Radiator cracked on the cummins

[The motor guy]

I noticed the plastic sides of the radiator are cracked. The driver side is the worst and the passenger side is following behind. I think the frame flexing causes the plastic to crack near the mounts. It's always something, hopefully I can get a new one in before it goes completely.

 

[The motor guy]

Opinions?

 

[928]

A quick look shows radiators are pretty cheap- the mopar one looks like it's factory replacement

https://www.rockauto.com/en/catalog/dodge,2007,ram+2500+pickup,5.9l+l6+diesel+turbocharged,1433802,cooling+system,radiator,2172

 

[DoubleWasp]

Doubt it. IIRC, you have a fairly modern Cummins truck. Radiator is rubber mounted, and those rubber mounts have way more than enough flex in them that even if the two sides of the truck were flexing a full 1/2" that wouldn't happen. This is impossible, of course, because other things would simply break if that happened. Forget cracks.

Far more likely that age and heat have simply gotten the better of the plastic. This is the fate of all plastic/aluminum radiators.

 

[Colt45ws]

Originally Posted by DoubleWasp
Doubt it. IIRC, you have a fairly modern Cummins truck. Radiator is rubber mounted, and those rubber mounts have way more than enough flex in them that even if the two sides of the truck were flexing a full 1/2" that wouldn't happen. This is impossible, of course, because other things would simply break if that happened. Forget cracks.

Far more likely that age and heat have simply gotten the better of the plastic. This is the fate of all plastic/aluminum radiators.


I wouldnt discount it flexing of the vehicle. If one does off roading that causes one side or the other to become heavily loaded, the frame and body does flex.

 

[berniedd]

Plastic aging. My Honda plastic radiator developed a 4-inch horizontal crack at the top, at its 11th year, just like your Cummins.

 

[DoubleWasp]

Originally Posted by Colt45ws

I wouldnt discount it flexing of the vehicle. If one does off roading that causes one side or the other to become heavily loaded, the frame and body does flex.


Agreed, But enough to drive the rubber mounts on both sides up against their solid external stop and crack the tanks? I know these trucks well. I have two of them, and have changed the radiators in both. The only way the radiator mounts reach a mechanical limit beyond the rubber would be for one side of the radiator support to be at least a few inches out of whack from the other side. His support would fold up and stay that way if that ever happened.

The lower mount is a rubber nub-in-pocket design. Top is similar. With the top mounts unbolted, these mounts allow enough flex that you can pull one side of the radiator up by 4-5 inches with the other side flexing inside of the pocket. Even if the radiator support started turning into a rhombus, the mounts are going to keep allowing for angle well past the point that the radiator support develops permanent damage and sticks the hood closed forever.

 

[Lubener]

Don't overlook an engine mount causing a tug on the hoses. It happened to me once.

 

[SwampSurvivor]

Radiators are pretty resilient. My Cherokee was totaled in a head on collision at 11000 miles. It had the factory radiator up until 202000 miles. When I pulled it out, it was actually bent from the impact 15 years prior. I also had a lot of offroad miles on it. Unibody flex didn't get it, corrosion did.

Plastic endcaps are very well known to crack and leak

 

[Chris142]

Its 11 yrs old! Most didn't last that long. Its pretty easy to replace. Except for 1 thing. The radiator flares out at the bottom so you must remove the charge air cooler as its pipes are in the way. Be carefully with the ac condenser and lines.I find it easier to suck the ac dry and remove the condenser.

There is a bleeder on the passenger side of the engine that must be opened when you refill the cooling system.

 

[ECUpirate]

Same thing happens to my Silverado about every 50k miles with the AC Delco replacements, always cracking on the driver's side. I do a fair amount of off-roading and I'm convinced it's attributed to flex. A mechanic told me the rubber mounts tend to get stiff over time and suggested I replace them, which I will when I replace this latest one that has just started to leak. Just something to consider.

 

[sprite1741]

Plastic cracks with age. I get 12 years with a plastic tank and they crack or leak where the tubes connect. Maintenance item, get a lifetime warranty if you plan on keeping it.

 

[ofelas]

Get an all aluminum Mishimoto & install it.

 

[bullwinkle]

I've been holding my breath every time I open the hood on my '06-plastic radiator AND plastic intercooler! Cheap, cheap, cheap! I've JB welded cracked radiator tanks in the past, but it didn't seem to last very long.

 

[bdcardinal]

FWIW the Ford 6.4L diesel radiators leak all the time. Supposedly the cause is the body mounts causing flex which then causes the radiator to leak.

 

[The motor guy]

Originally Posted by bdcardinal
FWIW the Ford 6.4L diesel radiators leak all the time. Supposedly the cause is the body mounts causing flex which then causes the radiator to leak.



Yeah the body mounts only last a couple years. Bill Hewitt on powerstrikw help has a video about that.

 

[Colt45ws]

Originally Posted by motor_oil_madman
Originally Posted by bdcardinal
FWIW the Ford 6.4L diesel radiators leak all the time. Supposedly the cause is the body mounts causing flex which then causes the radiator to leak.



Yeah the body mounts only last a couple years. Bill Hewitt on powerstrikw help has a video about that.

 

[The motor guy]

I don't think that's an issue on the dodges though.

 

[DoubleWasp]

Originally Posted by Chris142
Its 11 yrs old! Most didn't last that long. Its pretty easy to replace. Except for 1 thing. The radiator flares out at the bottom so you must remove the charge air cooler as its pipes are in the way. Be carefully with the ac condenser and lines.I find it easier to suck the ac dry and remove the condenser.

There is a bleeder on the passenger side of the engine that must be opened when you refill the cooling system.



I've had good luck doing the fold-over of the AC condenser to the passenger side, with a towel draped over that side. CAC definitely has to come out, though.