Radiator fails and dumps coolant into transmission fluid destroying the transmission on Nissan Pathfinder

Problem Data
Average mileage: 124,456 (143–250,000)
Drive Trains affected: 2WD, 4WD, Automatic Transmission
7 model years affected: 1993, 1995, 2003, 2005, more2006, 2007, 2008
110 people reported this problem
Viewing 1 - 20 of 66 comments
This is happening to thousands of mostly 05 and 06 pathfinders. Nissan denies the problem as it usually occurs after the 80,000 mile warranty period. If your transmission still has bright red transmission fluid get it to a garage quick and request that they add a transmission cooler and eliminate the cooling loop thru the radiator. If your transmission fluid is pink then just go ahead and have the transmission rebuilt and a cooler installed. Nissan will charge you up to 6,000 for this job so go to your local transmission shop instead. Google pathfinder problems and join the list of people ripped off by Nissan, never buy another nissan product and join the class action suit against Nissan. They installed a defective radiator in these cars and refuse to take responsibility for it.
In 2/2007 after driving my 2007 Pathfinder SE Off Road for only 3 miles, it started to slip while shifting and making loud clunking sounds. I pulled off to the side of the road and saw an odd colored liquid leaking from the coolant overflow tank. I left the car and called for a ride home.

A few hours later, I went back to the car with some coolant and water, expecting that there was some sort of coolant leak. Upon opening the radiator cap and the overflow tank, I found a sludge like pudding consistency liquid.

The car was towed to the local repair shop and I was told that there was a leak and the coolant system and the transmission fluid had combined. They said they see this with many Nissan trucks.

I had the radiator replaced and the the transmission flushed several times until there were no remains of the sludge in the transmission. ----Cost $1,300.00

I drove the car for about a month without a problem at all, until while driving up my street the car lost all acceleration and had no forward or reverse gears.

This time it went to a transmission shop. A complete rebuild was required. And, it was also suggested that we add an external transmission cooler. However, I was told the transmission computer was still ok. ----Cost $3,350.00

After receiving the car back, I drove it approx 75 miles and experienced the same loss of acceleration and no forward or reverse. Back the the transmission shop it goes.

The transmission shop takes the entire transmission apart to learn the the transmission computer is bad now, which is located in the transmission. ----Cost $1,200.00

Nissan is aware of the problem - It's a design flaw. The same design is used in other trucks they make.

I'm aware of the "Class action law suit" however, it doesn't help anyone who has a truck with over 100,000 miles, and considering that is when the problem develops, I find Nissan's fix ridiculous.

I have now spent $5,850 to fix a problem that Nissan should have issued a full recall for. I will never ever buy another Nissan again. I've made it a point to let everyone I know to never buy a Nissan product.

It's truly amazing how my local Nissan dealer wanted no part of helping me.
Had to put 3400 dollars in for a rebuilt transmission last year at 88,000 and just learned my radiator is spilling crap into this new one. Just passed my 100,00 mile mark. Single mother that has just recently been laid off.
Coolant mixing into transmission. Dealer asking 6,000 to repair. What a rip OFF!!! I want buy another nissan.
About 5 months ago, my pathfinder transmission started shuddering and slipping, took it to the dealership and of course they didn't have a clue what was wrong. We continued to take it to different dealerships to try and figure out the problem, after no progress I started searching online and found all these websites about the rad leaking into the tranny, well that was the problem and Nissan admitted that it was a"known"defect but since my car was past the mileage, it wasn't covered. So I got stuck with the bill and got it fixed. It's now Oct.9th/2015 and I'm starting to have the same symptoms.. I'm fed up with Nissan, their attempt to resolve the situation was pathetic, since most people who have this defective part, don't notice it until it's past the 80k mile coverage, even if it wasn't you still have to pay the $3,500 co-pay!? I will NEVER buy a Nissan again, they do not care about their customers or the quality of their products. Steer clear,
Had Radiator rupture and mix coolant into transmission, destroying both of course. Noticed the issue when I drove at around 50-80 mph. Experienced hard grinding like vibrations and hesitation when this happened. Drove this way for a weeks then took into a Nissan dealer. Was told they couldn't find the issue. A mechanic rode with me to see if he could experience what I did, but would check again when I rescheduled. Meanwhile during that ride along I mentioned what I suspected it to be because I did search on the internet about the symptoms. This exact same thing is what I read people were having.

Rescheduled the appointment Tuesday of this week and within an hour and half they called to inform me what I told them it could be. Radiator ruptured and leaked into transmission destroying both. $7,600 repair but luckily it was covered 100% because I purchased the 5-yr warranty 2 years ago.
I am still paying for a car that has been sitting in the driveway for over a year.
Break in the radiator dumped coolant into the transmission and ruined it. Required replacement of both radiator and transmission. Also had timing belt on its way out when I got the car to the shop and that also required replacement. Also had a fuel gauge that wasn't working and required replacement for that. Total cost >$4800.00. Radiator/Transmission problem was a few months out of the time for full replacement and it cost me a healthy "deductible" to have it fixed - plus all the other repairs. At the time, there was less than 64000 miles on the car.
Car overheated. That's how I found cross contamination. Waiting to here from nissan for assistance
I have had to have mine rebuilt.
Similar problem to what others have described. Vehicle has 120k miles on it, shudders at around 60-65 mph, and also has trouble shifting from 1st to 2nd when warmed up. Took it to my local mechanic. Radiator coolant is leaking into the transmission. $5k plus to fix. Nissan should definitely do something about this.

Has anyone had experience with re-engineering this so that the problem, once fixed, doesn't recur another time for the exact same reason?
The vehicle has ran hot several times before. The problem was usually fixed by topping off coolant. Recently I noticed a leak in the heater hose assembly. I thought I solved the problem by using a sealant. The sealant lasted approx 5,000-7,000 miles. One day when I got to work smoke was coming from the hood and the heater hose assembly was spewing coolant. Luckily I had a gallon with me and was able to top off the coolant, turn the heat on and make it home. Once again I was able to top off the coolant and drive to Nissan to have the heater hose assembly replaced, which is a $250 part plus labor. While having the repair done the mechanic explained to me that there was transmission fluid in the radiator and coolant in the transmission. As a result the transmission would have to be rebuilt. The Nissan mechanic recommended a new radiator and system flush however a local mechanic I inquired with said he would bypass the current radiator, add a transmission cooler then flush the system. There's not really a way to tell how long it had been this way but the damage resulted in nearly $5,000 in repairs.
Radiator has failed and coolant leaked into transmission @ 105,000 miles. I flushed the bad fluid and replaced adding a anti-slip additive package with seal conditioner to new fluid all seems well. Currently @ 113,600 no slips, kicks, noises or failure.
We've had our Pathfinder since early 2006 and had virtually no problems aside from routine maintenance repairs until Nov 2015 when, on a trip, it felt like it was stuck in a high gear. Ended up being the same cracked radiator problem. Had to replace radiator and transmission, and then repair heat about 2 weeks later (heat stopped working when car was idling--seems to be a connection to transmission issue based on Googling). Now the check engine light is on and the diagnosis is the catalytic converter. Should not be related to the transmission, but makes me wonder. We are over $4k into this series of issues. Bummed that Nissan won't truly own up to the issue. We probably would have considered purchasing another Nissan prior to this series of events.
On the way to a skiing trip, the transmission failed - I went to accelerate on to a highway and it kept slipping. I could get it to run, but at only about 25 mph. We located a dealer close by and they got a loaner for us that was big enough to get all our gear in and we continued our trip, leaving the Pathfinder at the dealer. They called me the next day and said the coolant/transmission fluid had mixed due to a pump failure and both systems would need to be replaced - $6000. No wonder they were generous with the loaner! Nissan would do nothing for us since we were at 106K miles. It was the third failure this dealership had seen.
My pathfinder would not shift into gear while driving. It completely stopped and it would not start. Had it towed to AAMCO trans and they told me that it was the crank sensor, picked up the car a week later, as I was driving it home it started again, would not go into gear and eventually stopped, had it towed again to the shop and they told me it was my transmission..they found radiator water/coolant inside the transmission. They are rebuilding the transmission and are quoting me $4,900.00. I am so upset!!
Had to replace transmission
Foolish radiator design allowed tranny fluid loop through radiator to fail causing radiator fluid to contaminate and destroy tranny. $5,100 to repair instead of $100 to add an external tranny cooler. Stupid design followed by Nissan's refusal to fix the problem or to advise owners out of warranty of the problem years ago.
Nissan frontier 2006, very good truck but noticed coolant missing every week, maybe radiator leak but, couldn't find it. I read 2 weeks ago of this problem and started checking my oil in the Transmission but all clean, I called Nissan suspecting this problem may soon happen since symptoms were there, and last night it happened , got stuck in 2nd gear., their answer is simple and cold : you are on your own we can't do nothing about it !! Why didn't I get a recall like the law states, I serviced my car at Nissan most of the time (brakes ,oil)
Now I understand they wait you pass 100000 miles so they go clean !!
I will NEVER buy or use a Nissan again, after buying 3 cas on the past 10 years.
Cross contamination of ATF and coolant. Radiator is being replaced and system flushed. Seems like a popular nissan issue. I going to purchase a Titan next but have reconsidered.