I by-passed my in radiator tranny cooler

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dandemedi
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Location: San Diego, CA

tranny cooler bypassed

Postby dandemedi » Wed Jul 21, 2010 12:41 am

Done about 450 miles ago. small slip remains but only once in a while. This slip will probably stay. I drained the pan 4 times, about 20 qts. Installed an aftermarket cooler in line with existing cooler (comes with tow package vehicle). If Pathfinder doesn't come with tow package, I believe the cooler is still on vehicle but not connected. It is in front of radiator and evaporator, just behind the grill on left side as your facing the engine (black in color).
My wife is the one who noticed the shutter (slip). She Took car to mechanic twice and he didn't notice it. When I came home after a month she showed me the shutter. I would not have noticed it if she didn't tell me when it happened. She is responsible for advising me, which led me to :wink: :D the subsequent fix.
Good luck to all. I try to tell every pathfinder owner I come in contact with.

Thanks again,


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admiral
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Postby admiral » Wed Jul 21, 2010 2:24 pm

I looked some consumer reports of this issue and found a class action lawsuit. I sent the link to this thread and the comsumer reports to www.jalopnik.com.

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rragpaoa
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2008+

Postby rragpaoa » Thu Jul 22, 2010 11:22 am

I have a 2008+ with 60K miles and I off road mine pretty hard. Only changed the tranny oil and coolant at 30K. Going to change them again soon. Just checked the fluids and no problems so far. Not sure if I'm going to do the mod. Maybe the 2008+ have better internals? I've noticed that Nissan has made some slight modifications (I owned a 2005 Pathy beforehand)

asgard
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Postby asgard » Wed Jul 28, 2010 4:35 pm

Just completed the bye pass today. I didn't use the pipe connector just re-routed the pipe from the oil cooler to the feed pipe and used the longer pipe to close loop the rad cooler.

Is this the way most do it or am I missing something and should have used the pipe connector.

Looks tidy and no cost option.

I changed the radiator fluid - Prestone long life - good for 5 years.

also did the transfer case fluid change.

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Budrbean
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Re: 2008+

Postby Budrbean » Thu Jul 29, 2010 12:18 am

rragpaoa wrote:I have a 2008+ with 60K miles and I off road mine pretty hard. Only changed the tranny oil and coolant at 30K. Going to change them again soon. Just checked the fluids and no problems so far. Not sure if I'm going to do the mod. Maybe the 2008+ have better internals? I've noticed that Nissan has made some slight modifications (I owned a 2005 Pathy beforehand)
  • What you fail to realize is that if you check the fluid and its milky, then its too late....damage is done. Unless you happen to catch it right at the very moment it happens. Its cheap insurance that will save you $3k in repairs.

WheatBread
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Postby WheatBread » Thu Jul 29, 2010 5:34 am

asgard wrote:Just completed the bye pass today. I didn't use the pipe connector just re-routed the pipe from the oil cooler to the feed pipe and used the longer pipe to close loop the rad cooler.

Is this the way most do it or am I missing something and should have used the pipe connector.

Looks tidy and no cost option.

I changed the radiator fluid - Prestone long life - good for 5 years.

also did the transfer case fluid change.
thats what I did

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rragpaoa
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Re: 2008+

Postby rragpaoa » Thu Jul 29, 2010 12:48 pm

Budrbean wrote:
What you fail to realize is that if you check the fluid and its milky, then its too late....damage is done. Unless you happen to catch it right at the very moment it happens. Its cheap insurance that will save you $3k in repairs.
Understand. I check my fluids religiously. What I asked was that if the 2008+ Pathfinders had a design changed that fixed the issues since I haven't seen a problem with the 08 and above, and it seems that the plumbing is a bit different. The engineers put it there for a reason, and from looking at the 2010 models, it's still there. Shouldn't they have learned by now if it is truly a problem? Has there been any long term effects and studies, in all weather conditions, that this mod does not effect the tranny? Reason being is that I drive in 110+ degrees in summer (Vegas/Arizona) and 0- degrees winters (Colorado) every year. I change my fluids every 30K miles. That's insurance for me.

Maybe the 2005-2007 really had problems, thus the bypass is necessary.

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08Datsun
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Postby 08Datsun » Thu Jul 29, 2010 3:12 pm

The radiator assembly itself is identical between 2005-2010. I called Courtesy Parts early in the year, and they knew of no change in the radiator along the way. If Nissan made a change in the materials, they didn't seem to tell anyone. I'd love to think that they'd fixed the problem, but my '08 was still affected by the fuel sender problems like the older models. We have the actual data and part numbers to let us know when that update was made. There is no such data on a radiator update to which I'm aware.

The plumbing is indeed different starting in 2008. The aux. cooler is now on the driver's side instead of the passenger's. I had assumed this was to make room for the electric fan in front of the radiator for the V8 instead of the rear like the V6.

When the 2007's started having the problem and I had no info that told me a change had been made, I did the bypass on my '08. I happened to have Hayden heavy duty engine oil cooler laying around that I used to replace the radiator cooler, then ran it in series with the aux. cooler. I also had a 10" Hayden fan laying around I've since added. Since I had the parts and the time, I went ahead and did it. I hate the idea of a minor leak causing a major breakdown.

I've been told by a retired transmission engineer, that the radiator mounted oil to water cooler is very beneficial. It is much more efficient than an oil to air cooler and being mounted in the cool tank, essentially "quenches" the hot tranny fluid coming out of the torque converter. I hated to bypass it, but that's why I added a second cooler. I've driven it in +-115 degrees with no problem. We've towed in the Sierras so far no problem. I was told by the engineer that the over-cooling in the winter is a myth. The radiator never gets hot enough in the bottom tank to warm the tranny fluid.

If someone finds some actual data that the 2008+ radiator has been fixed, I'd sure love to hear about it.

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rragpaoa
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Postby rragpaoa » Thu Jul 29, 2010 4:28 pm

Thx 08Datsun for the info on your 08.

The concept of "quenching" the tranny fluid appears to be right, since water is a better transfer medium than air. There has been some real number testing here: http://www.thenewx.org/forum/showthread.php?t=30287 where ultimately the radiator-atf cooler is the most effective than just the atf cooler alone. They recommend that if you do the bypass, add a secondary atf cooler.

Again, i'm betting (hoping) that the Nissan engineers had fixed the problems on the 08+ Pathfinders. I have been searching on both the Xterra and Frontier forums to see if any late models have the problems and so far none.

I'm even more concern of the bypass since I have the V8 which puts out an additional 100lbs of torque, and when I off road and going <30mph, I want the best cooling possible.

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CiK
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Postby CiK » Thu Jul 29, 2010 8:08 pm

First things first........this is a long read, but I am thankful for everybody taking the time to help each other out on this subject. I plan to do the bypass this week on my 06 Pathfinder.

I have read that there is a 2nd transmission cooler inline. How would I know if I had this? Is it stock on all Pathfinders? What does it look like? Where would I find it? I plan on towing with the Pathfinder and would like to know that I am protected in some fashion.

WheatBread
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Postby WheatBread » Fri Jul 30, 2010 4:59 am

the is a cooler in the radiator, this is the one that you'll bypass, then there is an external cooler in front of the radiator on the passenger side

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CiK
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Postby CiK » Fri Jul 30, 2010 5:51 am

WheatBread wrote: then there is an external cooler in front of the radiator on the passenger side
Is this external cooler in front of the radiator on the passenger side standard on all 2006 Pathfinder models? Or just the ones with towing package?

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disallow
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Postby disallow » Fri Jul 30, 2010 6:07 am

CiK wrote:
WheatBread wrote: then there is an external cooler in front of the radiator on the passenger side
Is this external cooler in front of the radiator on the passenger side standard on all 2006 Pathfinder models? Or just the ones with towing package?
All R51 Pathfinders (at least in North America) come with the towing package, and hence come with the external oil/air cooler.

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myriad46
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Postby myriad46 » Fri Jul 30, 2010 6:25 am

Has anyone had their pathfinder in for service after doing the bypass? I just had my tranny and radiator replaced due to "the issue" and thought that now would be a perfect time to do the bypass. My concern is that I have another 18 months of warranty left and don't know if the dealer would give me a stink, if there should be a problem with something.

WheatBread
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Postby WheatBread » Fri Jul 30, 2010 6:37 am

WheatBread wrote:
asgard wrote:Just completed the bye pass today. I didn't use the pipe connector just re-routed the pipe from the oil cooler to the feed pipe and used the longer pipe to close loop the rad cooler.

Is this the way most do it or am I missing something and should have used the pipe connector.

Looks tidy and no cost option.

I changed the radiator fluid - Prestone long life - good for 5 years.

also did the transfer case fluid change.
thats what I did
if you perform this bypass it is super easy to reverse before you take it in to the stealer


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