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Need new radiator

Joey D said:
He said 2 row 1in tubes. I asked why not a 3 or a 4 and he said it's not needed on there radiator. I want to think he's right but then again.
Click to expand...

That's the same as the stock unit, isn't it? I have no reason to suspect the radiator I pulled out of my truck wasn't the original. If so, 10 years and 136,000 miles isn't a bad life span for $160. Sure the Griffin would be pretty and all, but is it worth it? The cooling would be the same, other than the little bit of additional you'd get from the aluminum end caps.

Now if you took a plasma cutter to open up the front of the truck and had Griffin build a wider radiator, that would be something. ...but I suspect fitting it in would be a problem.
 
Acesneights1 said:
yep. If I had to buy another one I think I would take a crap shoot on it.
Click to expand...

The factory rad is certainly inadequate. I toyed with buying this one too, but after reading about radiators for a few hours, I just went with the aluminum one.

Brass has a higher heat transfer ability, but the aluminum rads have a more efficient design with the wide, flat tubes. Brass can't be drawn into the wide, flat tubes like aluminum, so it takes more rows to do the same job. The general consensus everywhere I read was that it was about a wash.
 
The summit one has more core AFAIK. I still think relocting the a/c condensor would do more than anything. Every 6.5 owner I have talked to that doesn't have A/C in thier trucks has never had any sort of overheating problem. Who knows. If my Tahoe doesn't sell I may still try it. I wanted to use a MACK condensor(you Mack boys, I'm talking mid to late 80s one that mounted y the bumper) with electric cooling fans on it.
 
Griffin makes a very good radiator.

The two 1 inch rows of tubes is a great core. The old school in "Copper Brass" was a 4 row. Now these 4 rows of tubes are small tubes and if you add it all up and then look at the total surface area that the coolant has to contact, the 2 row Griffin is plenty.

Once the thickness starts to get beyond a certain point, the airflow is reduced and so goes the ability to reject heat.

A fresh Visteon Radiator (Factory replacement) will handle the job very well.

The issue is this. The radiator must be clean and free of sludge inside and also the air flow passages must be clean.

Not only the radiator but the Condenser has to pass air freely.

It takes very little crud in the airflow path to drastically reduce the cooling ability.

The fans on these rigs are adequate as long as the clutch works properly.

The lower engagement clutches by Kennedy and a few others helps a bunch too.

A fresh factory radaitor and new clutch with clean coolant and good airflow will cool these things fine.

Now

The water in a lot of localities has a Buttload of nasty minerals and other stuff that really does hamper the cooling system. (Builds up insulating deposits inside the tubes)

We buy the Glycol at the store and mix it with tap water 50/50 and off we go fat and happy.

A couple years down the road the old cooling system is starting to suffer the effects of whatever was in the water we used.

LOOK at your toilet to tell the story.

If the old camode has a nasty rig at the water line in the pot you have lots of minerals in the water.

These minerals can be calicium, iron and a host of other items that in and of itself wont hurt things but they form a coating in the tubes of your radiator that bakes on and effectively insulates the system.

The coolant moves through the tubes fairly fast as does the air through the fins.
If the heat can't transfer from the coolant to the aluminum and then on into the airstream, the system is worthless.

A system that has a lot of miles on it will generally be OK during the winter but, as summer temps start to rise so does the engine operating temperature.

Once the fan finally does come on and run full on (80% hub speed) the temp drops off fairly well but then creeps back up again.

A diesel generates a lot of heat and must have a cooling system that is in top shape to handle it.

The size restrictions in the chassis makes it imperative that the system is in very good shape.

Forget about all the tweeky trick and otherwise cool and expensive gadgets out there.

A factory sized radiator with a factory fan and a clutch that works right will keep it cool.

Just been through all this stuff recently and the cost for the Custom radiator is not worth it.

The custom radiator will do little better unless the fan can pull huge amounts of air through the system.

The fan clutch is the most overlooked item in the system.

"Looks under the hood" Yup its there and turns ok and is not making noise or leaking"

This is not the measure of whether the thing is in good shape.

The fan clutch has a few very important parts that have to work right in order for the clutch to be any good.

The clutch is sort of like a little torque converter (sort of)
There is a sylicone fluid inside that is directed into or kept from a driving assembly.
When the bimetal spring on the front senses heat it moves and this in turn opens the valve inside and allows fluid to pass into the drive unit. The friction of the fluid between the halves of the unit cause the driven hub to turn at a higher speed (clutch engaged)

The fluid does wear out over time from heat and possibly contaminants from internal wear.

The seal behind the "bimetal spring" leaks with age and allows fluid to seep out.
This attrracts dirt and will adversely effect the springs function..


This is a complex system and must all work in concert with the other parts of the cooling system to keep the engine cool.

Sure, a bigger radaitor my help some when the fan is not doing its job or a set of helper fans out front might bandaid things a bit when the radaitor is getting to the end of its lifespan.

Bottom line is simple

When all the parts are to spec and working right, this sytem works.

Just a note **** the Griffin radiator with the welded aluminum tanks will give little more if any real cooling effect. The advantage is simple, the aluminum tanks dont have the hose connections snap off and the rubber seal thats not there does not leak.

I had thought about the Griffin myself. The cost $500+++
A Visteon factory type, $235 my cost.
Hmmmmm no probelm deciding here. The original went 200K.

Just get the OEM unit and be happy.

My 94 Burb had 270k on the original radiator and the top hose bib broke.
Always ran cool even in Summer.

Now if you buy a "OEM Type" be sure you get a unit that has the aluminum brazed core and NOT one that has the tubes set with epoxy.

Many of the cheap overseas items have the tubes epoxied in and when the crack, they leak, GAME OVER

The Visteon radiators are OEM quality (Mexico) and are aluminum brazed cores.


MGW
 
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I did all that. Mine still overheated towing. A few things not mentioned. All of MGWs advice is good and for a stock 6.5 will work just fine however once you start running chips, more boost etc that is where the problems arise. I did the Heath Cooling upgrade and replaced my Rad with a brand new one(A good one). It actually was doing good till I put the turbo master on and brought the boost to a respectable level(12-14). even with the chip I didn't really have a problem until the TM but I don't think (and Heath always says this too) that I was getting the full effect of the chip with the factory waste gate system. So that brings us back to how do you get this thing cool when it's not stock, towing. That my freinds....is the right question...(i robot)
Would an intercooler have solved my problem ? Would an ATT solved it ? Would removing the A/c condensor solved ? Let's ask Mr. Owl....crunch crunch the world may never know...
:)
For now I solved it by buying a Cummins. Now if only I could put a 4l80e in a dodge. Now that would be something.

I have long stood my ground that at highway speed the air flow should be more than an engine fan can produce rendering it un nessicary. The fact that Heat/Kennedy/whatever fans are kickin in at 70 mph to help cool means it's pulling the air though because it can't get though on it's own cause GM stacked way too much sheeettttt in front of the rad. I would bet the farm that If I yanked my a/c condensor and went for a tow it would be fine. Course fat boy likes his a/c so homey don't play dat.
 
Hmmmm.

Take a real good look at whats behind the radiator, the engine and there is not exactly the best situation there to induce a free flow of air.

The air sort of stacks up in front of the grill. Some flows through but to really get cooling, ya need the propeller sucking it through.

Now over at the Page, Jim did the Power project back a few years. The truck was built to the hilt with a turned up DB2 and all the goodies.

They did the HO water pump, dual stat crossover and a few other mods. There was never any mention of troubles keeping things cool.

Now that said, running an aftercooler and knocking the top off the EGT's will help a bunch at keeping the engine temp down.
A better turbo with less restriction lets the heat out and allows the setup to work far more efficiently.

With all good components, there is no good reason for these engines not to be running within normal temps.

Unless the fan clutch comes on at around 210 and reeeeeeeeeeeeeeeeeeeealy sucks the bugs in the thing is not gonna cool down.

The factory fan clutches DO NOT ENGAGE until around 220-230 which is way too hot.

Once the air starts flowing the temps will drop, and fast.

MGW
 
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I cheaped out and just cleaned the rad. I used condensor clearner the a/c guys use and holly crap was my rad plugged. I had to wash it 5 times for it to come clean. This stuff sprays onto the fins and then within 5 minutes it's all foamed up pushing the dirt right out of there. It looks like a new radiator now. I did the same with the a/c condensor but couldn't take it out to do it. I can see through it now. This should help out some.
I ditched the vac pump while I was in there and will do the fan mod as well.
 
Joey D said:
I cheaped out and just cleaned the rad. I used condensor clearner the a/c guys use and holly crap was my rad plugged. I had to wash it 5 times for it to come clean. This stuff sprays onto the fins and then within 5 minutes it's all foamed up pushing the dirt right out of there. It looks like a new radiator now. I did the same with the a/c condensor but couldn't take it out to do it. I can see through it now. This should help out some.
I ditched the vac pump while I was in there and will do the fan mod as well.
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smart way out... and proper maintenance. Should make a world of difference.
 
If your radiator core is clean inside then you should be fine.

Just make sure your fan works when the temp gets up to around 210 on a pull. If the fan will not engage then there is an issue with the clutch.

Once those clutches engage though, the temps fall like a rock.

The bugs all hang onto tree limbs in fear.

Missy
 
Did the fan mod as well, very easy acualy. I removed the vac pump but got the wrong belt, I had a 2550mm belt in the garage so I used that for now to run the truck and bleed the system out. I drove the truck around without the fan for the coolant fill and bleed. It got up to 190 on the scanner after driving around town a bit.
What is the right fan belt I need? I bought one for a 93 assuming they had no vac pump on them but it's to long.
 
Missy Good Wench said:
Hmmmm.

Now over at the Page, Jim did the Power project back a few years. The truck was built to the hilt with a turned up DB2 and all the goodies.


MGW
Click to expand...

DB2=less fuel than chipped DS4. I'm not running hot all the time. ONly towing heavy on long grades. I could burn down the highway doin 110 on a 90 degree day empty with no issues but hit a long hill with that 26 ft camper on the back and up she goes. I have done everything said here and then some. Still have a problem. Even the local Witchdoctor was bewildered and he gave my ex the clap....:D
 
Heard alot of people get a chirp out of thier trucks after vac pump goes bye bye. That's why i never took mine off. It's still on there doin a whole lota nada.
 
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I have a new (rebuilt, hot-tanked) engine, new heads, new radiator, new water pump, new thermostats, all new hoses, new surge tank, new cap, new AC condenser, new Heath fan and clutch, new Lube Specialist oil cooler and I cleaned the tranny cooler. I have new Dexcool with distilled water. Everything is new except the heater core. I rinsed that out with tap water, then distilled water.

I live up a long hill, speed limit 30 mph. Before I replaced the rad, condenser, clutch and fan, my truck would be just crossing 210 as I came to my street, about half way up the hill. Just past my street, the hill gets very steep, certainly over 9%.

After I replaced the fan and clutch, but with the old rad and condenser, I could go a block past my street, then the thing would heat up to 210. Once I replaced the rad and condenser, I now can go all the way to the top. The gauge is just about at 210 near the top, then I can hear the fan roar, and it maintains at 210. Previously, once it went past 210, it just SHOT up.

This all with the truck empty. I hate to think what's gonna happen when I hook my 7800 lb travel trailer and pull Logan or Parley's Canyon. I'm gonna get a brake controller pretty soon (wallet woes) and then we'll see.

The cooling system on these trucks is inadequate at best. The straw that breaks the camel's back on the undersized system is having the AC condenser up front. When the AC is off, I don't overheat. When it's on, I do.
 
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