2006 Pathfinder transmission bypass

The Gas and Diesel Engines - VQ40De, VK56DE, YD25DDTi, V9X, Transmission, Transfer Case, Oil, Differentials, Axles, Exhaust...

Moderator: volvite

outback
Posts: 1
Joined: Wed Aug 25, 2010 3:48 pm
Location: oregon

2006 Pathfinder transmission bypass

Postby outback » Wed Aug 25, 2010 3:56 pm

ok, first post for me. i just bought a 2006 pathfinder S and i'm now discovering this transmission/coolant issue. now if i do the bypass method does that mean the transmission no longer has a means for cooling? would i be better off adding an aftermarket transmission cooler?

forgive me if this issue has been beaten to death.

thanks for your input


User avatar
SilverGhost
Posts: 321
Joined: Wed Jan 10, 2007 6:23 am
Location: Houston, TX

Re: 2006 Pathfinder transmission bypass

Postby SilverGhost » Wed Aug 25, 2010 4:10 pm

outback wrote:ok, first post for me. i just bought a 2006 pathfinder S and i'm now discovering this transmission/coolant issue. now if i do the bypass method does that mean the transmission no longer has a means for cooling? would i be better off adding an aftermarket transmission cooler?

forgive me if this issue has been beaten to death.

thanks for your input
Short answer - NO! Just read the tons of posts about that on this forum. Your PF ALREADY HAS an external cooler. The one in the radiator is problematic, and most likely ineffective.

User avatar
eieio
Sponsored Member
Posts: 1841
Joined: Fri Jul 17, 2009 6:42 am
Location: Prescott, Az.

Re: 2006 Pathfinder transmission bypass

Postby eieio » Wed Aug 25, 2010 5:01 pm

SilverGhost wrote:
outback wrote:ok, first post for me. i just bought a 2006 pathfinder S and i'm now discovering this transmission/coolant issue. now if i do the bypass method does that mean the transmission no longer has a means for cooling? would i be better off adding an aftermarket transmission cooler?

forgive me if this issue has been beaten to death.

thanks for your input
Short answer - NO! Just read the tons of posts about that on this forum. Your PF ALREADY HAS an external cooler. The one in the radiator is problematic, and most likely ineffective.
SilverGhost, have you done any moderate/heavy towing with the by-pass having been done, and no additional transmission cooling provision?

NVRDONE
Posts: 159
Joined: Wed May 07, 2008 1:35 pm
Location: seattle

Postby NVRDONE » Wed Aug 25, 2010 5:08 pm

As far as towing with out the in radiator cooler, I tow a 19' boat that weighs 4200 #. I did the by pass 2 years ago & so far no problems. The trans fluid is still clean & has no burnt smell.

4x2
Posts: 13
Joined: Wed Aug 25, 2010 6:12 pm

Postby 4x2 » Wed Aug 25, 2010 6:15 pm

Just wanted to point out that the internal atf cooler in the radiator is actually quite effective at cooling the atf fluid according to this guy's data. For those that tow and off road heavy with the bypass, should install another atf cooler.

http://www.thenewx.org/forum/showthread.php?t=30287

User avatar
disallow
Site Admin
Posts: 2820
Joined: Wed Aug 13, 2008 9:02 am
Location: Winnipeg, Canada

Postby disallow » Thu Aug 26, 2010 5:43 pm

4x2 wrote:Just wanted to point out that the internal atf cooler in the radiator is actually quite effective at cooling the atf fluid according to this guy's data. For those that tow and off road heavy with the bypass, should install another atf cooler.

http://www.thenewx.org/forum/showthread.php?t=30287
Geez, this has me thinking I should 'un-bypass' my rad...

User avatar
richardekirby
Posts: 233
Joined: Sun May 09, 2010 7:40 pm
Location: Garland, TX

Postby richardekirby » Thu Aug 26, 2010 6:51 pm

disallow wrote:
4x2 wrote:Just wanted to point out that the internal atf cooler in the radiator is actually quite effective at cooling the atf fluid according to this guy's data. For those that tow and off road heavy with the bypass, should install another atf cooler.

http://www.thenewx.org/forum/showthread.php?t=30287
Geez, this has me thinking I should 'un-bypass' my rad...
That's some impressive data, but I will never have trans fluid running thru my rad again. I would add another external cooler or a cooling fan, or both. I have not done any towing yet and don't have a reason to very much, but I don't want to overheat the trans if I do. I do a fair amount of off-roading, so a fan would be the best thing for me.

4x2
Posts: 13
Joined: Wed Aug 25, 2010 6:12 pm

Postby 4x2 » Fri Aug 27, 2010 7:35 am

Another solution is to replace the radiator with a high quality aftermarket one. The possibility of contamination will be much less than using nissan's defective radiator, while still retain stock cooling capacity.

User avatar
BMXPath
Posts: 361
Joined: Fri Oct 19, 2007 7:55 am
Location: Texas!

Postby BMXPath » Fri Aug 27, 2010 8:33 am

disallow wrote: Geez, this has me thinking I should 'un-bypass' my rad...
Yeah, good luck with that.

Whereas no one has reported overheating problems after doing the bypass, there are more than enough reports of problems with the faulty cooler for those who did NOT bypass.

Go ahead and weigh out what you think is the best option... Especially since you have an '05 which is probably the most problematic year for the rad/ trans leak.

User avatar
disallow
Site Admin
Posts: 2820
Joined: Wed Aug 13, 2008 9:02 am
Location: Winnipeg, Canada

Postby disallow » Fri Aug 27, 2010 9:58 am

BMXPath wrote:
disallow wrote: Geez, this has me thinking I should 'un-bypass' my rad...
Yeah, good luck with that.

Whereas no one has reported overheating problems after doing the bypass, there are more than enough reports of problems with the faulty cooler for those who did NOT bypass.

Go ahead and weigh out what you think is the best option... Especially since you have an '05 which is probably the most problematic year for the rad/ trans leak.
Now that the cooler has been sitting empty for some time, I probably won't just hook it back up.

But I may go the route of pre-emptive replacement of the rad with a Spectra Premium.

t

User avatar
eieio
Sponsored Member
Posts: 1841
Joined: Fri Jul 17, 2009 6:42 am
Location: Prescott, Az.

Postby eieio » Fri Aug 27, 2010 10:35 am

NVRDONE wrote:As far as towing with out the in radiator cooler, I tow a 19' boat that weighs 4200 #. I did the by pass 2 years ago & so far no problems. The trans fluid is still clean & has no burnt smell.
thanks NVRDONE :)
i'd be interested in hearing from others who have done the by-pass (as i have), and their towing experiences without any further trans cooling mods.

4x2
Posts: 13
Joined: Wed Aug 25, 2010 6:12 pm

Postby 4x2 » Fri Aug 27, 2010 12:08 pm

disallow wrote:
BMXPath wrote:
disallow wrote: Geez, this has me thinking I should 'un-bypass' my rad...
Yeah, good luck with that.

Whereas no one has reported overheating problems after doing the bypass, there are more than enough reports of problems with the faulty cooler for those who did NOT bypass.

Go ahead and weigh out what you think is the best option... Especially since you have an '05 which is probably the most problematic year for the rad/ trans leak.
Now that the cooler has been sitting empty for some time, I probably won't just hook it back up.

But I may go the route of pre-emptive replacement of the rad with a Spectra Premium.

t
Yea simply doing the bypass is just swapping a problem for another. You even mention that your transmission fluid had a burnt smell to it. Excessive heat degrades transmission overtime, so problems may not show up for a while, but by then its too late.
disallow wrote:After letting my drained trans fluid settle for a few days, I can see that its pretty dark, and it also has a bit of a burnt smell to it. Probably from towing my gargantuan trailer in high winds when the TC wouldn't lock up. I'm also by-passed, with no additional cooler other than the factory air/oil cooler.


coom1986
Posts: 194
Joined: Fri Aug 08, 2008 12:29 pm

Postby coom1986 » Fri Aug 27, 2010 1:47 pm

Guys just some food for thought,,temperatures in our region can vary from 43-50+ Celcius..thats 110F -122F temperatures,,ambient temperatures the car is reading..With almost 50% humidity minimum..so in reality its more..

With offorading or stop and go traffic,,you can imagine the temperatures the tranny and the rest of the parts get into.. But ive never seen any nissan budge over the quarter mark on the temp gauge..We might be getting a differnet cooling system compared to you guys but for those who tow heavy stuff,,might wanna add a fan at least..

User avatar
eieio
Sponsored Member
Posts: 1841
Joined: Fri Jul 17, 2009 6:42 am
Location: Prescott, Az.

Postby eieio » Fri Aug 27, 2010 2:11 pm

Just when we thought it was safe............... :(

SHAWNATGERBROCK
Posts: 209
Joined: Fri Sep 01, 2006 4:11 pm
Location: Portland OR

Postby SHAWNATGERBROCK » Wed Sep 01, 2010 3:12 pm

I have been waiting for Koyo or someone to come out with a good full aluminum performance radiator for the Pathfinders ... I doubt it will be soon , probably should do the bypass soon ... But I have also been debating on adding another external cooler , or just running the existing cooler ... or just one larger cooler ...


Return to “R51 Engine, Driveline and Powertrain”