I by-passed my in radiator tranny cooler

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qqqq
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Postby qqqq » Tue Aug 02, 2016 7:45 am

I am currently at 71K miles on my 2010 Pathfinder. It runs great, no issues whatsoever. I drain&fill transmission fluid every 15K miles, and replaced coolant at 60K miles. Drained fluids look (surprisingly) very clean, so I know there is no contamination issue as of yet. As I near 80K warranty point, I wonder what the best course of action is. Here are my questions:

1. Has anyone seen/heard of 2010 model years being affected? I know they are covered by settlement, but have there been reported failures yet on 2010?
2. Leave it as is – yes or no?
3. If no, fix now or closer to 80K point?
4. If no, what’s the best way to eliminate the problem in the future – bypass or rad replacement?

I have not towed yet, but plan on towing in the future. Also, live in Colorado and do a lot of mountain/off road driving if that helps. Towing would be over the same mountain passes. I am less concerned about money (i.e. free bypass vs. $100 for rad) then bullet proof reliability in the future to make sure coolant and transmission fluid don’t mix.

Really appreciate your opinions! Thank you.


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disallow
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Postby disallow » Tue Aug 02, 2016 8:44 am

qqqq wrote: 1. Has anyone seen/heard of 2010 model years being affected? I know they are covered by settlement, but have there been reported failures yet on 2010?
2. Leave it as is – yes or no?
3. If no, fix now or closer to 80K point?
4. If no, what’s the best way to eliminate the problem in the future – bypass or rad replacement?
Yes we've seen 2010s affected.
I wouldn't leave it.
Bypass now.
Long term replace the rad.

:)

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Postby qqqq » Tue Aug 02, 2016 9:53 am

Thanks, Terry. I kind of expected this answer, just wasn’t sure if 2010s have been spotted by now.

My main concern and the reason why I have not done bypass so far is warranty coverage. I can see the dealer not wanting to replace transmission for free at say 79K miles if I did either the bypass or rad replacement (in case the damage is already done right now just not visible yet).

If I were to do bypass now, at what point would you recommend rad replacement?

Thanks.

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Postby eieio » Tue Aug 02, 2016 10:15 am

qqqq wrote:Thanks, Terry. I kind of expected this answer, just wasn’t sure if 2010s have been spotted by now.

My main concern and the reason why I have not done bypass so far is warranty coverage. I can see the dealer not wanting to replace transmission for free at say 79K miles if I did either the bypass or rad replacement (in case the damage is already done right now just not visible yet).

If I were to do bypass now, at what point would you recommend rad replacement?

Thanks.
i'm with Terry on this, if for no other reason, to avoid dealing with the dealership
under your circumstances (off-road & mountain pass towing), i'd replace the radiator now just for the piece of mind that you will be able to proceed with your activities without the risk of damage from either contamination or overheating the transmission from heavy load/slow driving
by-passing the radiator in the interim would be a good idea

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disallow
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Postby disallow » Tue Aug 02, 2016 10:29 am

+1 on this reply.

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Postby qqqq » Tue Aug 02, 2016 10:57 am

Thank you both!

So here is what I am thinking and couple of follow up questions. I cannot do bypass right now for free – I looked and the hoses are different on my 2010 compared to diagrams in this thread on earlier models. I would need to buy couple of feet of the hose, plus end caps. No big deal, probably around $5, but if the rad has to go, I don’t see the point of doing the bypass. Agree?

I looked at radiators online. RockAuto as well as Amazon carry the same 4 brands – Spectra, TYC, OSC, and APDI. Is there a consensus on this forum which of these is GUARANTEED not to have the contamination problem? I am making assumption they are all made in China, maybe even by the same company, but would love to know if one is preferred vs. the others. They are all in the same price range ($100-$120).

As far as contamination goes – is there a sense within the community as to how long it takes between contamination to occur (unnoticed), and signs being visible (milkshake in the coolant)? In other words, if I don’t see it yet, and I fix it today (either bypass or rad replacement), is there a chance I will still end up with damaged transmission 5K miles down the road because coolant is already in the transmission today? Just wondering if there is certain amount of time/mileage to watch out for after which you can safely assume the problem is gone for good.

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Postby eieio » Tue Aug 02, 2016 11:35 am

qqqq wrote:Thank you both!

So here is what I am thinking and couple of follow up questions. I cannot do bypass right now for free – I looked and the hoses are different on my 2010 compared to diagrams in this thread on earlier models. I would need to buy couple of feet of the hose, plus end caps. No big deal, probably around $5, but if the rad has to go, I don’t see the point of doing the bypass. Agree?

I looked at radiators online. RockAuto as well as Amazon carry the same 4 brands – Spectra, TYC, OSC, and APDI. Is there a consensus on this forum which of these is GUARANTEED not to have the contamination problem? I am making assumption they are all made in China, maybe even by the same company, but would love to know if one is preferred vs. the others. They are all in the same price range ($100-$120).

As far as contamination goes – is there a sense within the community as to how long it takes between contamination to occur (unnoticed), and signs being visible (milkshake in the coolant)? In other words, if I don’t see it yet, and I fix it today (either bypass or rad replacement), is there a chance I will still end up with damaged transmission 5K miles down the road because coolant is already in the transmission today? Just wondering if there is certain amount of time/mileage to watch out for after which you can safely assume the problem is gone for good.
the only 100% guarantee would be the by-pass
that said, this type of radiator is in VERY common useage among MANY car & truck manufacturers
apparently the only reason the Nissan issue has come to light is a manufacturing defect in the radiators that they had made for them
there are probably millions of vehicles on the planet with radiators with this design that have had (and will have) no problems
as far as contamination indications, that would probably be dependent on the severity of seal leakage between the internal cooler & the radiator it is contained within, and the amount of time since the leakage began
close inspection of the transmission fluid from a warmed up transmission (a drained sample - not what you may see on the dipstick) should reveal contamination
otherwise, a sample could probably be analyzed by a lab
the one factor that is a sure thing: once it happens, it's done!

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Postby Dwyck99 » Tue Aug 02, 2016 12:22 pm

eieio wrote:
qqqq wrote:Thank you both!

So here is what I am thinking and couple of follow up questions. I cannot do bypass right now for free – I looked and the hoses are different on my 2010 compared to diagrams in this thread on earlier models. I would need to buy couple of feet of the hose, plus end caps. No big deal, probably around $5, but if the rad has to go, I don’t see the point of doing the bypass. Agree?

I looked at radiators online. RockAuto as well as Amazon carry the same 4 brands – Spectra, TYC, OSC, and APDI. Is there a consensus on this forum which of these is GUARANTEED not to have the contamination problem? I am making assumption they are all made in China, maybe even by the same company, but would love to know if one is preferred vs. the others. They are all in the same price range ($100-$120).

As far as contamination goes – is there a sense within the community as to how long it takes between contamination to occur (unnoticed), and signs being visible (milkshake in the coolant)? In other words, if I don’t see it yet, and I fix it today (either bypass or rad replacement), is there a chance I will still end up with damaged transmission 5K miles down the road because coolant is already in the transmission today? Just wondering if there is certain amount of time/mileage to watch out for after which you can safely assume the problem is gone for good.
the only 100% guarantee would be the by-pass
that said, this type of radiator is in VERY common useage among MANY car & truck manufacturers
apparently the only reason the Nissan issue has come to light is a manufacturing defect in the radiators that they had made for them
there are probably millions of vehicles on the planet with radiators with this design that have had (and will have) no problems
as far as contamination indications, that would probably be dependent on the severity of seal leakage between the internal cooler & the radiator it is contained within, and the amount of time since the leakage began
close inspection of the transmission fluid from a warmed up transmission (a drained sample - not what you may see on the dipstick) should reveal contamination
otherwise, a sample could probably be analyzed by a lab
the one factor that is a sure thing: once it happens, it's done!


I just bought an 08 2WD LE and I am curious as well if there is a particular brand and model number of radiator that folks here have found to be good for avoiding the inner tank breaking open? I live in Texas and do not do any towing... would simple doing the bypass probably be ideal for me, and given the hot weather here, is there any risk in using the external cooler only? What do I look for on the radiator to determine if it is one that is known to be at risk for breaking and contaminating? Also, can you or anyone direct me to a very good video or photo write-up of doing the bypass? Thx

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Postby smj999smj » Tue Aug 02, 2016 12:53 pm

The common part numbers of those that fail are as follows: 21460-EA215, 21460-EA265 and 21460-EA200. This would be on a Calsonic sticker on the top tank of the radiator. These are factory installed radiators; we have not heard of any issues with the aftermarket replacements. Of the aftermarket choices, Spectra Premium is probably the most popular, but, whether they are any better than the sub-$100 models listed on Ebay is debatable. I have seen one Denso radiator develop a leak at a small crack in the bottom tank, but it was hard to say if it was a manufacturer's defect or just something that occurred during shipping. My 06 has an Ebay-sourced radiator that I paid $92 for about four years ago; my 08 had a Koyorad that I got a deal on for $50 from someone who bought it then sold their Pathy about two years ago. Both are doing fine and fit perfectly.

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Postby Dwyck99 » Tue Aug 02, 2016 1:44 pm

smj999smj wrote:The common part numbers of those that fail are as follows: 21460-EA215, 21460-EA265 and 21460-EA200. This would be on a Calsonic sticker on the top tank of the radiator. These are factory installed radiators; we have not heard of any issues with the aftermarket replacements. Of the aftermarket choices, Spectra Premium is probably the most popular, but, whether they are any better than the sub-$100 models listed on Ebay is debatable. I have seen one Denso radiator develop a leak at a small crack in the bottom tank, but it was hard to say if it was a manufacturer's defect or just something that occurred during shipping. My 06 has an Ebay-sourced radiator that I paid $92 for about four years ago; my 08 had a Koyorad that I got a deal on for $50 from someone who bought it then sold their Pathy about two years ago. Both are doing fine and fit perfectly.

Ok thanks for the good info. So being that I live in Texas and do no towing, would the bypass be just a good an option as replacing the radiator assuming it still has the Calsonic... I'll have to check when wifey gets home, it's an 08 with 155K on it so possibly it's already been changed anyway. And can you guide me to a write up or video for this?

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Postby smj999smj » Wed Aug 03, 2016 3:24 pm

You could get away with just doing the bypass, as the auxiliary trans cooler seems to do a pretty good job. I'm still a proponent of replacing the radiator, but there are many who have bypassed and even tow without any problems.
There should be a write up somewhere on these forums instructing how to do it. Most are for the 05-07 models, which are a little easier than the 2008 and later models, but that's simple as well. You'll need about two feet of 5/16" (8MM) transmission cooler hose, some miniature hose clamps, a plastic tie strap and two, 5/16" caps. You will probably not lose enough ATF to have to add, but it still wouldn't hurt to have a quart of Nissanmatic Type "J" or "S" ATF or equivalent (Castrol Transmax Import Multi-vehicle or Valvoline Maxlife ATF) just in case. Remove the front skid plate. If you look at the cooler hoses, there is a left and right side hose (left being the driver's side). The left hose goes from the radiator cooler fitting to a metal hose union at the left side of the radiator. Remove the cooler hose from this union and from the radiator fitting. Remove the right side hose from the radiator fitting to the metal cooler line. You can blow clear or flush the radiator's cooler if you wish to remove the trans fluid from the cooler. Install the two caps on the radiator's fittings and install/tighten clamps. Install the new cooler hose to the union at the left side of the radiator and clamp. Run the hose to the metal line and cut to size, install and clamp. Use the plastic tie strap to secure the hose so it's not flopping all around. Clean off the residual oil. Start the vehicle, top of the ATF and check for leaks. If all is good, reinstall the skid plate. BTW, with the skid plate out of the way, it's a good time to change the oil and filter.

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Postby Dwyck99 » Wed Aug 03, 2016 7:36 pm

smj999smj wrote:You could get away with just doing the bypass, as the auxiliary trans cooler seems to do a pretty good job. I'm still a proponent of replacing the radiator, but there are many who have bypassed and even tow without any problems.
There should be a write up somewhere on these forums instructing how to do it. Most are for the 05-07 models, which are a little easier than the 2008 and later models, but that's simple as well. You'll need about two feet of 5/16" (8MM) transmission cooler hose, some miniature hose clamps, a plastic tie strap and two, 5/16" caps. You will probably not lose enough ATF to have to add, but it still wouldn't hurt to have a quart of Nissanmatic Type "J" or "S" ATF or equivalent (Castrol Transmax Import Multi-vehicle or Valvoline Maxlife ATF) just in case. Remove the front skid plate. If you look at the cooler hoses, there is a left and right side hose (left being the driver's side). The left hose goes from the radiator cooler fitting to a metal hose union at the left side of the radiator. Remove the cooler hose from this union and from the radiator fitting. Remove the right side hose from the radiator fitting to the metal cooler line. You can blow clear or flush the radiator's cooler if you wish to remove the trans fluid from the cooler. Install the two caps on the radiator's fittings and install/tighten clamps. Install the new cooler hose to the union at the left side of the radiator and clamp. Run the hose to the metal line and cut to size, install and clamp. Use the plastic tie strap to secure the hose so it's not flopping all around. Clean off the residual oil. Start the vehicle, top of the ATF and check for leaks. If all is good, reinstall the skid plate. BTW, with the skid plate out of the way, it's a good time to change the oil and filter.
Ok thx this will be my next project after I get the CMS replaced.

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Postby qqqq » Tue Oct 18, 2016 4:16 pm

Hi guys,

so I decided to just do the bypass now and maybe next summer replace the radiator. I searched the threads and it appears there are 2 ways to go about it: 1. purchase transmission line and cut it to size, and it replaces current lines; 2. keep existing tubes and just buy a metal connector (not sure if that's the right word for it) and connect them.

I don't want to make it more complicated than it really is, but was wondering if one method is preferred over another. Method 2 with connector seems a little easier but might restrict the flow of the fluid, though not really sure about it.

Thank you for your help!

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Tranny bypass

Postby bhull3 » Wed Dec 07, 2016 3:24 pm

I'm a newbie to the Pathfinder. Just bought my '08 in August (144K). I found out about the intermix issue from a Nissan mechanic as I was considering buying the car. He told me what to look for (foaming in the radiator). There was none and it looked like the previous owners had addressed the intermix issue as there was an external cooler in front of the radiator. Took a photo of it and sent it to the mechanic (who works for a Nissan dealership) and he confirmed that was the case. Put 7K miles on the car, towing a 5x8 trailer twice. Last week I came across a diagram of the cooling layout for the the Pathfinder and to my horror - it showed the external cooler as part of the stock configuration. Nissan mechanic never responded back to my call; took it to another mechanic who did the bypass for me. Told me the radiator and tranny looked relatively new, so the intermix had probably already occurred on this vehicle. My question: the mechanic who did the bypass just routed the lines through to the stock external cooler instead of installing another one. He told me it was more than adequate for our climate and the light towing I do. For you experts, is that the case? and...I freaking LOVE this car!

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Postby smj999smj » Wed Dec 07, 2016 6:26 pm

Auxiliary trans coolers come standard on the North American R51's. They are on the passenger side, in front of the A/C condenser, on the 05-07 models and on the driver's side on 08-and-later models. There are a lot of people who simply re-route the lines to bypass the radiator's internal cooler and leave it at just that, without issue. It cools the trans fluid just fine by itself but does lose the ability of the radiator's internal cooler to warm the fluid and maintain it in the 175-200 degree F. range. There is no need to add another external cooler; if it was a concern, one would be better off replacing the radiator and using its cooler with the external cooler rather than run two external coolers and not pass through the radiator's cooler. If one tows heavy or lives in an area of extreme heat or cold, I would recommend replacing the radiator.


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