Transit_Bus_Towing_Instructions.pdf

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Towing Instructions

GILLIG recommends flatbedding a disabled bus. If towing is necessary, flat towing from the front with a fixed tow bar is recommended. Towing with the front end raised should be a last resort. GILLIG does not recommend towing from the rear. Review the Warnings and Caution below before towing the bus.

�WARNING

• Towing should not be attempted without proper training.

• No towing operation should be attempted which is unsafe in any way for the towing vehicle, operator, bystanders, or other motorists.

• Vehicle towing must be done in compliance with all state and local laws. Safety chains must be used in conjunction with the primary lifting/towing equipment. Secure or remove all loose or protruding parts of a damaged bus. To avoid possible personal injury, DO NOT get under a bus that is being lifted by the towing equipment unless the bus is properly blocked and supported. The GILLIG Low Floor should never be towed more than a few feet without first disconnecting the driveline.

• An auxiliary air supply of 100 to 120 psi should be provided to the bus while it is being towed, so that adequate air is available to operate the brakes. Any time the air pressure falls below 65 psi, the parking brake engages automatically. The Low Floor bus is fitted with emergency air fittings at the front and rear behind the bumpers. This allows operation of the brakes and suspension while the bus is being towed. The front emergency air fitting has a cap/filter assembly which must be removed prior to hooking up an external air source. Be sure to reinstall the cap/ filter assembly after towing the bus.

• Never tow a vehicle over 35 miles per hour (55 kilometers per hour).

� CAUTION

Remove the driveshaft or both axle shafts before towing the bus! Towing with the driveline rotating will damage the transmission. Clean up any spilled oil.

General Information

Attachment D - Sarasota County Transit BusAttachment 4

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Flat Towing {All Wheels on the Ground)

A fixed tow bar (Figure 1-8 or Figure 1-10) should be used only for flat towing the Low Floor. If your bus has the streamlined (BRT) front structure, you must use the

BRT tow bar in order to avoid damaging the front cap lower closeout (see Figure 1-9).

See Figure 1-11 for ground clearance and towing height for BRT tow bars.

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Front Bumper Channel

Do not use standard tow bar on buses with BRT front cap closeout.

Figure 1-8, GILLIG Fixed Tow Bar for Standard Low Floor

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Figure 1-9, Incorrect Tow Bar on BRT Bus

8cAUTION Figure 1-10, GILLIG Fixed Tow Bar for BRT Buses

Do not try to lift the front wheels with a tow bar. GILLIG tow bars are for flat towing with all four wheels on the ground only. For towing with the front wheels raised, see important information on the following page •

Figure 1-11, BRT Tow Bar Ground Clearance and Towing Height

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Towing with Front Wheels Raised (Hooking)

@cAUTION Do not try to lift the front wheels with a tow bar. GILLIG tow bars are for flat towing with all four wheels on the ground only.

If it is necessary to tow with the front of the bus elevated, the front axle must be securely chained so that the shock absorbers and air springs are not damaged. Chain the front axle as follows.

1. Support the frame securely with blocks or jack stands.

2. Make sure that wheels are pointing straight ahead.

3. Working from behind the front axle, secure the chains around the tie rod to the structure behind, as shown in Figure 1-12. Minimum chain size is 3/8".

4. Lift the front of the bus and verify that the chains are supporting the axle.

5. Use towing points fl or towing points© as shown in Figure 1-12.

Secure Chains Tightly

Figure 1-12, Tow Points and Chaining Front Axle

Driveshaft Removal

Refer to Figure 1-13.

1. Park the bus on level ground and block the wheels to prevent movement of the bus.

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2. Tum off the battery disconnect switch. Use a battery disconnect switch lockout device so that power isn't inadvertently turned back on while you're working.

�WARNING

The driveshaft is heavy. Support it securely before the capscrews are removed.

a CAUTION To prevent damage to the needle bearings during removal, DO NOT let the bearing cups drop on the floor.

3. Working at the differential yoke, remove and discard the capscrews and the bearing straps. Pull the driveshaft away from the yoke, being careful to keep the bearing cups on the spider. Use caution to ensure the needle bearings inside the caps are not disturbed and do not fall out of the caps. If the needle bearings fall out, they must be cleaned, lubricated, and reassembled in the cap.

4. Repeat step 3 for the U-joint at the transmission yoke. Remove the driveshaft from the bus.

0NOTICE

Some drivetrain combinations may require over-raising the suspension to allow for additional clearance needed to compress the driveshaft for removal.

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Li-joint

Transmission Yoke

Grease Fittings

Grease Fitting

Dust Seal

Slip Yoke

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Bearing Strap

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Yoke Shaft

Differential Yoke

Figure 1-13, Driveshaft

Axle Shaft Removal b:, CAUTION Do not use a chisel or wedge to loosen the axle shafts and dowels. The chisel or wedge can damage the hub, shafts, or oil seals.

1. Remove the nuts and washers from the hub studs.

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2. Hold a 1-1/2" (38 mm) diameter brass drift or brass hammer against the center of the axle shaft, inside the round driving lugs. See Figure 1-14.

ffi WARNING Wear safe eye protection. Do not hit the round driving lugs on the head of the axle shafts as the lugs can break and cause injury.

3. Use a 5-6 lb (2-3 kg) hammer to strike the end of the drift to loosen the axle shaft and the tapered dowels.

4. Mark each axle shaft before it is removed from the axle assembly.

5. Remove the tapered dowels and separate the axle shafts from the main axle hub assembly. Three threaded holes may be provided in the axle shaft flange for use with puller screws, if necessary.

6. Install a cover over the open end of each axle assembly hub where an axle shaft was removed.

�CAUTION

Before towing the bus, make sure that the driveshaft or both axle shafts are removed.

Figure 1-14,Axle Shaft Removal