Sourcing and Fitting Two-Core Radiators for 2003+ Chevy Vans

[booster]

Several users have been looking for the big radiator like we used in our van and a few others in theirs, but they had all disappeared from the market. I got probably the last Spectre one from an out of the way parts house in Missouri last year so we would have a spare.

Rock Auto is now showing 3 different brands for the 2000-2002 8.1 engine vans and one brand for the 1999 and older 7.4 engines. I thought all the old body style big block radiators were the same and I didn't dig into what the difference might be. It could be as simple as being different thread on the cooler fittings even.

One of the 8.1 engine ones is on closeout for just over $200 which is pretty reasonable.

This might be a last chance to get one if you are looking for one.

 

[Bangorbob]

Are you saying the 2000-2002 8.1 rad will fit in a 2..4 Chevy

 

[booster]

Are you saying the 2000-2002 8.1 rad will fit in a 2..4 Chevy

I just went and looked at my old thread that I posted when I did ours and I used a 1998 for the 7.4L gas engine and it fit with very minor work.

1998 Radiator install

We would need to check to see what changed when they went to the 8.1L but it would probably be inlet and outlet changes or cooler threads. The do list one brand for the earlier years like I used, but it is a bit more expensive.

 

[booster]

I just looked at the listed specs and the difference is the inlet diameter.

The older one is the same size as your 2014 and our 2007 so my install would be the same as yours and my thread would be correct. You would still have to adapt the lower hose to go from the quick disconnect on our vans to straight hose as described in the thread. The vent/steam hose to the radiator would also need to be adapted I assume. What we don't is if your radiator has a temp sensor in it like some newer vehicles do. Ours didn't have one. That can be addressed with an in hose adapter most of the time without a huge issue.

I make all my own adapters as I have a lathe and the other necessary tools, so those would have to be found in the aftermarket.

As I said not a huge job, but does take tools and mechanical knowledge to do. The thread should let you know if it is in your range or not. Hiring it done would probably be at least as much as the radiator is.

 

[Bangorbob]

Booster, As always you're here when someone needs advice. BTW, I obviously mistyped my year. I have a 2005, with a 2004 Chassis.

 

[Bangorbob]

Booster, I found this but don't know what sensor they are talking about. ????

Radiator 2004 Chevrolet Express 3500 - 6.0 Liter V8 364Cid Radiator 3 Row All Aluminum Clamp Style Hose, No Sensor | Radiator Express

Rush delivery of Radiator 2004 Chevrolet Express 3500 - 6.0 Liter V8 364Cid Radiator 3 Row All Aluminum Clamp Style Hose, No Sensorfrom over 100 nationwide locations. Order online or call 1-866-723-3977

www.radiatorexpress.com

 

[youngnretired]

I believe this is the location where any sensor would be installed. It wasn't present on our 2007 Express. Look down the passenger side of the radiator tank and if you don't see a wire running to a sensor in this area, then you don't have a sensor.

 

[Bangorbob]

Okay, what is the sensor for?

 

[youngnretired]

I don't know, but I'm going to guess that it would be related to control of an electric cooling fan or some other input to the ECM for control or monitoring of the coolant on the cold side of the radiator. It may also be used to shut off the AC system if the coolant is too hot. The passenger based Express/Savanna vans that have dual AC may have additional sensors on them for control of the interior systems. This radiator may also fit other chassis that use this sensor.

 

[Bangorbob]

Here is the info:
The sensor on the side of a 2004 Chevy Express 3500 radiator is the Engine Coolant Temperature (ECT) sensor (or radiator temperature sensor). It monitors the temperature of the coolant to manage engine performance, control the electric radiator cooling fans, and operate the dashboard gauge.

 

[youngnretired]

It can't be for the gauge on the dash as it doesn't represent actual engine temperature since it's on the cold side of the radiator. Everything else you list, yes, could be used for those.

 

[Bangorbob]

I found this online. It is not my explanation

 

[youngnretired]

I found the same thing, but since the online response could represent any sensor on the radiator, I ruled out that it would be for the actual engine temperature because of it's location in the cooling system.

 

[booster]

The OP has mistyped his year and it is a 2004 so shouldn't have anything to worry about.

Here is the info:
The sensor on the side of a 2004 Chevy Express 3500 radiator is the Engine Coolant Temperature (ECT) sensor (or radiator temperature sensor). It monitors the temperature of the coolant to manage engine performance, control the electric radiator cooling fans, and operate the dashboard gauge.

My guess is that this is only partially true at best by probably not correct at all for vans with no electric fans.

No engine I have ever seen would control engine management by the PCM based on radiator temperature as it doesn't represent engine operating temp closely at all. The engine is controlled by temp sensors in the block, heads or other engine points and they are called engine coolant sensors. Electric cooling fans, yes, that is what the commonly used for but our vans don't have them. The dashboard gauge would also never be controlled by radiator temp as it would be wildly swinging all over the map, while the engine operating temp stayed stable.

 

[booster]

I found the same thing, but since the online response could represent any sensor on the radiator, I ruled out that it would be for the actual engine temperature because of it's location in the cooling system.

Totally agree. Fan control for electric fans at most, but only one of the as the engine temp sensor will control fan speed based on actual engine temp vs target, off/on/high speed. One in the radiator might have an input to that decision somehow as things like AC on do.

 

[Bangorbob]

So basically, the rad I recently mentioned is a crapshoot?

 

[youngnretired]

I had previously considered going with an aftermarket aluminum one last year when I did our conversion. I decided against it because of possible time and fitment issues as I don't know how the bottom or top is set up to be held in place by the factory mounts. Basically, I didn't know if I needed to create custom mounts to mount it, and wasn't interested in creating a custom mounting means. I had also read some reviews where the radiator failed fairly quickly. I suppose that can happen with any aftermarket item though.

 

[Bangorbob]

I assume all the work you have done kept the engine and trans temp in check? I know you took a trip to death valley after the work was done. Was it worth it?

 

[youngnretired]

Everything was great for the trip. I had received my Scangauge II and the next day took the van for a ride when it was in the upper 80's to check trans temps. It was right after that where I started on the radiator swap and external trans cooler install, so I didn't have any real time with monitoring anything with the original radiator and the route 66 trip was really the first long trip after the changes. On the trip, engine temp never ran any higher than 198, except when you sit at a light, but just touching the gas when the light went green had the temps drop right back down.

What the swap/upgrade did was gave me peace of mind for an unknown that I didn't know what I was in for. We had ambient air temps in the mid 90's on the trip, and with the AC on, it never ran above 198, even climbing hills. I also installed a new heavy duty fan clutch and new waterpump while the work was going on. I'm going to work on my transmission cooling additional upgrades this spring, but we have a maritime provinces trip being planned for early this summer, so I don't know if I'll get to the transmission cooling changes in time or not.

Oh, and by the way, I did find that when you turn the in-cab heater on just the slightest bit, the engine runs at a hotter temperature. The 198 degrees was running without heat on. With the heat on, engine ran up to 208-210. Must be the way they circulate water because this was consistent when the heat was turned on just the slightest the temperature would rise. real hard to see this on the factory temp gauge, but easy to see with the Scangauge II

 

[Bangorbob]

What was the highest moutain you climbed coming out west? Also, a little strange that turning the heater on would make the engin temp rise.