The Nissan Path

Hey everyone! I just found out the other day my rear heater lines are leaking after taking it to the dealer due to no heat. I thought it was the controller cause I could get heat for a few seconds if I kept switching the settings around, but they told me it was due to low coolant due to the leak. After they told me it'd cost $1200 to fix, I did some searching here to see if there's a cheaper/better way to remedy the problem. I did find one post where it was suggested to just cap off the lines, but they didn't say how to do it. Has anyone done this and if so, how? Did you do the AC lines too? I think I can live w/o the rear heat/ac considering the cost and the fact it'll probably reoccur. TIA!

edit: forgot to mention it's an 05 with 78k miles.

I had my lines, both heater and AC, done on my 2005 (my previous Pathfinder). The core itself was rusted out and I kept smelling coolant. Essentially they have to lift the body off the frame to do this. Was very expensive but fortunately I had an extended warranty from Carmax that paid for it.

My lines started leaking right after I bought my car. I rarely go to the stealership unless I have to and so I found a private shop to do it for about 800$ Since I just got the car I wanted it to work and I had budgeted for some initial work to be done on the car so it wasnt so bad.

An alternate solution some people have done is to just cap off the lines and not have the rear air feature. This will be your cheapest solution.

I have an '05 Pathfinder and I started noticing a coolant smell around the passenger side rear wheel well. I searched several times and even went as far as removing all of the rear interior panels to check the heater core and lines in there for leaks, to no avail. Finally, I found that the aluminum lines had corroded through next to the exhaust above the rear shock mount on the passenger side. After checking on this forum, I saw that this is a common problem where the vehicle is exposed to salt (truck spent first 2 years of its life in Pennsylvania) and is a very expensive repair. I decided to tackle it a different way. the lines in questions are 5/8" O.D. aluminum. After draining the coolant as much as possible, I cut the old lines using a small air powered saw in front of the rear end spring shock structure and then behind it. I was able to get the old lines out and then route standard 5/8" heater hose between the body and suspension hardware and make the connections. I routed and secured the new hose to make sure it would not rub or be pinched and everything seems fine. Kids would not have liked losing the rear heat in the winter.

Glad you found a way to fix this yourself. Welcome to the forum by the way!

racerruss wrote:I have an '05 Pathfinder and I started noticing a coolant smell around the passenger side rear wheel well. I searched several times and even went as far as removing all of the rear interior panels to check the heater core and lines in there for leaks, to no avail. Finally, I found that the aluminum lines had corroded through next to the exhaust above the rear shock mount on the passenger side. After checking on this forum, I saw that this is a common problem where the vehicle is exposed to salt (truck spent first 2 years of its life in Pennsylvania) and is a very expensive repair. I decided to tackle it a different way. the lines in questions are 5/8" O.D. aluminum. After draining the coolant as much as possible, I cut the old lines using a small air powered saw in front of the rear end spring shock structure and then behind it. I was able to get the old lines out and then route standard 5/8" heater hose between the body and suspension hardware and make the connections. I routed and secured the new hose to make sure it would not rub or be pinched and everything seems fine. Kids would not have liked losing the rear heat in the winter.

You should try and post some pictures if you have them or can take them of what you did. I think there might be alot of people who would love to see them.

racerruss wrote:I have an '05 Pathfinder and I started noticing a coolant smell around the passenger side rear wheel well. I searched several times and even went as far as removing all of the rear interior panels to check the heater core and lines in there for leaks, to no avail. Finally, I found that the aluminum lines had corroded through next to the exhaust above the rear shock mount on the passenger side. After checking on this forum, I saw that this is a common problem where the vehicle is exposed to salt (truck spent first 2 years of its life in Pennsylvania) and is a very expensive repair. I decided to tackle it a different way. the lines in questions are 5/8" O.D. aluminum. After draining the coolant as much as possible, I cut the old lines using a small air powered saw in front of the rear end spring shock structure and then behind it. I was able to get the old lines out and then route standard 5/8" heater hose between the body and suspension hardware and make the connections. I routed and secured the new hose to make sure it would not rub or be pinched and everything seems fine. Kids would not have liked losing the rear heat in the winter.

Smart fix. Wonder if Nissan has thought about this but enjoys their $1200 repairs too much to do it this way.

had the same problem, where the lines corroded. did the same procedure as above, cut the lines and replace it with rubber tubes. It wasnt easy, but it works. I will post up some pic

I just noticed this morning I'm not getting any heat out of the rear. I may be the first with an '08 and this problem...but I admit I don't wash it enough in the winter. Or summer

Hi all, I have the same problem here in the UK (where they see fit to use salt EVERYWHERE!). Going to cut out the corroded section of pipes under the rear wheel arch and replace with hydraulic grade rubber hose with clips. Will keep you updated!

Also, thanks for starting this thread. Here in the UK, Nissan want £2,000 to replace the tubing which as I write this is around $3,114!!!! If it wasn't for this thread I may well have had a nervous break down :/

Well I took a look under mine and the lines look fine and my coolant level appears good. Not totally clear how this works...does coolant run to the rear unit all the time or only when you're calling for heat in the rear? I assume if the lines are bad it will leak all the time and I should be low on coolant? I'm just not getting any heat from the rear vents. It's not really a big deal and if anything the front seem to work better when I'm not using the rear. Considering how goofy my front system is at time (temp fluctuates all over the place) I wonder if this isn't related to the same issue.

Having read this thread I wondered if anyone has thought about using PEX pipe front to back, It is very strong and as plastic not a corrosion problem. If you can use rubber at each end to reconnect to factory. It is not a high pressure system - compared to domestic water.

I live in the snow belt so always interested in these issues.

for the UK - that is cross bonded poly pipe like you use for domestic heating - has a red stripe.

Well, I didn't get around to doing the job today but will tackle it tomorrow instead. As for PE-X pipe (we call it that in UK too) I think that's a fine idea! I did wonder about it myself, perhaps using push-fit connectors? The aluminium pipes are 16mm I think, so maybe connecting to 15mm could pose a problem? Any thoughts??

skinny2 wrote:Well I took a look under mine and the lines look fine and my coolant level appears good. Not totally clear how this works...does coolant run to the rear unit all the time or only when you're calling for heat in the rear? I assume if the lines are bad it will leak all the time and I should be low on coolant? I'm just not getting any heat from the rear vents. It's not really a big deal and if anything the front seem to work better when I'm not using the rear. Considering how goofy my front system is at time (temp fluctuates all over the place) I wonder if this isn't related to the same issue.

I think the coolant runs around the whole system all the time, regardless of whether it's being called for by rear climate controls as mine is leaking from those damn corroded pipes even with all heating controls off! Perhaps your problem is with the rear heat exchange..maybe clogged up with sludge as seems another common Pathy issue!

Good news and bad news. I cut the pipes and fitted 6 inch long pieces of hydraulic grade hose without too much fuss...then noticed a second leak further up the chassis at the next rubber grommit/clip thing. What makes this one really annoying is that you can't get to the damn thing. Next step now is to find a way of capping the pipes off just before they disappear up into the frame and do away with rear heat altogether. Will this stop all heaters working though as the coolant will no longer flow in a circuit?