that's how I did it about 2 years ago, in September with new timing belt and waterpump etc, did it again before, and then just an easy flush again to rinse any crud out I might have broke loose. Figured I would do the hard flush with old parts and let the old parts eat any crud
Filthy cooling system
- Thread starter T4R2014
- Start date
that's how I did it about 2 years ago, in September with new timing belt and waterpump etc, did it again before, and then just an easy flush again to rinse any crud out I might have broke loose. Figured I would do the hard flush with old parts and let the old parts eat any crud
The spill free funnel is a good thing, it really helps purge the system. Used it on a ford also that had a purge issue.
T4R2014
Elite Member
WELL, the 3 year old Taiwan Denso decided that it didn't want to hold water overnight. It is leaking from the bottom tank at the crimps. Pathetic piece IMO, it is so cheap compared to original. Nothing beats a Japanese Denso. Mechanic was somehow able to warranty it(I love WorldPac), so F this. Handing it over to him on Monday.
BamaDrewski
New member
I have had exceptionally good results with ThermoCure (from WalMart). This is what I did:
1. Drained coolant.
2. Filled with distilled water and Thermocure.
3. Ran engine (and the heater) for about 30 minutes.
4. Drained (Water was dark brown)
5. Filled with Distilled water.
6. Ran for 30 minutes.
7. Drained (water was half the color brown as the 1st flush)
8. Filled with Distilled water.
9. Ran for 30 minutes.
10. Drained (water was very light brown - could see through to the bottom of the bucket.)
11. One final flush with distilled water - almost clear on drain.
12. Filled with 50% Toyota Red and Distilled water.
IMPORTANT: always run the heater when flushing to clean out the heater core. I had great results with this approach. Good luck. And by the way, the 5VZFE engine I did this on was a 2002 Tacoma with 200K+ miles that never had a coolant flush, water pump or timing belt job. Runs like a top now.
1. Drained coolant.
2. Filled with distilled water and Thermocure.
3. Ran engine (and the heater) for about 30 minutes.
4. Drained (Water was dark brown)
5. Filled with Distilled water.
6. Ran for 30 minutes.
7. Drained (water was half the color brown as the 1st flush)
8. Filled with Distilled water.
9. Ran for 30 minutes.
10. Drained (water was very light brown - could see through to the bottom of the bucket.)
11. One final flush with distilled water - almost clear on drain.
12. Filled with 50% Toyota Red and Distilled water.
IMPORTANT: always run the heater when flushing to clean out the heater core. I had great results with this approach. Good luck. And by the way, the 5VZFE engine I did this on was a 2002 Tacoma with 200K+ miles that never had a coolant flush, water pump or timing belt job. Runs like a top now.
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T4R2014
Elite Member
I saw that Thermocure stuff at Walmart. Pricey but I hear good things. Wasn't so impressed by the Prestone flush, but then again it was only $4.
It's really odd, but my 4Runner with the best heat is the one that has had green coolant in it since we bought it in 1996. It has been changed on time and the heater on that one will burn your face off within 10 minutes of running. My 1998 has clean red coolant and it only gets super hot after 20 minutes of driving. Maybe it needs a flush? The other green 1996 I'm doing this flush on now has heater performance on par with the 1998.
It's really odd, but my 4Runner with the best heat is the one that has had green coolant in it since we bought it in 1996. It has been changed on time and the heater on that one will burn your face off within 10 minutes of running. My 1998 has clean red coolant and it only gets super hot after 20 minutes of driving. Maybe it needs a flush? The other green 1996 I'm doing this flush on now has heater performance on par with the 1998.
BamaDrewski
New member
Thermocure is pricey but worth it IMO. We all want our rigs to be running forever so a good cleaner is worth it. Also, I have spoken with Toyota mechanics who say green coolant can cause major problems in a Yota. I have always run red and always will. It is also pricey but worth it. 311K+ miles on mine and all is well.
T4R2014
Elite Member
Yeah, it has me so conflicted. The green coolant is all that truck has run, but the OCD in me has me wanting to convert it to SLLC pink. At the same time the experience in me says not to dick around with what works.
ToyotaBrah
Member
I've got a Taiwan Denso on mine as well. I haven't had any issues with the radiator leaking, although I haven't inspected it at the crimps. I agree, though, that it is quite inferior in design compared to the original Toyota unit.
Is the Zerex coolant on par with Toyota Red? I'm planning to do a proper coolant flush on mine in spring.
T4R2014
Elite Member
I am kinda disappointed that I'm replacing it with the same piece of crap, but it's whatever. It was and still is the 4Runner I drive the most. It's a weirdly optioned SR5 that has been used to it's fullest since day one, and it has all the patina to prove it. Now that I don't drive it much, I don't think that the $350 for the OEM Denso is worth the extra dough right now. I have two other more deserving candidates for one of those. I guess if it fails in three years I'll warranty it again.
I've heard nothing bad about the Zerex, but again this is my ugly truck and I decided that it deserved a cooling system refresh with some of that fancy new HOAT coolant. Now that you can buy this coolant at walmart, I figured it's a no brainer. My mechanic argues to use either OEM or Pentosin brand. I guess from a business perspective the Zerex isn't proven enough.
T4R2014
Elite Member
These Denso radiators are a total joke. Two have been delivered and both had broken overflow necks. They both arrive with the packaging foam scattered around the box. I recommend none of you guys waste your time on this radiator. It is just a brand name applied to the same cheap garbage. Let's see if I can get another aftermarket brand. At this point it's a competition for packing material.
I'm reading other radiator reviews. These China radiators only last about 3 years no matter the brand. Some of you may not get lucky with warranty. $350 for the Japanese Denso is peanuts.
I'm reading other radiator reviews. These China radiators only last about 3 years no matter the brand. Some of you may not get lucky with warranty. $350 for the Japanese Denso is peanuts.
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thegipper
New member
Hmm. I have one of those Taiwan Denso's and I haven't had any issues with it. It's about 4 1/2 years old now. It spent it's first two years in Phoenix and last 2 1/2 years here in Wisconsin. It seems to be holding up great but I'll definitely keep a close eye on it now.
PS. From everything I've read, the Zerex brand coolant is great and you shouldn't have any issues with it. I used to be a purist and bought the OEM coolant. I also noticed that walmart is now selling Valvoline "toyota/lexus" coolant with "zerex technology". I have no clue what that means.
I usually buy the actual Zerex brand "asian" coolant that is specifically for toyota/lexus at advance auto. I buy two gallons at a time online, use one of their coupon codes and it comes out to be like 10 bucks a gallon.
PS. From everything I've read, the Zerex brand coolant is great and you shouldn't have any issues with it. I used to be a purist and bought the OEM coolant. I also noticed that walmart is now selling Valvoline "toyota/lexus" coolant with "zerex technology". I have no clue what that means.
I usually buy the actual Zerex brand "asian" coolant that is specifically for toyota/lexus at advance auto. I buy two gallons at a time online, use one of their coupon codes and it comes out to be like 10 bucks a gallon.
96RedRunner
Senior Member
Zerex brand "asian" coolant that is specifically for toyota/lexus.
Deciding between Yota Red and whatever brand on 01 198k mi I got 2-17 after Rad change.
All the talk was going on about Yota Red, I looked at chemical makeup of Zerex asian,
don't recall the specifics they are the same where it's important.
Going on 2 yr of use all looks well.
Deciding between Yota Red and whatever brand on 01 198k mi I got 2-17 after Rad change.
All the talk was going on about Yota Red, I looked at chemical makeup of Zerex asian,
don't recall the specifics they are the same where it's important.
Going on 2 yr of use all looks well.
T4R2014
Elite Member
Honestly at $13 a gallon it's cheap enough for me to get changed often. Can someone still explain why my original 3rd gen has insanely good heat compared to my other two? Maybe thermostat position? That thing was burning my face off after only running for 5 minutes in this 10 degree weather. The type of heat where your eyeballs feel like they are cooking.
thegipper
New member
I'm not sure, could be a bunch of different reasons.
My 97 with the Zerex coolant gets the air temp insanely hot, very quickly. Only vehicles that I've ever owned that was better than my 3rd gen were my mid 80's Jettas that I had. They would actually burn your skin if you held your hand up to the vent.
Went from green that the PO of my truck had put in to toyota spec, and getting the truck to blow hot air hasn't been quicker. The difference was night and day.
gamefreakgc
Elite Member
These 4Runners really do like that OEM fluid, or whatever equivalent of red/pink you can get your hands on. The dirtiest and most scaled radiators I've ever seen on Toyotas all had green coolant, I don't think it's coincidence.
T4R2014
Elite Member
Well, an interesting heads up. The Denso that got installed now came packaged very well. This Denso was made in 2018 in China. Looks like our communist enemy makes a better radiator than our Taiwanese buddies. Been running it for two weeks and all is well. I expect it to last three years.
LittleCaesar
New member
The Koyo from Indonesia has been on my rig since 2008 with zero problems.
Did you keep the green coolant?
My dad’s 98 k1500 can blow 170f once warmed up. His was made in Canada. No other family member’s ride can go past 150f on any day. No idea why. My Limited’s HVAC is good but not exceptional. Red coolant since day one......
Did you keep the green coolant?
My dad’s 98 k1500 can blow 170f once warmed up. His was made in Canada. No other family member’s ride can go past 150f on any day. No idea why. My Limited’s HVAC is good but not exceptional. Red coolant since day one......
T4R2014
Elite Member
I think aftermarket parts were way better 10-15 years back. Nope I switched it to pink. Maybe it needs to bleed longer. With that said it does not beat my 1996 with green coolant. Never held a thermometer to it, but it gets damn hot damn quick.
I ordered a Denso from Amazon for less than $110 and opened the box today. It was made in China. The box was wrapped in bubble wrap, but that wasn’t enough- the overflow fitting on the radiator neck was broken off and laying in the bottom of the box. So, off it went for a return. The foam stayed on the corners, but the side of the box was caved in slightly, with a small hole where the fitting punched through before breaking.
Mine’s a 1999 w 230k that I just picked up. Very clean, rust free vehicle. I’m doing brake and suspension repair/upgrades and purchased the new radiator as PM. It looks like it has the original radiator. It’s filled with the green stuff, but I drained some into a white bucket, and it’s very clean. Previous owner had good records of regular fluid changes and flushes.
I’m now considering disconnecting the transmission coolant lines at the radiator and just going to a B&M or similar trans cooler, and leaving the oem radiator in place since it has no known problems and looks very clean internally. I’m thinking flushing the green out and going with the Zerex Asian coolant.
I’m new to the 4runners, but reading a lot of info on this forum that is very helpful.
Thoughts?
