I by-passed my in radiator tranny cooler

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porksoda
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Postby porksoda » Wed Jul 08, 2015 10:13 pm

wizeguy wrote:Did this bypass today and it was easy! Felt a big burden off my shoulders now.
And it did take longer to pull the shield off then it did the actual hose swap.
bellwilliam wrote:just did the bypass. easier done than describing it. but I did not use any additional parts. no coupler, no hose clamp (reuse original), no zip tie.

you have 2 hoses -
hose A - from external transmission cooler to radiator (passenger side)
hose B - from radiator (driver side) to engine block.


take hose A off radiator (passenger side) and plug into engine block
take hose B off engine block and plug into radiator (passenger side), forming a loop within.

reuse all the old hose and clamp. length is perfect.

Before
Image

After
Image


This is exactly what I did.


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AZ_Path
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Postby AZ_Path » Mon Jul 20, 2015 9:48 am

I'm close to the 80K mile mark and after talking to my mechanic and reading even more around here, I'm convinced that the radiator is more for heating than cooling the transmission fluid. There is speculation that the radiator could be cooling during extreme conditions, but no data to support that yet. So I'm planning to perform the bypass and want to keep an eye on the transmission temp due to where I live and towing a heavy load.

I've found the various inexpensive bluetooth modules that can monitor the vehicle through the OBD2 port, but so far none of them appear to be capable of reading the transmission temperature for our trucks. For those that have been reading it, what tool are you using?

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smj999smj
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Postby smj999smj » Mon Jul 20, 2015 7:36 pm

If it were not for the factory installed, auxiliary trans cooler, the radiator's integral cooler would probably be doing more of the job of actually cooling the oil. Since, the auxiliary cooler takes care of the cooling of the fluid, the radiator's integral cooler serves as an additional cooler if and when it is ever needed, as well as a device to maintain the temperature of the fluid in the 175-200 degree F. range, the temperature range that the transmission oil should be operating within.
I believe those that were monitoring the trans temps were using a Bully Dog, possibly with an additional temp sensor. Hopefully one of them will chime in with what they used.

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AZ_Path
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Postby AZ_Path » Tue Jul 21, 2015 2:47 pm

Well I read a little more and saw that Fossilfuleburner posted some good data on Page 1 and 2 of this thread. http://www.thenissanpath.com/viewtopic.php?t=3357

Maybe the radiator cooler is actually doing some cooling. I should probably just put a new rad in and be done with it. I called my mechanic and he was skeptical that aftermarket radiators have actually fixed the design flaw. He said it can be tough to tell if they have been truly updated or not. The OEM part is almost $600!!!! His price would be ~ $450, but that's still too much.

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eieio
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Postby eieio » Tue Jul 21, 2015 2:54 pm

AZ_Path wrote:Well I read a little more and saw that Fossilfuleburner posted some good data on Page 1 and 2 of this thread. http://www.thenissanpath.com/viewtopic.php?t=3357

Maybe the radiator cooler is actually doing some cooling. I should probably just put a new rad in and be done with it. I called my mechanic and he was skeptical that aftermarket radiators have actually fixed the design flaw. He said it can be tough to tell if they have been truly updated or not. The OEM part is almost $600!!!! His price would be ~ $450, but that's still too much.
it was a manufacturing (Calsonic) flaw, not a design flaw, so the aftermarket companies have nothing to do with it

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AZ_Path
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Postby AZ_Path » Tue Jul 21, 2015 3:24 pm

eieio wrote:it was a manufacturing (Calsonic) flaw, not a design flaw, so the aftermarket companies have nothing to do with it
Thanks, I was wondering about that. Since it was an issue with the seal that makes sense. eieio did you bypass or replace?

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eieio
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Postby eieio » Tue Jul 21, 2015 3:47 pm

AZ_Path wrote:
eieio wrote:it was a manufacturing (Calsonic) flaw, not a design flaw, so the aftermarket companies have nothing to do with it
Thanks, I was wondering about that. Since it was an issue with the seal that makes sense. eieio did you bypass or replace?
i by-passed both of them, as i almost never tow anything
between the two trucks (total of 78K miles combined), I've only towed one time, a small U-Haul trailer

khavel
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Limp mode after "bypass" surgery

Postby khavel » Mon Jul 27, 2015 10:08 am

So its been several months since I posted on this forum, which has helped me tremendously in the past! I was lucky enough to discover this forum with my 05 OR at around 90K miles. It was lucky for me that the car never developed the dreaded strawberry milkshake and I succesfully completed the RAD bypass surgery in my driveway. Its been at least 6 mos since that bypass and I've driven in hot TX weather, towed a light lawn trailer half way across the country without any TRANS heat problems just utilizing the stock TRANS air cooler up front. BUT, yesterday driving up some 15 plus miles of very steep mountain roads in 80 plus degree temps at 5-6K feet up, the PATHY gave out and went into limp mode. I was focusing on the twisty road and noticed everything bogging down, looked at the dash and it was like a Christmas Tree! Luckily had a place to pull over immediantly and let things cool down at idle, pouring some water all over the stock cooler up front to help out. When I pulled the TRANS dipstick, that sucker was smoking! Turned off ignition, restarted, and all lights went off except the Check Engine. Fine the rest of the day, but mostly was downhill after that. A local Transmission shop suggested that I might just take out the stock cooler up front and replace it with a much beafier unit that would help make up for bypassing the one on the RAD? Does this seem OK? Most people are just adding a second one in front of or behind the current factory one, but if you just ditch that stock one and put in one that handles twice the load of the factory one, won't that be just as efficient?? Any thoughts would be much appreciated! Also, I have about 40K on the current TRANS fluid, considering that it heated to the point of LIMP mode, do I need to replace the fluid as well?? AND, will that Check Engine light cycle off on its own now, or do I need to have that cleared as well??

THANK YOU!

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eieio
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Re: Limp mode after "bypass" surgery

Postby eieio » Mon Jul 27, 2015 12:30 pm

khavel wrote:So its been several months since I posted on this forum, which has helped me tremendously in the past! I was lucky enough to discover this forum with my 05 OR at around 90K miles. It was lucky for me that the car never developed the dreaded strawberry milkshake and I succesfully completed the RAD bypass surgery in my driveway. Its been at least 6 mos since that bypass and I've driven in hot TX weather, towed a light lawn trailer half way across the country without any TRANS heat problems just utilizing the stock TRANS air cooler up front. BUT, yesterday driving up some 15 plus miles of very steep mountain roads in 80 plus degree temps at 5-6K feet up, the PATHY gave out and went into limp mode. I was focusing on the twisty road and noticed everything bogging down, looked at the dash and it was like a Christmas Tree! Luckily had a place to pull over immediantly and let things cool down at idle, pouring some water all over the stock cooler up front to help out. When I pulled the TRANS dipstick, that sucker was smoking! Turned off ignition, restarted, and all lights went off except the Check Engine. Fine the rest of the day, but mostly was downhill after that. A local Transmission shop suggested that I might just take out the stock cooler up front and replace it with a much beafier unit that would help make up for bypassing the one on the RAD? Does this seem OK? Most people are just adding a second one in front of or behind the current factory one, but if you just ditch that stock one and put in one that handles twice the load of the factory one, won't that be just as efficient?? Any thoughts would be much appreciated! Also, I have about 40K on the current TRANS fluid, considering that it heated to the point of LIMP mode, do I need to replace the fluid as well?? AND, will that Check Engine light cycle off on its own now, or do I need to have that cleared as well??

THANK YOU!
any stored codes?
if the problem was indeed an overheated transmission, I'd definitely get fresh fluid in there
if the problem was an overheated transmission due to slow uphill driving, i'd be more tempted to put a new radiator in it (un-bypassed)
external coolers are at their best with good air flow
slow heavy load driving prevents good air flow, no matter how many, or how big they are
adding an additional cooler (one in front of the other) will reduce air flow through both

khavel
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Postby khavel » Mon Jul 27, 2015 4:07 pm

Not sure about the codes since I d have a reader but I'm fairly certain it was a hot TRANS. Everything else was looking good (coolant temps) and it was going just with no power like I was dragging an anchor. When I pull the TRANS dipstick it was smoking hot. My speeds going up the steep grades were around 20-25 mph, is that enough airflow for the cooler up front? I'd rather not pay $500 plus for a new radiator install if I can get away with a large cooler up front ($230 installed). In retrospect I should've been running the AC since that kicks on the condenser fan pulling more air through the cooler. Thoughts on one large cooler vs two stock sized ones together??

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smj999smj
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Postby smj999smj » Mon Jul 27, 2015 4:44 pm

You can get aftermarket radiators for around $75 on Ebay, which is probably what you are going to pay for a good auxiliary cooler. Liquid-to-liquid coolers are far more efficient that air-to-liquid coolers. If it were me, I would keep the factory auxiliary cooler, replace the radiator with an aftermarket unit and service the trans fluid. Buy the parts yourself and you should be able to get the trans replaced for well under $500 unless there are extremely high labor rates where you are. Labor guide time is 3.0 hours.

khavel
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Postby khavel » Mon Jul 27, 2015 6:05 pm

thanks smj! you've helped me in the past. much appreciated. i guess i didn't know that you could get your hands on a decent radiator for the pathfinder for that kind of money, since i've read on here that Nissan charges $600. also didn't know how much labor to install that radiator would be either. any recommendations on radiators? I'm still not excited about a $500 repair especially since I've never had any TRANS heat issues just doing the bypass, but if that gets me piece of mind in hot high load situations, it's worth that, plus I'm not one of the milkshake club having to fork over REAL $$...

Also, if i'm paying to have the radiator replaced, i guess it makes sense to get the water pump replaced while everything is out of the way right??

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smj999smj
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Postby smj999smj » Tue Jul 28, 2015 1:07 pm

Well, the water pump is driven by the timing chain. You could change that if you wanted to, but they really aren't a high failure item. I would just replace the radiator. I purchased a no-name, Chinese-made radiator for $92 about 3-years ago and it's been fine and appeared to be as well made as the original in terms of fit and construction. Most aftermarket radiators, regardless of brand, are made in China, including the popular Spectra Premium brand, which usually sells in the $120~ range. If you are a bit on the picky side, like me, you can get the foam seals from Nissan which don't come with the aftermarket units. They aren't expensive, but you won't notice any difference without them. They may help keep some of the leaves and debris out from between the radiator and condenser cores, though.

khavel
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Re: Limp mode after "bypass" surgery

Postby khavel » Fri Jul 31, 2015 6:55 pm

any stored codes?
if the problem was indeed an overheated transmission, I'd definitely get fresh fluid in there
if the problem was an overheated transmission due to slow uphill driving, i'd be more tempted to put a new radiator in it (un-bypassed)
external coolers are at their best with good air flow
slow heavy load driving prevents good air flow, no matter how many, or how big they are
adding an additional cooler (one in front of the other) will reduce air flow through both[/quote]

I bought a WIFI OBD2 Adapter and an App for the iPhone to pull the codes. All I had in there was a (U1000). And the Check Engine Light was active still since the incident. I was able to clear the code and turn off the light, which was worth my total investment of $26 alone. But I can find much about the code except it's kind of a generic one. Any ideas. Nothing else stored or pending.

khavel
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Postby khavel » Fri Jul 31, 2015 7:29 pm

Ok, some further info on what happened the other day when the Pathfinder went into LIMP mode. When I lost power and looked at the dash, the check engine light was on, the 4wd light was on(but I was in 2wd), the oil light was on, the LCD display that shows if you're in 2wd or 4wd went away completely! The reason I'm mentioning this now is I've loo online for similar symptoms and found a guy that described this exact scenario a few years ago. But the forum didn't have a diagnosis?? Could this have been an electrical issue, not a TRANSMISSION issue?? With no other error codes but that U1000 CAN code, could this just be a basic grounding issue? Any help is appreciated!!


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