Transfer case concerns

[Rb999]

Love,love,love this site. Already been a huge help with daystar lift. Was planning on changing all fluids to mobile 1. So far I don't have the dreaded acuator leak. Don't want it. Any chance going to the synthetic in the transfer case might cause a leak. Just thinking I should leave regular dyno in it just to be safe. 2003 v8. I've searched a ton of threads, don't necessary see a connection. Thanks for the help.

 

[BlackWorksInc]

Should cause any issues, synthetic oils and sealing technology have come a long long way. That being said I run Amsoil Synthetic Differential fluid in the front, rear, and transfer case with no leaks.

 

[Stuck CAPS]

Should cause any issues, synthetic oils and sealing technology have come a long long way. That being said I run Amsoil Synthetic Differential fluid in the front, rear, and transfer case with no leaks.

That and synthetic oil won't CAUSE leaks. For that to happen, a leak has to exist already, so the lower viscosity of synthetic oil allows the flow rate to increase, making a previously existent leak more apparent.

 

[BlackWorksInc]

That and synthetic oil won't CAUSE leaks. For that to happen, a leak has to exist already, so the lower viscosity of synthetic oil allows the flow rate to increase, making a previously existent leak more apparent.

I remember hearing a LONG time ago that the synthetic compounds actually did something to old sealing technology. But we're talking like a long long time ago.

 

[Rb999]

Most people who have had the leak seem to chalk it up to not enough regular use in all modes. I'm not hearing anyone jump in with a direct connection to synthetics. Guess that means I'll make the switch. Thanks!

 

[Stuck CAPS]

Most people who have had the leak seem to chalk it up to not enough regular use in all modes. I'm not hearing anyone jump in with a direct connection to synthetics. Guess that means I'll make the switch. Thanks!

Get that oil swapped, go get wheeling and take some pics!

 

[ebg18t]

20+ years ago before half the members of this board were born there was a rash of marketing and speculation that you couldn't run synthetic oil in vehicles that were previously running Dino oil. There was claims of seals leaking to engine failures. There was very little truth behind it.

I do recall something about seals that were dry were swelling when synthetics were used due to some of the additive packages in the synthetic oils back in the day. I don't know the truth behind it though.

In all reality switching to synthetics is no problem. I have switched over to full synthetics and truck runs great. The primary reason I run synthetic is longer service intervals. The Dino oils today offer plenty if protection and if the vehicle is not being used under severe conditions and is maintained regularly Dino oil is just fine.

 

[jambone]

More anecdotal evidence...

I bought a 2006 V8 SR5 4WD with 98k miles on it. Switched the differentials and transfer case to Mobil 1 synthetic gear oil. I also switched the engine oil to Mobil 1 synthetic. 2 years and 30k miles later, no leaks or issues to report.

I also lock the center diff and go into 4LO periodically, per advice found on this board.

 

[4runnerAzGuy]

Yea most people covered what i was going to say. I think you will be fine switching. If you have seeping or anything now though i would think that synthetic might make that more apparent, so might go from seeping to small visible leak. If you dont have a leak now though switching to synthetic wont cause one. I think just trying to use all modes of 4wd as often as u can is the biggest thing to prevent issues as long as u can.

 

[03_4x4Runner]

I switched to Mobil 1 synthetic on my 03 in 2007 at 28k miles. Changed it again with Mobil 1 in 2011 at 65k miles. My actuator leak started shortly after that. I do not know if the leak is caused by the Synthetic lube or not. Looking back if I could start over again I would just use synthetic in the front and rear dif and just use regular lube in the transfer case. It may not have made a difference one way or another. I switched to synthetic before all these transfer case leaks were starting to show up.

 

[Kmvreter]

... at 65k miles. My actuator leak started shortly after that...

How often do you use/exercise 4L and the CDL?

 

[03_4x4Runner]

How often do you use/exercise 4L and the CDL?

I have done a lot of desert exploring over the years. Some days it would get cycled hi to lo and cdl maybe 20 times depending on the trail but normally not that often. I would say I probably averaged 15 off road trips a year since 03.

 

[BlackWorksInc]

20+ years ago before half the members of this board were born there was a rash of marketing and speculation that you couldn't run synthetic oil in vehicles that were previously running Dino oil. There was claims of seals leaking to engine failures. There was very little truth behind it.

I do recall something about seals that were dry were swelling when synthetics were used due to some of the additive packages in the synthetic oils back in the day. I don't know the truth behind it though.

In all reality switching to synthetics is no problem. I have switched over to full synthetics and truck runs great. The primary reason I run synthetic is longer service intervals. The Dino oils today offer plenty if protection and if the vehicle is not being used under severe conditions and is maintained regularly Dino oil is just fine.

The swelling seals due to additives are mainly what I heard. Like I said it was stuff from 20-30 years ago that I don't give much thought, every now and then you hear someone pop up asking if its safe to use synthetics because of this old rumor and I can't help but smile to myself. I find it entertaining how some old wivestales seem to persist even in this day and age where almost all vehicles run synthetics.

 

[Rb999]

transfer case concerns

I think I'm gonna go for it and run the mobil 1. Thanks for all the input. I added a pic. Not enough 4runners on here with the gray cladding and blue paint. I must say I'm loving it more and more. When the 4runner first came out with the unpainted sides, I hated it. Now I own one and love it. Go figure.