I wasn't sure if there was enough room to pull the actuator out all the way for the shift fork (probably the wrong word but the part that moves the engagement mechanism in the ADD). If there is then that will save the OP a ton of work!
4WD issues..
- Thread starter giguchan
- Start date
fullmoonguru
New member
+1 on the vacuum lines.
giguchan
Senior Member
An update on this issue..
I dropped off my truck the other day only to get it back today and after $1k late the problem still isn't fixed.
The dealer diagnosed the issue as a Bad actuator and apparently not available through Toyo anymore so they had to go aftermarket. They replaced the the front differential actuator and it still does not work as it's supposed to.
The Good folks on this Board suggested that it might be the Vacuum portion of the system. They're telling me that isn't right.
More when i return on Monday.
I dropped off my truck the other day only to get it back today and after $1k late the problem still isn't fixed.
The dealer diagnosed the issue as a Bad actuator and apparently not available through Toyo anymore so they had to go aftermarket. They replaced the the front differential actuator and it still does not work as it's supposed to.
The Good folks on this Board suggested that it might be the Vacuum portion of the system. They're telling me that isn't right.
More when i return on Monday.
JustTroItIn
Member
Are you sure you are hearing the relay activate?
Get a volt meter and measure if you have 12v to the VSV's. One should get 12v in 2wd and the other in 4wd. If you have 12v to each one when the shift lever is in the appropriate position pull the vacuum line and see if you actually have vacuum. If one does not get 12v then you have a 4wd switch bad, relay bad, or wiring issue. If each has 12v in the appropriate position and you don't have vacuum, then bad VSV. If you do have vacuum then you have a vacuum leak or the actuator is working and the indicator switch in the diff is bad.
If your 2wd VSV is working and your 4wd VSV is not you can put the truck in 4wd, switch the vacuum lines between the 2 VSV, 4wd should then activate and the indicator on the dash will light. This will at least verify that 4wd is mechanically sound.
Get a volt meter and measure if you have 12v to the VSV's. One should get 12v in 2wd and the other in 4wd. If you have 12v to each one when the shift lever is in the appropriate position pull the vacuum line and see if you actually have vacuum. If one does not get 12v then you have a 4wd switch bad, relay bad, or wiring issue. If each has 12v in the appropriate position and you don't have vacuum, then bad VSV. If you do have vacuum then you have a vacuum leak or the actuator is working and the indicator switch in the diff is bad.
If your 2wd VSV is working and your 4wd VSV is not you can put the truck in 4wd, switch the vacuum lines between the 2 VSV, 4wd should then activate and the indicator on the dash will light. This will at least verify that 4wd is mechanically sound.
giguchan
Senior Member
Hey there,
I do hear the relay switching in the kick panel on the passenger side. when i go to switch in 4WD and back out again. But No Illumination on the panel.
Thank you for the suggestion. If i can get the time i'll try your suggestion. Can you tell me if the Actuator is visible from under the Truck? I would like to see exactly what they are doing under there.
It's going back tomorrow.
The advisor also said something about the OEM parts from Toyota are long not available. so they had to go aftermarket.
I do hear the relay switching in the kick panel on the passenger side. when i go to switch in 4WD and back out again. But No Illumination on the panel.
Thank you for the suggestion. If i can get the time i'll try your suggestion. Can you tell me if the Actuator is visible from under the Truck? I would like to see exactly what they are doing under there.
It's going back tomorrow.
The advisor also said something about the OEM parts from Toyota are long not available. so they had to go aftermarket.
TravThePro
New member
This ended up being the problem with my truck as well. I initially thought it was my ADD actuator, but I had no vacuum going through either of the lines. The truck mostly sitting for 3 years seized both of my VSVs.
OP you should really just pull both long hoses for the VSVs and feel with your finger if one gets vacuum in 2WD and one gets vacuum when you click it to 4WD.
I can offer further testing advice for the ADD actuator if at least of them does get vacuum while you check the VSVs.
giguchan
Senior Member
I heard from the dealer today.. The NEW Tech who did the latest Troubleshooting Came back with the same diagnosis.
giguchan
Senior Member
Thanks for all of the Trouble shooting tips. Currently the truck is at the dealer awaiting parts. Believe it or not I'm told that from here on out there will be no charge. I believe this to because of the Misdiagnosis and because i already paid them.
giguchan
Senior Member
All!!
We have finally achieved success! I just brought my Truck back from the shop and everything works as it should..
All of you who said the "VSV For ADD Binding" Congratulate yourself for a proper diagnosis.
Basically they Disassembled and replaced VSV 4WD CONTROL.
We don't have much sand or anything around here to perform a proper test without spending a lot of money for a permit. I'll figure something out.
Thanks again. Next? I'm going Exhaust shopping- from up front to the tail pipe.. Gonna be a big Nut
Anybody have any cool SOUNDING ideas?
Total parts replaced/sourced
PN 600-994 Actuator
PN 4140035020 Actuator ASSY
PN 8422235070 Switch TRANSF
PN 0029501281 F.I.P.G TRANS
PN 373523014093 VSV 4WD CONTROL
We have finally achieved success! I just brought my Truck back from the shop and everything works as it should..
All of you who said the "VSV For ADD Binding" Congratulate yourself for a proper diagnosis.
Basically they Disassembled and replaced VSV 4WD CONTROL.
We don't have much sand or anything around here to perform a proper test without spending a lot of money for a permit. I'll figure something out.
Thanks again. Next? I'm going Exhaust shopping- from up front to the tail pipe.. Gonna be a big Nut
Anybody have any cool SOUNDING ideas?
Total parts replaced/sourced
PN 600-994 Actuator
PN 4140035020 Actuator ASSY
PN 8422235070 Switch TRANSF
PN 0029501281 F.I.P.G TRANS
PN 373523014093 VSV 4WD CONTROL
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