papabeach
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ADD System Defeat + Manual Hubs
Reference articles:
Have you "Defeated the ADD System"? - YotaTech Forums
Toyota Tech: Defeating the ADD System
After having my ADD system fail on me twice I am done with it. I probably should have defeated the system when I added my manual hubs but I liked the idea of the ADD system keeping my front diffs from constantly spinning. The first time it failed the vacuum lines melted as they were too the headers. This second time I am not entirely sure what happened but the actuator collar got stuck, preventing the fork from moving and the 4WD indicator light sensor wire harness got ripped in half. I am not sure how this happened but I was wheeling in some rocky terrain at Uwharrie, NC on Daniel and I distinctly remember taking a hard hit that knocked my alignment/toe off a bit (steering wheel turned slightly to left) and am wondering if the harness got loose and subsequently wrapped up in the axle or something else. Because I have front ARB air locker I was able to engage it and have 3-wheel drive (w/front driver axle) which did get me unstuck but I didn't want to ride like this all day for fear of breaking something. When I got everything torn apart the collar was easy to unstick by rotating the passenger axle back and forth a couple times while gently prying on the collar with my finger and it popped back into position. Maybe the vacuum lines were acting up again but I said screw it and followed the directions in the articles above to keep the diff actuator engaged at all times.
I drained the diff, and then it was easy enough to remove the actuator (4 bolts for actuator and 1 bolt for vacuum line harness, all 12mm). Only a little bit more fluid drained out. I had a hose clamp on hand and clamped it down to keep the fork in the locked position. Cleaned up the mating surfaces, reapplied some FIPG and put it back together, filled up new fluid and done. Drive shafts are constantly moving now but the system is more reliable now. Just have to keep up with manual hub maintenance.
For now I am planning to keep all of the stock vacuum lines/etc in place until I am sure things are good to go might remove them later but it seems like unnecessary work right now. The last piece of the puzzle is fixing the wiring (optional if I want to have the 4WD light work on the dash). Rather than fully repairing the plugs (not a lot of space to work on wiring and reconnecting, I am wondering if I can simply remove the upstream connector and twist the two wires together then snip the wires on the actuator plug to keep them from flopping around. Or do I need to repair the harness and reconnect?
Diff actuator sensor plug/wire
Upstream wire harness connector
The attached articles hint at wiring the upstream two wires together but these write-ups are for a year/different model I think and I am not familiar with how this is wired. Mine is a 99 with a J-shifter TCase (now triple sticks J)
Any ideas? [MENTION=10169]TheDurk[/MENTION], [MENTION=102606]infamousRNR[/MENTION], [MENTION=120071]mtbtim[/MENTION], [MENTION=28464]eimkeith[/MENTION], [MENTION=148218]JZiggy[/MENTION]
Reference articles:
Have you "Defeated the ADD System"? - YotaTech Forums
Toyota Tech: Defeating the ADD System
After having my ADD system fail on me twice I am done with it. I probably should have defeated the system when I added my manual hubs but I liked the idea of the ADD system keeping my front diffs from constantly spinning. The first time it failed the vacuum lines melted as they were too the headers. This second time I am not entirely sure what happened but the actuator collar got stuck, preventing the fork from moving and the 4WD indicator light sensor wire harness got ripped in half. I am not sure how this happened but I was wheeling in some rocky terrain at Uwharrie, NC on Daniel and I distinctly remember taking a hard hit that knocked my alignment/toe off a bit (steering wheel turned slightly to left) and am wondering if the harness got loose and subsequently wrapped up in the axle or something else. Because I have front ARB air locker I was able to engage it and have 3-wheel drive (w/front driver axle) which did get me unstuck but I didn't want to ride like this all day for fear of breaking something. When I got everything torn apart the collar was easy to unstick by rotating the passenger axle back and forth a couple times while gently prying on the collar with my finger and it popped back into position. Maybe the vacuum lines were acting up again but I said screw it and followed the directions in the articles above to keep the diff actuator engaged at all times.
I drained the diff, and then it was easy enough to remove the actuator (4 bolts for actuator and 1 bolt for vacuum line harness, all 12mm). Only a little bit more fluid drained out. I had a hose clamp on hand and clamped it down to keep the fork in the locked position. Cleaned up the mating surfaces, reapplied some FIPG and put it back together, filled up new fluid and done. Drive shafts are constantly moving now but the system is more reliable now. Just have to keep up with manual hub maintenance.
For now I am planning to keep all of the stock vacuum lines/etc in place until I am sure things are good to go might remove them later but it seems like unnecessary work right now. The last piece of the puzzle is fixing the wiring (optional if I want to have the 4WD light work on the dash). Rather than fully repairing the plugs (not a lot of space to work on wiring and reconnecting, I am wondering if I can simply remove the upstream connector and twist the two wires together then snip the wires on the actuator plug to keep them from flopping around. Or do I need to repair the harness and reconnect?
Diff actuator sensor plug/wire
Upstream wire harness connector
The attached articles hint at wiring the upstream two wires together but these write-ups are for a year/different model I think and I am not familiar with how this is wired. Mine is a 99 with a J-shifter TCase (now triple sticks J)
Any ideas? [MENTION=10169]TheDurk[/MENTION], [MENTION=102606]infamousRNR[/MENTION], [MENTION=120071]mtbtim[/MENTION], [MENTION=28464]eimkeith[/MENTION], [MENTION=148218]JZiggy[/MENTION]
