[jrmutley]

Hey everyone. This is my first real post and pretty much why I joined. I'm hoping for some good advice as I keep my '07 Frontier for at least a few more years (cross fingers). Anyway, here is my issue.

Recently I started noticing the scent of anti-freeze. After checking things out, I discovered a leak around one of the heater core hoses (see pics). I don't have anything leaking in the interior of the truck. It appears to just be from that hose. So, a couple of questions:

1) Is it possible just flushing the heater core could fix my problem?

2) What exactly is that plastic connector that the rubber line is going into and the metal pipe going off to the right?

3) if that plastic part is some sort of valve, could it be blocked or malfunctioning and need to be replaced (instead of an issue with the heater core)?

Thanks!

 

[10935]

You need the whole aluminum tube that wraps around the back of the motor on the firewall... I had to replace it before because the plastic got brittle and snapped when I bumped it. Was about 80 bucks for the whole thing at the dealer, took 10 min to install with hand tools.

 

[jrmutley]

Are you saying that is what is malfunctioning and not the heater core (a blockage there) itself? If so, that would be a huge relief. That aluminum tube attaches to the firewall by just a couple of bolts. Looks pretty easy. What is the purpose of that whole piece?

 

[10935]

Looks like a leaking plastic fitting to me. Does your heat work?

The tube carries coolant to your heater core, so you have heat. lol

 

[jrmutley]

I get that. I mean, why does it go through the plastic piece instead of just right into tubing that connects to the heater core? Does the plastic piece have some sort of other purpose other than just complicating things? LOL.

 

[10935]

My guess is so after 6 years or so Nissan can collect 80 dollars on a replacement. No idea really, planned obsolescence?

Call your dealer soon, I got lucky as someone had ordered the part but never picked it up so it was in stock. But the guy at the counter told me if he'd need to order it, could be more than a week.

 

[jrmutley]

Will do. I'm just relieved that it probably isn't the heater core. When I call the dealer, what should I call the part?

Thanks for your replies!

 

[Clint]

I replaced that on my pathfinder when I like the other poster bumped into it. Fortunately my dealer keeps them in stock. None of my Frontiers had them fail.
Do it now while it's not a completely failed part.

Clint

 

[shift_RUSH]

Not sure what yr your Frontier is, but:
Are you running the original stock radiator...and IFF so, are you aware of the possible transmission-fluid/coolant cross-contamination issues associated w/ '05-'10? AKA SMOD?

Edit: I see you have an '07 Frontier...so, if you're auto trans then you'll want to look into this/SMOD.

 

[smj999smj]

They simply refer to it as a heater hose assy. It's a fairly common failure. The good thing about plastic coolant fittings is that they don't corrode like aluminum fittings; the bad thing is that over time, they get brittle and break. The only reason I could see that they use the plastic fitting is that it is a really tight bend from the heater core fitting at the firewall to the pipe on the firewall, so it would be easier to make by using a plastic fitting. At least they are not too expensive on the Frontier; the ones on the Pathfinders w/ rear heat are around $175. As far as flushing the coolant system, there is very little need to do so. Today's coolants are long-life, so usually a drain and fill at the intervals recommended by Nissan serve well enough. If you have a 2007, you're still using Nissan green coolant, so the first interval would be at 90,000 miles and every 60,000 miles, afterwards, if I'm not mistaken (you can check your owner's manual to be sure). If you use concentrated anti-freeze, mix 50/50 with distilled water (not tap water). As mentioned, if you still have the original radiator and have an automatic transmission, it would be a good time to replace the radiator due to the trans cooler issues with them.

 

[jrmutley]

Not sure what yr your Frontier is, but:
Are you running the original stock radiator...and IFF so, are you aware of the possible transmission-fluid/coolant cross-contamination issues associated w/ '05-'10? AKA SMOD?

Edit: I see you have an '07 Frontier...so, if you're auto trans then you'll want to look into this/SMOD.

Shortly after I bought my '07 used, I read about that issue. I don't know if the original owner had already taken care of it or if I just got lucky. But, mine has never shown any signs of cross-contamination. (Cross fingers, knock on wood)

 

[shift_RUSH]

Replacing your original radiator is a heckuva lot cheaper than replacing your automatic transmission...AND your radiator if SMOD occurs. Keep knocking on that wood...or be proactive.
$0.02

 

[smj999smj]

Check the top radiator tank for a Calsonic sticker. If it has any of these P/N's, the radiator is original and you should bypass the cooler or replace the radiator (if there is no sticker, it is likely aftermarket): 21460-EA200, -EA215 or -EA265.

 

[jrmutley]

Check the top radiator tank for a Calsonic sticker. If it has any of these P/N's, the radiator is original and you should bypass the cooler or replace the radiator (if there is no sticker, it is likely aftermarket): 21460-EA200, -EA215 or -EA265.

Ugh...I just checked. It is a 21460-EA215. Guess I should consider a replacement. :frown:

Update on my original issue. I called a Nissan dealership that is near my work on Tuesday. They had one in stock...$57 plus tax! That made me happy. Swapped it out that night when I got home. Took about 30 minutes or so. Very easy.

Even though I couldn't see a crack on the old one, that must have been it. No more leaks! Thanks again for the replies and great advice.

 

[Clint]

Good to know you fixed it and didn't leave us hanging. What did you think of those pre-loaded hose clamps, squeeze and they snap in place.
Don't hesitate on the radiator, my Pathfinder was good one day and trans trashed the next day.

Clint