Cooling System

My major beef though, I wish Denso would've separated the two in a contained way that made it impossible for pink milkshake. It's irritating to realize you could completely nuke your tranny because of a simple failure of aluminum, especially when you consider that soft aluminum is in an area that's directly exposed to high-speed road debris.

I wish Denso had an option which eliminated this risk, but with how old our trucks are at this point, I don't see it happening, and the only option to avoid it is spending 2x-4x as much on aftermarket.

 

Did not know this. Thank you for the knowledge. My options are open now. Will be looking at radiators after I get off

 

You can eliminate this risk by not hooking the trans line up to the radiator. It helps get the fluid up to operating temp faster for better performance more than it helps cool the fluid down. Radiators operate around 195-210 degrees, we all think our trans fluid should be 150 degrees all the time or it's gonna burn. Just run an aftermarket trans cooler with a thermostat on it and deal with the slow warm up that will cause harsher shifts.

 

Did it fail at the hose connection?

You're kidding, right?

 

It just started to split on the upper plastic part of the tank from old age. Not kidding about the 18 years. Kidding about being upset that the part lasted that long. That's a good run for any part.

 

Same thing happened on our 02 Corolla. It developed a small leak in the plastic at around year 13 and 190K miles.

 

It is a bad design. With that o-ring being the only thing keeping coolant and ATF separate.

This is a better design where the connections are made outside the radiator. So if one seal fails, coolant leaks. If the other seal fails, ATF leaks. But the only way for the two to mix is if there's a catastrophic failure of the actual cooler -- which is highly unlikely.

The real world solution is to just replace the radiator as preventive maintenance every 10 years. You should be flushing the cooling system twice in that amount of time anyway. So do it every other coolant flush.

 

That's what I thought you meant. Agreed, 18 years is a pretty good run.

 

Very nice explanation and pics! Kudos sir.

 

*UPDATE* Plan on ordering

$170 DENSO 2210517 Denso 221-0517 Radiator

DENSO 2210517 radiator. Wanted to know if summit racing has good shipping? The auto parts stores in My area do not have any in stock so I can go in store to pickup. Have to order online. Amazon has the part but I know for a FACT the part WILL be damaged with Amazon shipping. If this is my only option then I will go ahead. Plan on upgrading to moshimoto before next spring.

 

Yes! I love Summit. I often pick up local for things like radiators that tend to get damaged in shipping.

Summit is also super-easy on returns.

 

Yea, I literally live minutes from the summit store but just my luck that they don't have the part in stock until October 7th. Was pondering on waiting till the date but my birthday is October 3rd and I need my truck lol

 

Just order online, use a coupon, have it shipped to your house. If damaged in transit, return it and tell them you want to have another one shipped to the house. Repeat until you get an un-damaged unit.

But I suspect they'll get it to you intact the 1st time. I've only ordered one radiator from them, and it fared totally fine.

 

I got mine from Rock Auto. I've ordered 3 radiators from RA -- well, actually 4 I guess. One several years ago for my 4Runner did arrive with the overflow nipple broken off. They paid for the shipping back, and when they received and inspected it, refunded the purchase price and the initial shipping charge. In the mean time, I ordered a second one and it arrived fine. Everythiing else I've ever ordered from RA -- and it's been A LOT -- has been perfect.
Within the last several months, I ordered two more radiators from RA: one for my Tundra and one for my mother in-law's Suzuki. Both arrived in great condition. It seemed to me the two recent ones were packed better to protect the neck and overflow nipple.
BTW, I don't recommend buying auto parts on Amazon -- too many counterfeit parts. The exception being if it's from a Toyota dealership store or from the part manufacturer's store, like Denso, Bosch, Hitachi, etc.. A "Denso" radiator from an unknown Amazon seller to me would be a bad bet -- especially when there are legit options like Summit or RA.
I got burned buying Denso Iridium spark plugs on Amazon. They were neither Denso, nor Iridium... lesson learned.

 

Just to expand on this point b/c I fully agree, A-Zon if full of damn counterfeits, many people here have been burned and vehicles damaged from buying on A-Zon!!

Clicking on the VISIT XYZ STORE link does not protect you. A-Zon can still choose who is fulfilling the part, despite you choosing a specific storefront. If your item says "fulfilled by Amazon" on your purchase, all those parts are getting pulled from the same bulk stock bins at the warehouse. There's nothing concrete stopping someone from sending a batch of bogus inventory to the warehouse and it landing in the stock bin, from what's been shared with me.

Here's what to look for, for those who aren't familiar w/Amazon. The best chance of protecting yourself from counterfeits on A-Zon is to make sure the item is not "fulfilled by" or "shipped by" Amazon, and instead the specific item you've selected is shipped by a trusted source (like, the actual manufacterer and not some no-name source!). That info is normally in the Add to Cart area on the right. For example:

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However, everyone using A-Zon needs to understand. You can often switch who/what is fulfilling your order and where it's shipping from. Many (not all) items have a link near the bottom of the description allowing you to change who is fulfilling and/or which vendor is shipping. Example link is here:

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If you click that link, you have an option of multiple vendors to choose from. You can clearly see who is shipped by. Now tell me... of these three, which are you going to trust? I'm damn sure not trusting "Dropped Price Sales" to get me a genuine OEM part, so I'm adding-to-cart on the one that appears to be a Toyota dealership, frankly. And even then, it's important to understand A-Zon has zero control over someone naming themselves "Santa Margarita Toyota", so you may want to at least confirm that dealership exists first. But really, why even risk it? Just go to parts.toyota.com and use their online dealership referral program, and enjoy that discount.

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With the engine cool and has not been running, fill the radiator to top and make certain the expansion tank is at level, put the cap back on and run truck hard for a few minutes. The expanding fluid should show up immediately and the expanding pressure forces itself thru hole, crank or whatever problem you got going on, if is coolant related.
Good luck,

 

Great info. I was unaware of how much of that worked. Thanks for posting!

This should be a sticky!