1/8" thick galvanized washer can be used on the
outside to take up all of the axial slack and give added support to the bolt. Alternately, an aluminum
spacer could be cut from 1" x 1/2" 6061 rod stock, with a length of 7/8" to match the entire bolt
shoulder.
With the slide-out opened almost all the way (but not with the rubber bulb seal wedged), the new
outer bearings can be installed sitting by the outside of the motorhome, although it's easier done from
underneath, requiring only a 9/16" ratchet and a pair of "channel lock" pliers. The bolt actually takes a
7/32" hex allen wrench, but most allen wrenches are too tall to fit in-between the two bolt heads.
Inner Bearings
For the inner rollers, it's a little trickier, because there must be enough clearance in the center of the
shaft for the rack teeth, meaning a 1" OD spacer cannot be used fully across the shaft. Also, the
bearings have to be separate to allow jockeying them into position in their cage.
Sealed Ball Bearings w/Spacer 3/4" OD Steel Shaft Spacers Lift with 3/4" thick redwood
Finally, pressure must be relieved from the shaft bolt to allow removal. You can see in the above
picture that a 3/4" thick knot-free redwood slat about 32" long and 4" wide was wedged into the track
to allow lifting the inner rail just enough to unload pressure on the bolt, without pressing on the rack
teeth. A 3/4" wrench and matching ratchet with deep socket allows easy removal and re-tightening of
the bolt.
Using the same bearings and aluminum spacers as for the outer rollers, three additional spacers per
side were required to best match the original spacings. Steel spacers were cut from a 3/4" OD x 1/2"
ID steel rod using a chop saw. Reassembly begins with a 1/2" wide spacer, the bearing/spacer with
the shoulder toward the middle, a 1" wide steel spacer allowing clearance for the rack gear teeth
above, the second bearing with the shoulder again toward the middle, and finally a second 1/2" wide
spacer. Although axial loads are minimal and the original thought was to use sections of 1/2" PVC
irrigation riser for the three spacers, I'd recommend steel to avoid worrying about spacer failure
forever.
One unexpected snag was that the driver's side forward inner roller shaft couldn't be removed without
cutting it in half, due to a clearance problem because the bolt had been inserted from the outside in
(although it could have easily have been avoided at the factory). A 5-1/2" long 1/2" galvanized cap
screw took its place. Although there was wear on all the steel shafts, none was so bad to preclude its
reuse because they are no longer wear surfaces.
The bottom line was under $150 in parts per slide-out (we did both sides) for the new rollers, with
some spacer fabrication and press-fitting (hammering) required. With parts in hand and a heavy-duty
lift in place, the whole job could be done in a half hour, including cutting out the one boxed-in bolt
with a reciprocating saw and metal-cutting blade. The new design will never need lubrication, and
there's no more groaning and squealing.
Upgrading Wiring
The above approaches have proven adequate enough not to require any further measures yet. We've
not had to resort to running heavy duty wires in parallel with the existing wiring, from the controller
board directly to the motor wires, bypassing the motor connector, but this might provide just enough
additional voltage (thus current) to the motor under heavy load to cure the problem if the above
methods are deemed insufficient. If ever necessary, we'll revise this web page and report the results.
Return to Main Discovery Page
By far, the hardest task the motor faces is lifting the inner edge of the slide-out up when first
retracting. The design is literally a nylon sled runner on dry carpet, rather than using actual bearing
surfaces. This causes a great deal of friction in addition to requiring lift energy. Unfortunately, there's
really nothing that can be done here, because a redesign would involve the slide being physically
removed, and that's a whole other topic completely. And lubrication is not going to help here because
the nylon will just "wipe itself off" on the carpet, potentially creating dark stains on the carpet.
Plastic Roller Replacements
Here's where a large improvement can be made, enough to allow the slide motor to be able to push the
sled over the carpet without stalling, by removing a couple of sources of additional friction.
Original Outer Rollers Original Inner Rollers
As you can see, the rollers that support the entire weight of the slide-out (and its contents) are plastic,
rather than actual bearings. This means that there is a substantial amount of friction in these eight
rollers when spinning on a dry steel "cap screw" axle, even when new. Spraying the recommended
dry silicone lubricant is unlikely to help here because that lubricant doesn't work well under load, and
it's almost impossible to get lubricant on the axle shafts anyway because of the design. And these
rollers do wear, both on the outer surface and on the inner surface, in addition to wearing down the
steel shafts. The above pictures show appreciable wear after less than 200 cycles.
New Outer Bearings New Inner Bearings
What we did was replace the plastic rollers with double-sealed (both sides) steel ball bearing
assemblies. What this requires is to get ball bearings with an outside diameter of 2" to fit on a 1/2"
shaft. The best bearing found was one with a 2" OD, 1" ID (McMaster-Carr p/n 60355K61 $10 each)
that is 1/2" wide, fully sealed, and can be used for both the inner and outer sets of rollers.
Outer Bearings
The outer bearings require a spacer such as McMaster-Carr's 92510A365 (aluminum 1" x 1/2" x 3/4"
$8 each), which when pressed flush to one side (mounted as the inner side) closely replicates the
spacing of the original roller. An additional 1/2" ID 1/8" thick galvanized washer can be used on the
outside to take up all of the axial slack and give added support to the bolt. Alternately, an aluminum
spacer could be cut from 1" x 1/2" 6061 rod stock, with a length of 7/8" to match the entire bolt
shoulder.
With the slide-out opened almost all the way (but not with the rubber bulb seal wedged), the new
outer bearings can be installed sitting by the outside of the motorhome, although it's easier done from
underneath, requiring only a 9/16" ratchet and a pair of "channel lock" pliers. The bolt actually takes a
7/32" hex allen wrench, but most allen wrenches are too tall to fit in-between the two bolt heads.
Inner Bearings
For the inner rollers, it's a little trickier, because there must be enough clearance in the center of the
shaft for the rack teeth, meaning a 1" OD spacer cannot be used fully across the shaft. Also, the
bearings have to be separate to allow jockeying them into position in their cage.
Sealed Ball Bearings w/Spacer 3/4" OD Steel Shaft Spacers Lift with 3/4" thick redwood
Finally, pressure must be relieved from the shaft bolt to allow removal. You can see in the above
picture that a 3/4" thick knot-free redwood slat about 32" long and 4" wide was wedged into the track
to allow lifting the inner rail just enough to unload pressure on the bolt, without pressing on the rack
teeth. A 3/4" wrench and matching ratchet with deep socket allows easy removal and re-tightening of
the bolt.
Using the same bearings and aluminum spacers as for the outer rollers, three additional spacers per
side were required to best match the original spacings. Steel spacers were cut from a 3/4" OD x 1/2"
ID steel rod using a chop saw. Reassembly begins with a 1/2" wide spacer, the bearing/spacer with
the shoulder toward the middle, a 1" wide steel spacer allowing clearance for the rack gear teeth
above, the second bearing with the shoulder again toward the middle, and finally a second 1/2" wide
spacer. Although axial loads are minimal and the original thought was to use sections of 1/2" PVC
irrigation riser for the three spacers, I'd recommend steel to avoid worrying about spacer failure
forever.
One unexpected snag was that the driver's side forward inner roller shaft couldn't be removed without
cutting it in half, due to a clearance problem because the bolt had been inserted from the outside in
(although it could have easily have been avoided at the factory). A 5-1/2" long 1/2" galvanized cap
screw took its place. Although there was wear on all the steel shafts, none was so bad to preclude its
reuse because they are no longer wear surfaces.
The bottom line was under $150 in parts per slide-out (we did both sides) for the new rollers, with
some spacer fabrication and press-fitting (hammering) required. With parts in hand and a heavy-duty
lift in place, the whole job could be done in a half hour, including cutting out the one boxed-in bolt
with a reciprocating saw and metal-cutting blade. The new design will never need lubrication, and
there's no more groaning and squealing.
Upgrading Wiring
The above approaches have proven adequate enough not to require any further measures yet. We've
not had to resort to running heavy duty wires in parallel with the existing wiring, from the controller
board directly to the motor wires, bypassing the motor connector, but this might provide just enough
additional voltage (thus current) to the motor under heavy load to cure the problem if the above
methods are deemed insufficient. If ever necessary, we'll revise this web page and report the results.
Return to Main Discovery Page
