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GDI's 3row is in the dumpster....Modine's in the XJ

XJEEPER

NAXJA Member # 13
NAXJA Member
Location
Wasatch Range
So I've been fighting this cooling problem since April, had to run the heater over Soldier Summit to keep the temps below 230 on my way home from Moab and it's not gotten better with summer in full swing. I changed out the T-stat with a Mopar unit but it still got hot with normal driving so I decided to pull the radiator and get it tanked. Thinking back, my Jeep was running hotter than normal for about a year, but it's fine in the Utah winter with temps averaging about 40 degrees.

I could see an awful lot of buildup on the tubes of my 3row GDI when I pulled it out, hoping that I was looking at a $30 cleaning job and not a new unit........but it couldn't be salvaged, the core was toast. 9.5 years on the factory 1-row radiator , 5.5 years on a 3-row GDI.....which received regular coolant changes and flushing.

I decided to pursue the GDI "Unlimited Lifetime Warranty" through Duracore Radiators of Connecticut......only to discover that the "unlimited" part is very subjective. They only warranty against buildup in the core tubes if you take it to a shop and have it annually serviced, as well as save all receipts and can also prove that there is no stray electrical current passing through the core, and can also prove without a doubt that Bigfoot really exists............so I politely told them thanks for the warm fuzzy warranty, and bought a Modine from a local shop to replace the junk GDI.

As others have discovered, the 2 row Modine has larger tubes which are less prone to plugging over time, as well a surface area that is plenty adequate to keep my 190K mile, tired out, 89 4.0 cool. I made some short pulls uphill, followed by stoplight idleing , all with the AC blasting on High......and the best I could do was get it up to 200-ish, not bad for a 94 degree day. On the freeway, the temps are spot on 195.


Now to figure out how to get 40 extra HP out of my old motor for $158.00...............
 
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My dad lives in Salt Lake, and has a '00 XJ, he used tap water to fill the radiator, and within two months it was plugged with hard water deposits. So after replacing the radiator and all the hoses, flushing the system, he now uses bottled water to fill it up. Point being, your GDI could have been plugged up that way, so be careful with the Modine. Although it has larger pipes, the hard water there can still plug it up. BTW, the Modine is a much better unit. I've had mine for two years, and no worries!
 
New coolant and distilled water, I'm just suprised that auto parts stores don't carry distilled water alonside it. Just means we have to pick it up at the supermarket....The only thing I used tap water for on the vehicles is when I use the 7 hour flush.
 
GDI is a piece of junk. I went CSF from Dirk @ dpgoffroad. I took my jeep to the trail called John Bull trail very difficulty. This CSF really outcooled!

Modine has 2 tubes. Itself the tube has 1/2" wide compare to CSF has 3 rows with 1/2" wide tube. I mean total of the tubes Modine 1" vs CSF 1-1/2".
 
logdog said:
My dad lives in Salt Lake, and has a '00 XJ, he used tap water to fill the radiator, and within two months it was plugged with hard water deposits. So after replacing the radiator and all the hoses, flushing the system, he now uses bottled water to fill it up. Point being, your GDI could have been plugged up that way, so be careful with the Modine. Although it has larger pipes, the hard water there can still plug it up. BTW, the Modine is a much better unit. I've had mine for two years, and no worries!

I run a water softener here, but I only use the recommended distilled water in my radiator.
 
I put a two row closed radiator from Performance
Radiator in my 88 Comanche. Idling in traffic at 90 degrees, it never gets warmer than 195. Works better than the 3 row open GDI with flowkooler pump in my 90 XJ.

Fred
 
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