163k Miles - Time for New Radiator?

Hi All,

I got my '04 1500 Z71 about a month ago with 163,000 miles. Runs good, in generally good shape. I was wondering if you thought it would be advisable to change out the radiator. I  know the factory fill is DexCool, and my friend who is a professional mechanic with extensive experience with GMT800s said it appeared the coolant was probably original. Running around unloaded, I don't think it'll be an issue, but I'd like to tow with it at some point. For those of you with higher-mileage models, when did you replace the radiator (if ever) and are any of you towing with the original radiator with more than 100,000 miles? Thanks.

I tend to replace radiators when they start to leak and not before....

not meant to be a maintenance item...

There are some with performance upgrades to engine who have replaced radiator and they posted in here:
http://www.chevyavalanchefanclub.com/cafcna/index.php?board=110.0

Popular mod is to go to electric fans.

X2

Why fix it if it ain't broke, just change the coolant!


Didit

160k? That's all? Bah, radiator is fine, unless it is leaking.

I would change (not flush) the coolant. I've done it every few years on my '06.

I agree with what everyone else has posted, if it ain't broke don't fix it.  I have almost 260k on mine and it is still the original radiator, but I have changed out the coolant a few times already.

Do any of you guys tow very much? No major issues with overheating on higher-mileage models? Thanks.

no

I wouldn't think the high mileage would have too much effect on your towing engine temps.

One thing that you may want to consider, the fan clutch on your truck, if it hasn't already been changed, is most likely well worn.

Replacing the fan clutch will help mostly at lower speeds, both when towing and not.

And you may see a huge difference in your a/c performance at idle and in stop and go traffic.

You can not test your fan clutch by simply spinning the fan by hand when the engine is off.

Some think that if your have a real quiet fan when running, that the fan clutch is working properly.

Actually, you will find that when you first install a new fan clutch, you will begin to notice MORE fan noise, especially at a cold start and often at low speeds and even at idle.

A good working fan clutch should be more engaged at lower speeds (louder, in some cases) to help draw more air while the truck is not moving and should begin to slip more at higher engine speeds when the forward motion of the truck will allow enough air for engine cooling without assistance from the fan.

The temperature of the air hitting the front of the fan clutch can also effect how much the fan is engaged.

So, at lower speeds, the fan may be louder since the clutch has engaged to help draw more air to aid in cooling.

Therefore, if you never notice any louder fan noise under any conditions and/or your a/c does not seem to cool very well or your engine temps seem to rise while at idle or when driving in slow traffic, chances are you would see a big improvement by spending the $80 or so to replace that old fan clutch.

Also, changing out your radiator coolant and making sure your radiator and other cooling devices at the front of the truck are clean and clear of debris, is always a good idea.

If your truck does not already have one, investing in an auxiliary transmission cooler is a really good idea, towing or not.

Yep, an aux trans cooler is definitely on the list. Fan seems to be operating normally. I do get a little bit of fan roar at lower speeds. I'll have to check the service records to see if it was ever replaced.

Drain and refill using dexcool and distilled water.
Repeat again next month if you feel the need to get more out