I am currently having issues with my Toyota overheating on large grades and on the highway during the summer months of Arizona when it is over 100 degrees outside. On the highway it gets about 3/4 the way up my gauge and stays steady while on the highway. But on hills it has been able to peg out in which I pull to the side and let it cool off. Currently I am running a stock 3.4 4x4 radiator that I got from autozone. Aluminum with plastic reservoirs. Brand new when I put it in and used DI water to fill it. I am also using the mechanical fan and I have a fan shroud. Driving around town it works fine. Stopped and idling it is fine. And during most of the year when it is cooler going on the same highways and hills it is also fine. Only when the temperature starts to rise higher than 100 outside does it give me issues. I was wondering what radiators everyone has been running. I have been looking into a radiator from Davez Offroad Performance but I have been unable to get ahold of them to ask questions about their 3 Row radiators that they offer. Does anybody have recommendations for oversized radiators for a 3.4 swap?

 

Fan clutch is tired. Rebuild it or replace it.

 

I have not bought a Radiator since Radiator Barn went away .

I run the 3 Row Copper brass Radiators one in my 2000 Tacoma 3.4 the other in my 92 4Runner 3.4

This radiator is the one listed for the 92 3.0 Just the regulator stock fan set up no shrouds or stupid tool catches

Here in Pa we don`t have the heat of Arizona I have no cooling Issues even with the AC on.

No AC??

Don`t forget the condenser adds quite a load to the cooling system

I would check the fan clutch maybe double check the real temperature with a heat gun.

Quite possible there is a blockage in the radiator

 

Doesn't the fan clutch usually cause issues at idle and low speeds not at high speeds? With the ac on or off it does the same.

 

The current radiator is pretty new some I don't expect blockage. I replaced it lady year from the 2wd radiator for a 3.4 to a 4x4 version which I longer thinking it would help. The issues persisted so I just think it's the capacity in this heat.

Anybody else have thoughts?

 

I run a 3.0 fan and shroud, with a 3.4 fan clutch and a CSF 3 row all metal, from Dave'z btw for a 88 v6.
The 3.4 fan clutch is supposed to be better.
No problems here even with a.c. on and triple digit heat.

 

Do you like the radiator you got from davez? Seem well built?

 

It's fan clutch related. even if you're moving at freeway speeds, it still cools your toyota down.

 

I guess it just doesn't seem logical for me to the clutch fan to be causing overheating at highway speeds. Mainly due to the fact there is so much wind going through the radiator. In my mind the clutch fan wouldn't be spinning not at this speed. However, it is the cheapest part for me to replace so I guess I will explore it. Have you had a similar issue to this?

 

So I went out and tested my fan clutch. When I try to spin it free hand it barely moves after release. I don't think it's the fan clutch

 

Yes, no problems at all. Dave is hard to get a hold of sometimes, he works in the shop. I did slot the mounting holes for good clearance.
You could also try the cooler thermostat for the supercharger 180 from a 190 iirc. Do search those #'s and double check, I have crs sometimes...
I remember reading about the difference in the fan clutch on the ORS install instructions. Thermostat info on Gadget's URD site in the supercharger info section.

 

I have the 3 row CSF all metal rad in my 22r and I love it. No cooling issues at all once I installed it and I'm cruising around in that SoCal heat

 

those tests don't mean much, i tested a new fan clutch vs. one that was shot, i couldn't get find anything definitive.

however in my case it failed more as you indicated earlier, i.e., getting hot when idling for long periods, which has not happened since i replaced the fan clutch... the gauge had stayed under the half-way mark on the freeway.

i have a cheap aluminum radiator that has plastic caps, in a sas'd '86 4runner with armor and 37's, it's jacked up and heavy, it nearly has the wind profile of motorhome, lol, but it doesn't get hot even in triple digit california desert weather.

the biggest problem i had was the fan clutch, however i also replaced the thermostat that was stuck open, and added that missing plastic piece to the fan shroud.