razvy

To Bocatrip ...
Another cause could be the antifreeze , old antifreeze eats away aluminum like jelly donuts, radiator erodes away easily .

Also, the coolant can serve as an alternate path to ground , loose or corroded engine ground straps can cause this effect , use a good voltmeter to find the condition of the coolant and grounding straps . Dump the old coolant every 5 years .
Electrolisis corosion can destroy , intake manifolds , head gaskets , thermostat , water pumps ,,, on and on .. coolant hoses also can degrade the reason is the synthetic rubber they use to manufacture .
So ,,, don't point a bad finger on Denso for failure ,,..
Hope this helps .

Bocatrip

All the coolant was changed (Red Toyota, during each radiator exchanage) as well as the thermostat.. Currently my last Denso replacement is holding up just fine.

ibrahim83

Were all three dealer branded denso or denso aftermarket, aka first time fit?

Bocatrip

From the very first replacement of my original factory Denso, all 3 were aftermarket installed by Lexus. Currently, my last Denso (3rd) aftermarket is holding up fine so I have my fingers crossed.

StanVanDam

I'm very wary of Denso's aftermarket radiators - too many reports of failures, and the 12 month warranty only applies from the date of first purchase, not from the date of the replacement part, meaning if your replacement fails within 12 months of your first purchase date, you are out of luck. This is common warranty practice across multiple industries, but given the failures reported here and at https://www.clublexus.com/forums/ls-...r-leaking.html and at https://www.ridgelineownersclub.com/...-parts.224598/, and elsewhere, I'd rather take my chances with another aftermarket brand (OSC).

My prep for last year's long roadtrip was a new AISIN timing belt kit with tensioner and waterpump, installed by Toyota, + Michelin Pilot Sport 4 tires. This year's prep for a long roadtrip is:

(1) DIY install of a new radiator and hoses. Using RockAuto, I ordered an OSC 5/8" core (non-towing) radiator (the 1" core is the towing version). The only reason I went with the 5/8 core was to save more than half the price of the radiator in shipping, since the OSC 1" core came from a separate location from the other parts. OSC comes with a limited lifetime warranty but no cap, so I ordered new STANT 10242 16psi cap (STANT makes the original Lexus cap per parts.lexus.com), new AISIN THT015 180F thermostat , AISIN THP108 thermostat housing seal, and MAHLE 31699 thermostat o-ring. Ships today the 14th and should arrive here in Canada on the 17th, all for $186 USD after shipping&taxes&customs&duties. Also ordered new Lexus upper and lower hoses and clamps from LexusPartsDirect.ca, as I don't trust aftermarket hoses or clamps. RockAuto sells AISIN pink SLLC but it doesn't ship to Canada

(2) had an indie shop refinish the inside of my leaking chrome wheels per https://www.clublexus.com/forums/whe...with-pics.html

Bocatrip

UPDATE: As the OP of this thread, I just wanted to mention that as of today, my 3rd aftermarket Denso radiator is still holding up. It is now 4 years since the install. Maybe 3 times is the charm? Regardless, I just wanted to update, for any members out there considering the aftermarket Denso. Just to repeat, I did have Lexus install all 3 aftermarket radiators, and all the replacements did fail relatively quickly, although one took over a year and Lexus still replaced it as if under warranty. I guess it's the luck of the draw.

CSA

Folks are right to be wary of Denso aftermarket radiators. Despite my request for a true OEM radiator for my 96 Land Cruiser, the shop installed an aftermarket Denso radiator. It leaked like a sieve from day one. It served them right when they had to re-do the job and install a true OEM radiator like I asked them to the first time.

bigal426

On my LS430 with 125,000 miles on it, I did a timing belt change myself. While removing the radiator, I notice it was packed solid with dirt about a 1/3 up from the bottom. I tried compressed shop air to remove it, but it was packed in there too tightly. I probably should have tried some water from a hose, but did not. I purchased a new Denso radiator with tow haul for around $125 from eBay. It has worked well for me here in Michigan for 15,000 miles even with all the road salt on the roads. Yes, I know that Denso now is not the old Denso, but so far so good on the radiator. I would try them again if I had to.

ls430w140

I have aftermarket Denso radiator for almost 4 years now, and it has NO signs of wear. Cools the engine amazingly well. Denso provides the quality product for the low price. I do not trust any other aftermarket manufacturer for our cars when it comes to cooling systems.

The only concern I may think of is if Rockauto shipped the "chinese" manufactured Denso part, rather than of Taiwan or Vietnam origins.

kos

iTrader: (1)

Installed a Denso towing capacity radiator last night, everything went smooth as, except I didn't think about the core thickness affecting the lower hose position, and managed to almost rub through it on one of the serp belt pullies. So the original hose is back on the car for now. But other than that, straightforward install.