A little help fixing my 4wd system?

[thegipper]

I had a VSV go bad a couple months ago. I also couldn't find the part or part number on any websites. A couple members on here said that a new VSV is over $500! Thankfully I have a donor truck and stole one of the VSV's off of it.

Your best bet is to try to find one in a junkyard, in fact, I'd grab both just in case (I believe they are interchangeable). I'm sure the yard will sell it for dirt cheap since they probably don't know how expensive they are new.

Here is my recent post: 4wd decided to quit working

Unfortunately, the PN is still unknown. Maybe someone can chime and share it if they have it.

 

[phattyduck]

Sorry to ask but I’ve been looking for hours. I followed your testing advice to find the fault of my 97 4 runner not engaging 4wd. I have a faulty vsv. I can not find a part number, diagram or parts seller that lists the vsv for sale. Any help is appreciated.

They are all over eBay. Search for Toyota ADD VSV - make sure you get the right ones as they were a bit different through the years.

-Charlie

 

[Anton97]

Thank you for the eBay search help. Having the right search term made all the difference. I am so appreciative for this forum. We have had our 97 4 runner since new and it’s an aging member of the family, but still a much loved daily driver.

Before I order parts, I’d like to run my issue past anyone interested in commenting. This is my first time posting so I apologize if I am not asking in the right place.

Our 4 runner has the 6 cylinder, auto trans, 275k miles. We live in Nova Scotia so we need 4wd in winter. About 4 years ago the green 4wd light would not come on and it would not engage 4wd. I found a post suggesting switching the hoses on the vsv’s to check. After doing this, it all seemed to work fine again. Now it is doing it again, no green light, no engagement. Switching hoses did not help. I went through the steps to locate the problem and it seems to be the vsv’s.

Now the question- I found this paragraph on the off road article mentioned on this forum suggesting removing the vsv’s all together by connecting the vacuum line from the intake to the blue vacuum line to the actuator. Upon doing this, everything works. Green light goes on, 4h and 4low engage and disengage fine. If this is now working, what am I missing. Am I destroying something, killing gas mileage?? I will do the right thing and get the parts I need but I’m just curious.

Here is the paragraph- Permanently locking the ADD unit: There are 2 hoses connected to the ADD actuator. The vacuum line on the passenger side of the actuator puts shaft into the diff and the other side removes it. I removed the vacuum tank and vacuum switches. Then I connected a single vacuum line to the passenger side of the actuator to keep it locked. Then I and caped the driver side tube. This will prevent the ADD system from unlocking. The switches can be found behind the battery on the inside right fender, the vacuum tank is in front of the front right tire under the fender. Be sure to cap the vacuum feed from the engine to the switches or remove the "T" feeding it all together. I have found that the transfer case shifts much easer without the ADD system.

 

[Bad Luck]

Thank you for the eBay search help. Having the right search term made all the difference. I am so appreciative for this forum. We have had our 97 4 runner since new and it’s an aging member of the family, but still a much loved daily driver.

Before I order parts, I’d like to run my issue past anyone interested in commenting. This is my first time posting so I apologize if I am not asking in the right place.

Our 4 runner has the 6 cylinder, auto trans, 275k miles. We live in Nova Scotia so we need 4wd in winter. About 4 years ago the green 4wd light would not come on and it would not engage 4wd. I found a post suggesting switching the hoses on the vsv’s to check. After doing this, it all seemed to work fine again. Now it is doing it again, no green light, no engagement. Switching hoses did not help. I went through the steps to locate the problem and it seems to be the vsv’s.

Now the question- I found this paragraph on the off road article mentioned on this forum suggesting removing the vsv’s all together by connecting the vacuum line from the intake to the blue vacuum line to the actuator. Upon doing this, everything works. Green light goes on, 4h and 4low engage and disengage fine. If this is now working, what am I missing. Am I destroying something, killing gas mileage?? I will do the right thing and get the parts I need but I’m just curious.

Here is the paragraph- Permanently locking the ADD unit: There are 2 hoses connected to the ADD actuator. The vacuum line on the passenger side of the actuator puts shaft into the diff and the other side removes it. I removed the vacuum tank and vacuum switches. Then I connected a single vacuum line to the passenger side of the actuator to keep it locked. Then I and caped the driver side tube. This will prevent the ADD system from unlocking. The switches can be found behind the battery on the inside right fender, the vacuum tank is in front of the front right tire under the fender. Be sure to cap the vacuum feed from the engine to the switches or remove the "T" feeding it all together. I have found that the transfer case shifts much easer without the ADD system.

If you bypass the VSV's and lock the ADD in on dry roads or pavement you cause extra stress in the front axle and transfer case which will likely cause transfer case failure. It will also cause your mpg's to suffer. If you want to do this procedure until you get a VSV then don't drive it on pavement or hard dry surfaces where binding can occur.

EDIT: I was thinking the transfer case was in 4wd as well. Like phattyduck corrected me in the next post, if the transfer case is in 2wd there won't be any binding and you can drive on pavement. You'll have worse fuel economy but that's it.

 

[phattyduck]

If you bypass the VSV's and lock the ADD in on dry roads or pavement you cause extra stress in the front axle and transfer case which will likely cause transfer case failure. It will also cause your mpg's to suffer. If you want to do this procedure until you get a VSV then don't drive it on pavement or hard dry surfaces where binding can occur.

No, no... it won't hurt anything as long as the transfer case is in 2WD.

It is the equivalent of driving with front hubs locked on a manual-hub 4WD vehicle.

The front axles, differential and driveshaft will all be linked and spinning at all times if the ADD is locked in the engaged position. It will cause lower MPGs and higher wear (minor) on the front driveshaft. The hubs/CVs always spin (whether ADD is working or not), so you don't save anything there...

-Charlie

 

[Bad Luck]

No, no... it won't hurt anything as long as the transfer case is in 2WD.

It is the equivalent of driving with front hubs locked on a manual-hub 4WD vehicle.

The front axles, differential and driveshaft will all be linked and spinning at all times if the ADD is locked in the engaged position. It will cause lower MPGs and higher wear (minor) on the front driveshaft. The hubs/CVs always spin (whether ADD is working or not), so you don't save anything there...

-Charlie

You're right. I completely spaced on that. I was thinking of having the transfer case engaged all the time as well. Thanks for the correction!