90 Toyota Pickup
02-19-2013, 03:20 PM
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90 Toyota Pickup
1990 Toyota Pickup. I just put new manual hubs (was automatic) on my truck and the 4 wheel drive still isn't working. How can i get the 4x4 working again?
02-19-2013, 03:26 PM
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did you do anything with the diff? you have to somehow engage the front diff, with vacuum and properly working add, or something mechanical like a hose clamp. do a search on how to convert add to manual
02-19-2013, 03:37 PM
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if your 4x4 wasnt working before then it wont work now. you need to either bypass the automatic disconnect in the diff or make it work correctly again. try seaching on google, i found a good article about it but didnt save it
02-19-2013, 03:44 PM
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You didn't have Automatic Hubs. You had/have Automatic Differential Disconnect. There's nothing more yo the hubs than just a plate to keep CV axles fixed onto the spindle. Your front differential has a separation on the drivers side inner axle with a sleeve that joins the two ends via vacuum actuator. Those actuators like to not work over time. Or there's a vacuum leak. Or electrical problem.
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02-19-2013, 04:15 PM
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02-19-2013, 04:44 PM
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02-21-2013, 07:28 AM
#18
Is your 4WD light turning on?
If it is turning on then your front diff is engaging and you need to set both hubs to "lock"
If the light is not coming on you have a problem with your ADD system (most likely a bad Vac line or Vac lines to the VSS actuators put on backwards (They're color coded))
If it is turning on then your front diff is engaging and you need to set both hubs to "lock"
If the light is not coming on you have a problem with your ADD system (most likely a bad Vac line or Vac lines to the VSS actuators put on backwards (They're color coded))
02-21-2013, 08:24 AM
#20
if you are adding manual hubs, then you are most likely trying to bypass the ADD system - otherwise why do it at all?
if this is the case you need to do as the ADD removal process states, and permanently lock the ADD mechanism to the engaged position. i did mine with a hose clamp. all you need to do is pop the cover off, slide the geared sleeve over the stub shaft to the engaged position. when the sleeve is engaged, there is a ~1/2" of shaft exposed where the slide mechanism is attached - just enough room for a hose clamp around the shaft. once installed, it is literally impossible for the sleeve to slide back unless the hose clamp self destructs. as for the vacuum system - plug it off. done.
if your light doesn't come on, it's probably vacuum related. my truck wasn't ADD, but I installed a 4.88 ADD diff - so I can't help there. read the swap guide, your answer should be in there. at the least it will let you know what vac lines to look at - or just trace them up from diff to engine compartment and look at your vac diagram under hood/FSM
if this is the case you need to do as the ADD removal process states, and permanently lock the ADD mechanism to the engaged position. i did mine with a hose clamp. all you need to do is pop the cover off, slide the geared sleeve over the stub shaft to the engaged position. when the sleeve is engaged, there is a ~1/2" of shaft exposed where the slide mechanism is attached - just enough room for a hose clamp around the shaft. once installed, it is literally impossible for the sleeve to slide back unless the hose clamp self destructs. as for the vacuum system - plug it off. done.
if your light doesn't come on, it's probably vacuum related. my truck wasn't ADD, but I installed a 4.88 ADD diff - so I can't help there. read the swap guide, your answer should be in there. at the least it will let you know what vac lines to look at - or just trace them up from diff to engine compartment and look at your vac diagram under hood/FSM
