I by-passed my in radiator tranny cooler

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

Moderator: volvite

Find_The_Path
Posts: 19
Joined: Wed Jun 04, 2014 9:05 am
Location: Southwest Ohio

Postby Find_The_Path » Wed Jun 04, 2014 8:45 pm

Sorry to kick a dead horse.
Bought a Pathy yesterday.
'08 4X4 94K miles S No bypass
Getting ready to do the bypass, driving my old car until I do.
To confirm, 3/8" or 5/16" barb?
Same for the vacuum caps, 3/8" or 5/16"?
Assuming clamps are universal as you can just tighten them more or less.
Also, there has been some mention of flushing the internals of the radiator where the tranny fluid had previously ran with an $11 kit from Nissan. Has anyone done/recommend that?
I'm assuming I can't damage the hoses pinching them off. May use vice grips and towels?
Or would it be better to just replace the two broken lines with one new piece of transmission line? If going that route, what size is the transmission line?
Been reading the boards for like 6 hours total now.. come to find out I just need to do like 15 minutes of work.. ha ha ha..
Thank you for all the help!!!!
Glad to finally be back in a 4x4 after having a Civic for the past 8 years!


User avatar
smj999smj
Site Admin
Posts: 5759
Joined: Sun Jan 22, 2012 11:13 pm
Location: Prospect, VA

Postby smj999smj » Wed Jun 04, 2014 11:11 pm

The cooler lines are 10MM, so 3/8" caps and 3/8" ID transmission cooler hose is used. I don't believe you'll need to purchase a barbed fitting as there is already one installed on 08 models (refer part code 21533X on the part diagram linked below). You can use worm clamps, but I prefer to use the Nissan constant tension clamps, P/N 01558-00451. If you want to clean out the cooler, you can use Kooler Cleaner which comes in a can and available at many auto parts stores. I think using a little compressed air and brake cleaner would work just as well.

Find_The_Path
Posts: 19
Joined: Wed Jun 04, 2014 9:05 am
Location: Southwest Ohio

Postby Find_The_Path » Thu Jun 05, 2014 4:47 am

I'm confused, isn't that barb still needed? I'm assuming the two lines shown in the linked diagram (Image #2) at the bottom left of the screen are what need to be tied together, 21623 and 21621. Or am I completely reading the diagram wrong? I plan on taking the sheild off the car tonight and tracking the lines myself to better understand the setup. Seem pretty straight forward.
Are the parts purchased at Nissan, and online Nissan parts dealer or just a local auto parts store? I prefer Smyth Automotive in Ohio.
Thanks!

http://www.courtesyparts.com/pathfinder ... _6897.html

User avatar
smj999smj
Site Admin
Posts: 5759
Joined: Sun Jan 22, 2012 11:13 pm
Location: Prospect, VA

Postby smj999smj » Thu Jun 05, 2014 11:46 am

Keep in mind that 05-07 models are different than 2008. In 2008, they moved the auxiliary trans cooler from the right to the left side. IIRC, on the 08 model, the right side cooler hose goes from the right cooler trans line up to the auxiliary cooler. The other hose from the auxiliary cooler runs to a barbed fitting at the left side of the radiator, which connects it to a hose that goes to the left fitting on the radiator. The right side fitting has a hose that connects it to the left trans cooler line. So, the flow is from the trans, to the auxiliary cooler to the radiator and back to the trans.
All you need to do, IIRC, is remove the cooler hose between the barbed fitting and left radiator cooler fitting and the hose between the right radiator fitting and the metal trans line. Cap off the two radiator cooler fittings (clean out the cooler first, if you want). Run a new piece of 3/8" ID trans cooler hose between barbed fitting and the left trans cooler line. You should lose any noticeable amount of fluid, but check the ATF level when done just to be sure.
As far as parts, you can get them at the local auto parts store. I got my trans cooler hose off of Ebay. I purchased 6 ft. of it because I have two that I'll have to do soon. You'll probably need about 2 ft. of cooler hose, but I'd rather have a little extra. If you want the Nissan constant tension clamps, you can get them online or from Ebay or any Nissan dealer. If you have a nearby Nissan dealer, it may be cheaper from them due to shipping costs.

Find_The_Path
Posts: 19
Joined: Wed Jun 04, 2014 9:05 am
Location: Southwest Ohio

Postby Find_The_Path » Thu Jun 05, 2014 1:39 pm

Excellent, thanks for the information. I drew a picture from what I have read, and will upload it. I am assumig I will have to put it on Photobucket or something first, I can't just insert it. I am going to take the shield off tonight and confirm the routing tonight after softball to confirm the diagram and my action plan. I will take a few pictures.
I have already ordered two hose clamps and the double ended barb from Nissan today. $12 total. Guess I didn't really need the barb, but if it is nicer to have, I will use that one instead. I am guessing I can just buy the trans. cooler hose at the local auto parts store. I have a Smyth, O'riley, AutoZone and KOI within shouting distance of each other. Figure one will have it. Smyth is my usual go to. Figure they will have the vacuum caps too.
I am planning on keeping the diagram and creating a clean writeup on a new thread after the mod for those with '08-'10 (or '12 if they want to do it) to see. Considering adding another cooler in the future, or potientally replacing the stock Auxiliary cooler with a bigger one.
The only thing I am towing is the (skinny) wife unit and two vomit and poop machines so I am guessing I do not have to worry about over heating the tranny.
Thanks for all the help!

User avatar
smj999smj
Site Admin
Posts: 5759
Joined: Sun Jan 22, 2012 11:13 pm
Location: Prospect, VA

Postby smj999smj » Sat Jun 07, 2014 5:16 am

A bigger or second auxiliary cooler isn't necessary. Automatic trans fluid should normally run around 175-210 degrees F. Those that have bypassed and measured the fluid temps usually report around 150-175 degrees F. For those that tow anything significant or live in areas where they experience extreme cold, I recommend the replace the radiator rather than bypass. The radiator's integral cooler can either cool or warm the fluid depending on the temperature of the ATF entering it.

Find_The_Path
Posts: 19
Joined: Wed Jun 04, 2014 9:05 am
Location: Southwest Ohio

Postby Find_The_Path » Wed Jun 11, 2014 4:33 am

Did the bypass Sunday, along with front and read diff fluid drain and fill, cabin air filter, engine air filter,

Bought spark plugs too, but didn't realize it was such a job. Getting into that, brake check, and transmission flush and fill (Dealership) soon. I've heard you shouldn't flush and fill at 95K if it's never been done before, but I'm pretty sure that's just from the old days. I can't believe new transmission fluid would ever be a bad thing. I guess we'll see.

Bypass was so simple. I am planning on creating a quick writeup on a new thread in a few weeks. (after vacation). I drew a diagram and took pics.

Moral of the story is 3' of 5/16" transmission cooler hose from the local parts store. bypass radiator from barb between radiator and aux cooler, and connect to metal line from transmission to radiator.

Optional 5/16" vacuum caps and hose clamps (which I did) to seal off radiator.

3/8" was way too big, a lesson I learned the hard way.

Not going to add another cooler.

Thanks for all the advice!

User avatar
smj999smj
Site Admin
Posts: 5759
Joined: Sun Jan 22, 2012 11:13 pm
Location: Prospect, VA

Postby smj999smj » Wed Jun 11, 2014 5:39 am

I wouldn't flush the trans; just do a drain and fill. I usually get a 1-gallon jug of Valvoline Maxlife ATF which works out perfect.

craig1555
Posts: 1
Joined: Mon Aug 25, 2014 2:30 pm

Am I Missing Something

Postby craig1555 » Mon Aug 25, 2014 2:38 pm

I recently purchased an 08. Am I correct that in order to perform the bypass I connect to two lines from the bottom of the radiator together?I
I feel like I'm missing something but after reading everything I can find it seems this is all there is to it. Thanks for your time.

PELLS
Posts: 2
Joined: Tue Aug 26, 2014 12:12 pm
Location: NEW JERSEY

Fried CONTROL MODULE

Postby PELLS » Tue Aug 26, 2014 2:56 pm

I have a 2005 and had just a few instances where my wife thought the truck shifted a little hard in the past two months. Then a couple days ago it just woudldn't crank. traced a blown fuse to the tcm. after dropping the pan and valve body I noticed a lot of sediment on top of the tcm (but no fluid contamination or no contamination in the pan. Fluid was slighty burnt smelling and very dark. Since the truck was used don't know if it had a coolant issue. Does anyone know where to buy a TCM replacement. Thanks for any help Chris

User avatar
eieio
Sponsored Member
Posts: 1830
Joined: Fri Jul 17, 2009 6:42 am
Location: Prescott, Az.

Re: Fried CONTROL MODULE

Postby eieio » Tue Aug 26, 2014 3:36 pm

PELLS wrote:I have a 2005 and had just a few instances where my wife thought the truck shifted a little hard in the past two months. Then a couple days ago it just woudldn't crank. traced a blown fuse to the tcm. after dropping the pan and valve body I noticed a lot of sediment on top of the tcm (but no fluid contamination or no contamination in the pan. Fluid was slighty burnt smelling and very dark. Since the truck was used don't know if it had a coolant issue. Does anyone know where to buy a TCM replacement. Thanks for any help Chris
did you replace the fuse and test drive?
or did you go straight to the valve body for inspection?

Find_The_Path
Posts: 19
Joined: Wed Jun 04, 2014 9:05 am
Location: Southwest Ohio

Postby Find_The_Path » Fri Aug 29, 2014 11:55 am

@Craig1555
Yes, it theory you can do that, however, you then have multiple barbs from your auxillary cooler to your transmission, meaning more of a chance for a leak. Not to mention, my lines were not long enough to do the bypass and be comfortable with it not leaking. Waht I did is below, cost me less than $10 and I've had no issues since.

You will end up with two short pieces of hose that you replaced with the new hose. Use some zip ties to keep the line from moving, and make it a clean installation (I drilled a few holes through the plastic to get the zip ties through).

3' of 5/16" transmission cooler hose from the local parts store. bypass radiator from barb between radiator and aux cooler, and connect to metal line from transmission to radiator.

Optional 5/16" vacuum caps and hose clamps (which I did) to seal off radiator.

PELLS
Posts: 2
Joined: Tue Aug 26, 2014 12:12 pm
Location: NEW JERSEY

tcm u100 code

Postby PELLS » Sun Aug 31, 2014 6:12 am

eieio -- I did try and replace the fuse but it popped instantly. now I have replaced the valve body and tcm. the truck starts but still has u1000 code and service engine and 4wd lights on instrument panel. also shifts hard between 2nd and 3rd unless on gas hard

dman928
Posts: 2
Joined: Mon Sep 08, 2014 11:58 am

Postby dman928 » Thu Sep 11, 2014 8:32 am

I did this to my 2005 yesterday. I skipped the barb entirely, and just routed the hose that is on the drivers side radiator directly into the transmission near the oil filter. I then connected the long hose that I just disconnected from the trans near the oil filter to the other end of the radiator. Seals up the radiator, and bypasses the issue. No barbs or vacuum caps necessary.

It's pretty straightforward when you look at the hoses.

Completely free and takes 5 minutes. I did add another hose clamp, as the nissan ones were not doing the job to my satisfaction.

Cheers
Dave

User avatar
porksoda
Posts: 204
Joined: Mon Mar 31, 2014 9:57 pm
Location: Clovis,NM

Postby porksoda » Wed Jul 08, 2015 9:46 pm

I did this a long time ago but I'll add how I did mine.

Hard to explain without pointing it out to you but I just swapped these hoses so the tranny hose just loops back into the tranny. The radiator hose just stays looped in the radiator.

Good thing about doing this is you dont have to buy anything or cut anything.

Image

Image


Return to “R51 Engine, Driveline and Powertrain”

cron