1998 Toyota 4Runner, 3.4L Auto w/ 127k.

First off, I'd like to say, as far as I know, my radiator is stock/never been replaced.

Second, about 2 months ago the timing belt, water pump, seals, pulleys, and thermostat were all done.

Now I know I would overheat before the timing belt job was done, and after that I thought it would be fixed. Well about a month ago, driving maybe 20-30 minutes on the freeway, then up a pretty decent sized hill, I found myself overheating.

On that trip (a wheeling trip it was), I was overheating the whole time wheeling (had to have the heat cranked the whole way, the whole time, no fun).

Then today, after some simple around town driving, I was waiting in the drive-thru (for like 20 minutes, their debit machines weren't working properly) to pick up some pizzas for the family, the temperature gauge started rising. WHAT THE HECK?! So I blast heat until it went back down, then shut my truck off.

I got home about 2 hours ago, but I just went outside now to check on it, and the temperature was just a little under where it should be when my truck is warmed up (right in the middle). Wouldn't you think it would be pretty cooled down by now, I mean 2 hours, really? Anyway, I'm going to Montana in a little over a month, and can't have this problem when I head out. What do you guys think I should do? New radiator? Thanks for anyone that can help.

 

If it only does it when you are stationary or going slower, your fan clutch is suspect.

 

check your radiator fins and make sure theyre not full of crap. check the coolant and make sure its good and full and clean. id also check your fan. it has a clutch that allows it to continue spinning after stopping and if it gets stopped, its less likely to screw up the fan. but if the clutch is bad, the engine isnt spinning the fan so there for if not a lot of wind is coming through the front, it will overheat

 

That could be a possibility, yes. Could this happen if I'm on the freeway for a good amount of time, then get off and start going at a slower speed and/or stopping? When I did my body lift at Vitaly's a few weeks ago, the temperature started to creep up just a tiny bit once I was at his driveway. Only took me 20-30 minutes or so from Kent to Kirkland on 167.

 

yes that sounds like it.
check this
http://www.youtube.com/watch?v=xHdEp...eature=related

 

Redhawk427, during the power steering pump job, the radiator was sprayed down and got a lot of that crap out of the fins. Also flushed the system, and still, the coolant is good and clean.

Edit; thanks for that video too, I may have to try that out!

 

then i bet its the fan clutch. any water crossings recently? deep water?

 

Recently? I'll have to say no on that one. After wheeling with some of the NW Yota guys about a month ago, it was mainly mud, some going through water, but not really that deep, couple feet maybe.

 

it could have started the problem but fan clutchs just go out like any other part. i dont remember it being too expensive for my 3vze

 

I'll definitely have to try that magazine-into-fan trick shown on that video, maybe tomorrow at work I can give it a shot and test it out. Thanks again man! Still looking for some tips/suggestions on what it might be!

Off for tonight. 900th post, uh-woop!

 

no problem and keep us updated

 

... i was gonna say fan clutch too... also cody... maybe you should replace the tranny cooler with an aftermarket unit to prevent the strawberry milkshake.

 

Yeah, I would also recommend replacing the radiator / installing a transmission cooler to prevent milkshake.

 

I'll check that fan clutch today at work.

Vitaly, gdutch; that also has passed my mind. Do you recommend changing my radiator AND getting a tranny cooler, or just doing one? I really never want to run into the milkshake problem, would doing both be the best way to go for this? And like I said, my current radiator (as far as I know...) has never been replaced.

 

My rig is over heating too. I'm pretty sure its clutch fan also. I will be replacing it with electric. Flex-a-lite or something.

 

12 years is getting well into old age for a radiator (its like dog years). If you never want to get a strawberry milkshake do the external cooler. So I guess I'm saying do both, but do the external ATF cooler ASAP.

 

Its really hard to beat a Taurus or MarkVIII fan for massive air flow. You want at least 2500 CFM, 3000 is better.

 

Michael, that sounds good. I probably wouldn't go through that much for just the fan clutch, but might just replace it with OEM.

mt goat; Thanks, I'll look into that tranny cooler tonight then (yay for payday today!), any brands you recommend? I saw that gdutch has a TruCool 4454, as shown in his signature. I'm really not sure of external tranny cooler brands and prices though.

 

Well my thing is, the 3.0, and the 3.4 are pretty slow. as much as you can take away from the rotational mass is probably good.

http://www.flex-a-lite.com/auto/html...c_x-treme.html

I was thinking of something like this 3300 CFM.

~Michael

EDIT Vitaly also has a great idea by seperating out the auto trans cooler, and the radiator. Will also decrease heat to your coolant system. This is a good thing to do.

 

If you're getting a new radiator anyways, I don't feel there is any point in getting an external tranny cooler for several years - the stock coolers are actually pretty efficient. It's not common for the internal coolers to rupture and cause the milkshake until about 150-200K. The brand new one that comes inside your new radiator will go a long time before you need to worry about it.

Another option would be to buy a 5 spd radiator - they're cheaper since they don't have tranny coolers inside them and then run an external cooler.