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turboL
Active Member
the steps to cheack your hubs for proper operation are as follows.
1. take the front wheels off. (this can be done without takin the wheels off but its easier to inspect parts)
2. behind the disc brakes there are two lines. one is labeled abs and the other is the vacumm line that opertaes the hubs. inspect the entire line for any cracks or breaks as even the smallest crack in one line will cause both hubs to not lock. normally the cracks will be close to the wheel where the line turns with the wheel. i replaced the line with one about 4 inches longer to solve this problem. if u have to replace the line, standard vaccum hose will work but its must be tigth on all the connectors.
3. if the lines are good, then follow the line up to the nearest plastic connector and unhook the line. attack a vacumm guage to the line.
4. start the truck, then have a friend switch it over to four wheel drive. As u watch the vacuum guage, it should read about 50 pounds of vaccum during the switch and once the hubs are locked it should read about 20 psi and stay there. if it dosent stay at around 20 psi or higher re-inspacet the vacumm lines.
1. take the front wheels off. (this can be done without takin the wheels off but its easier to inspect parts)
2. behind the disc brakes there are two lines. one is labeled abs and the other is the vacumm line that opertaes the hubs. inspect the entire line for any cracks or breaks as even the smallest crack in one line will cause both hubs to not lock. normally the cracks will be close to the wheel where the line turns with the wheel. i replaced the line with one about 4 inches longer to solve this problem. if u have to replace the line, standard vaccum hose will work but its must be tigth on all the connectors.
3. if the lines are good, then follow the line up to the nearest plastic connector and unhook the line. attack a vacumm guage to the line.
4. start the truck, then have a friend switch it over to four wheel drive. As u watch the vacuum guage, it should read about 50 pounds of vaccum during the switch and once the hubs are locked it should read about 20 psi and stay there. if it dosent stay at around 20 psi or higher re-inspacet the vacumm lines.
