quicksilvr

SGII will not read an ATF temperature on 96-98 4runners. 99-on it will.

That above code is correct, and works on every Toyota/Lexus vehicle I've hooked up to. That x-gauge code for ATF temp worked on 99 4runner, 01 RAV4, 01 Landcruiser and 02 4runner. So I would say any Toyota/Lexus vehicle with a trans temp output to OBDII should utilize that code.



Also, for more detailed discussion on the "ATF temperature" issue, just read the big honking "Bypass the OE tranny cooler?" thread. Lots of discussion and info in there.

spokane.yota.man

Has there been any discussion on whether the red vs green antifreeze debate plays into this topic as well? Maybe one or the other accelerates the issue? Any victims want to share their antifreeze type at the time of failure?

badattitude

I was using Toyota Red coolant when I had the milkshake at 116,000. Radiator/Trans cooler failure occured 30,000 miles after coolant flush.

maxspeed96ct

I have a b&m trans cooler waiting to be installed, just waiting for some kind of heat wave in this new england winter.

Some say the external trans cooler isnt good, because on very cold days the atf fluid needs the radiator to bring the fluid to a good operating temp. But this just means with a external cooler you should wait a extra few minutes before poping into drive on very cold days.

I paid about 60$ on amazon, came with everything needed. Though I think im going to run new 3/8 lines from the trans up to the cooler .


http://www.amazon.com/gp/product/B00...ef=oss_product

spokane.yota.man

Maxspeed96ct, let us know how the install goes. I've got a new koyo radiator in the mail. I think all these milkshake posts is really boosting the business for aftermarket radiators and coolers. I'm going to stick with rad only unless I start towing more then I'll install external cooler.

Thanks badattitude. That's one failure for red, hopefully more people share and this thread gets some good data.

SkidPalace

That link says $49.99 shipped right now. Decent price.

maxspeed96ct

ya i think with shipping it came out to just under 60.

Ill be sure to post up some pics when I install it.

J2F42C

https://www.yotatech.com/forums/f2/t...esults-200965/

Good read....

Qyota

My truck's been bypassed for about a year now. I think I'll be going back to the in-radiator cooler. Actually, I think I'll do an inline external cooler setup with valves for the winter. Some cold days my ATF doesn't get above 80F. And while I think my transmission is fine, I know the fluid should be hotter than that for optimal lubrication. Running the ATF through the radiator should help warm it up faster in the really cold months. Then, when the weather is warm, open the valves to the external cooler and get the best of both worlds.

I realize this puts me back in the "milkshake" potential...but with a brand new radiator I won't have to worry about that for several years. And at $100 apiece...a new radiator is cheap insurance.

I used to beat the "bypass only" drum...but this cold ass winter has me changing my mind.

maxspeed96ct

Man this is exactly what I was worried about. 80 is to low, what are you using to monitor ? Are you sure its acurate?

I'm glad you shared this, because it means I'm going to be buying a new radiator when I install my cooler. And I won't bypass the rad.

Qyota

Scangauge2. I think it's pretty accurate, but how would I know for sure?

Also, when towing a small trailer (pop-up camper) this past summer, with the cooler installed (bypassed radiator), I saw temps nearing 220. I just don't think it can do a good job keeping the ATF in the optimal range like the in-radiator setup can.

maxspeed96ct

Ya I bet the scan gauge is accurate. I'm glad you posted . Because I was affraid of that happening living in CT. But was going to find out for myself.

Qyota

I don't think it's anything to be too concerned about. Like I said, I can't say that I know I've done damage to the transmission. I'm just not terribly comfortable with the low temps of the fluid on cold days. It still goes into reverse and drive just fine, even with ATF in the low 20's or upper teens. Again, these are scangaugeII numbers, on very cold days. Once the fluid does finally warm up (in town driving), it seems to be less affected by the cold, and will float around in the 130's-140's.

But I've noticed that if the outside air temp is above freezing, the ATF warms up significantly faster. So, really I see the cold temps being a problem 3 months out of the year...where I live at least.

maxspeed96ct

Ya I was -5 outside when I woke up this morning...
So Its a concern for me, and I havent been able to get a straight answer so once again im glad you shared your readings . If you let the truck idle on a below freezing day. How long does it take for the fluid to reach 80 ?

Qyota

I don't let the truck idle for more than a minute or two - even on very cold days. It's faster and more efficient to just drive slowly for a few minutes. Idling in the driveway does little to warm up the transmission. It has to be in gear, and changing gears to really warm up.

Depending on where I'm driving (highway or in town), it takes longer to warm up. Once it's in O/D on the highway, it basically stays at 60-80 degrees until I slow down and get into town. However, if I do more in-town driving initially, it'll warm up to ~100, then climb slowly from there.

The external cooler is extremely efficient in sub-freezing temps, but not nearly as efficient when it's hot out (70+). At least, that's been my experience.

quicksilvr

Interesting Qyota.

My experience differs, so I'll share. I live in town, so most of the time, I let the truck idle for a minute or two, and then start driving. I have at least 3 stop and goes before I can get anywhere, so even when it's below 0, my trans hits 120-130 easily. And that is by the time the coolant is just getting to 180.


Now, here's a different example. At my folks place for thanksgiving. 5 degrees out, and I have a 1 year old that is going into the car sleeping. So I let the truck idle for a good 10 minutes. We get in, coolant is 185. Trans is 60. Slow start downhill on a gravel road and then a little uphill. Get on the highway, and I have one good acceleration up to 65mph. Trans peaks at 115, and then dropped to 97. It slowly over the course of 20 miles inched from 97 up to 112.

That was the type situation where the transmission was doing the least work it could have possibly done, ambient temps were close to 0, and it still was over 100 degree most of the time.

gdutch

I don't have a Scangauge to keep track of my temps, but I never experience hard shifts with my bypassed setup unless it's in the 20's or lower. Living in Texas this is hardly ever a problem, and I'd rather have it completely bypassed for when it's 110 and I'm in gridlock with the AC blasting. Besides, if it's really cold I just put it in 2nd until my engine coolant needle starts to climb.

Qyota

That sounds pretty close, but a bit faster to warm up than mine.

So, you're comfortable with 100-110F ATF during very cold days? It would be great to get a bunch of baseline data of ATF temps using the in-radiator cooler in very cold temps. If the numbers weren't too far off, I'd feel much better.

maxspeed96ct

Thanks for sharing, I normaly let my truck warm up for about 5 minutes if its below freezing out. Unless Im running late.

I always thought trans fluid should be at around 170, I wonder if driving with the fluid at 100 hurts the trans somehow.

Im getting kind of jealous at your scan gauges hehe

quicksilvr

I personally am comfortable with anything 100 or higher for sustained driving. As luck would have it, my good friend is a proud new owner of a '99 Limited. Still using the stock cooler, so I'm going to give him my SGII for a couple weeks here in the winter time, and have him log his ATF temps everyday. We'll see what that yields!

I think in a perfect world, ATF would run a constant 170 degree's, never hotter, never colder. lol However, it's impossible to regulate that precisely, and it is FAR more dangerous to overheat ATF than it is to run it cooler. I know Fogrunner keeps his cool, like 170 max, and has nearly 300K on his stock transmission.