4mydogs

Great forum! I came to see if I could get some help with a familiar topic – A/T OIL TEMP. My ’95 V-6 4WD never gave me this indicator UNTIL I had my mechanic “service” my auto trans at 92K miles. Then, while driving around 75 mph up I-95 in the heat of August, the light came on. I pulled off and checked the fluid level - right on the money, and no burnt smell or discoloration. Light off, drove 600 miles with no problem BUT there was a film of trans fluid all over the back of the truck. Had a mechanic at my destination check it out and he could find nothing wrong, no idea where the fluid came from. On my return trip the light never came on. That was two years and 38K miles ago. On every long-distance expressway trip since then the light has come on. (I had the trans flushed and serviced again – didn’t help). Doesn’t matter if the outside temp is hot or cold, in the mountains or the flatlands. On the last trip we were fine all through the mountains of NC, VA & WV in the heat, A/C on, only to have the light come on in Ohio with the A/C off. The level is always right on, and the fluid still has no burnt smell. After reading other forum posts I got the message: I need an auxiliary transmission cooler. Right?

I have traced lines from my trans to the bottom of my radiator. I don’t see any way to fit a cooler between the grill and the A/C condenser, so I have two critical questions. 1) Which cooler should I buy? 2) Where should it be mounted? Any help would be greatly appreciated!

leebee

search the members section for robinhood150, check out his website. he has a pretty good write up on trans coolers and installs. hope this helps.

lee

mt_goat

I just installed a Hayden cooler, here is the pic of where I put it: http://community.webshots.com/photo/...71697809PxiQaV

I have never even had my light come on, but I wanted to keep her cool anyway.

4mydogs

Thanks for your quick responses. MT, it looks like you have one heck of a lift and skid plate going on, but mine is just a stock set-up. Lee, I checked out Robinhood150’s website, and it’s great. I had figured that about the only place I could mount a cooler would be behind the skidplate, so it was nice to see how he did it. I wonder: what size Hayden cooler do I need? And it seems that I may not be able to find a Hayden as they’re getting scarce, so is there a close second choice? Thanks again!

mt_goat

Most of the major auto parts stores here have Hayden. I first tried the Rapid Cool 678 but it was just a little too big and I couldn't find a good fit so I took it back and got the Rapid Cool 677 (next size smaller) and it fit good. It would have fit in front of the AC condenser on mine too but I was hesitant to add the extra heat to the radiator. The AC condenser already blocks the radiator air flow some.

Gadget

In highway cruising your tranny temp should be at its lowest. If it is not, you have a problem that needs correcting. Putting a cooler on is a great idea, but not to cover up a repair that needs to be made.

First if your tranny fluid temp got hot enough to activate the light, you need to have that fluid flushed out ASAP. The activation point for that light is very high and once it gets that high you should flush out that fluid.

The most likely cause for this problem of yours is a torque converter clutch is not engaging in cruise like it should. If it does not engage the slipage in the converter will super heat the fluid.

One day I was driving along in my 96 and noticed the tranny temp gauge really high. I started checking things and it was my convert clutch had failed to engage. I started some diagnostic work and traced the problem down to the converter clutch solenoid in the tranny. It was an easy fix, just drop the pan, one bolt, one plug and pop in the new one. Done.

So, I strongly recommend that you get your problem diagnosed and fixed before you smoke your whole tranny.

Gadget

4mydogs

I read you loud and clear, Gadget. The strange thing is that the fluid looks and smells fine! Both times it did this on road trips, and afterward I had the trans flushed. Both times the mechanics said it looked fine. It showed no indication of the trans running hot - never has.

MTL_4runner

I have to agree with Gadget that if it is overheating in normal conditions you likely have a more serious problem. The tranny cooler is a precaution for using the truck in more extreme conditions and if you add one to cover the symptoms of a potential tranny problem, you will only make things worse. It is quite common for 2nd gens to need a shift or lockup solenoid replaced but it could also be the torque converter as well. If the tranny is not able to lock itself during operation the shearing of the fluid causes a HUGE amount of heat buildup and would likely manifest itself in the way you described. Other option is a faulty temp sensor but again these are all things to look at.

4mydogs

What you are saying makes sense. Otherwise ALL 2nd gen 4Runners out there would be having to add coolers. I guess I need to find myself a good transmission diagnostic person. If anyone has any helpful suggestions, I am all eyes. I'll let you all know what I find out.

Buki

If you still want/need a cooler here's a great place to get it. Not to mention they have a great line of synthetics and hydraulic accessories.
http://www.bakerprecision.com/setrab.htm

Richard

SLC Punk

If the fluid looks good, then it could be the sensor that activates the light.

lesha30

I agree!!! Check the sensor!!!

4mydogs

Sounds like a plan! Can the sensor be tested?

MTL_4runner

Yes, but you need to get a wiring diagram (better yet a FSM) to know where the signal can be accessed and what is the proper voltage reading.

midiwall

Ummm... that's REALLY expensive.

A few folks here have used Makco Distributors with great results. The Hayden 1678 is the one most folks run:

http://www.bulkpart.com/Merchant2/me...duct_Code=1678
$46 plus shipping.

They also carry TruCool like Baker does... but for a lot less:
http://www.bulkpart.com/Merchant2/me...egory_Code=TCC
The 4452 for $40 looks about right (it's overkill actually).


(btw, welcome to the forum!)

mt_goat

[QUOTE=midiwall]

The Hayden 1678 is the one most folks run:

QUOTE]

I think the 1678 and the 678 are the same. Hayden doesn't have a 1678 part number anymore.

4mydogs

RE the torque converter clutch, solenoid, slippage, etc. If this were happening, wouldn't I notice it? I've been driving this truck over 100K miles, and the trans SEEMS to work perfectly. If the torque converter wasn't engaging wouldn't I see the engine revving too high, or fluctuating revs? Also, wouldn't it do it all the time? This only happens above 65-70 mph.

mt_goat

I notice mine engaging, mostly around 65 mph. Sometimes it feels like there is a gear between 3rd and OD because the torque converter is doing its job. I drop it down out of auto OD for hills because I don't like to over use the torque converter.

4mydogs

Right, I know what you mean about it seeming like there is a gear in between. But if it were malfunctioning or slipping wouldn't it be noticeable, like it kept shifting up and down or engine revs changing? BTW, I have had the light come on on long, level stretches (like I-95 in southern S.C.) as well as more mountainous areas where I do notice the TC engaging.

mt_goat

I'm thinking that the malfunction would be that your TC is not locking up and is just constantly slipping at high speeds, it wouldn't have to be going in and out, it could just stay in that slipping mode and that would generate lots of heat.