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Transmission Temperature too high?

19K views 26 replies 11 participants last post by  weareweird69 
#1 ·
Hey guys, Ive got a good question...

1995 Powerstroke, E4OD.

Before the Torque Converter Died on me over a month ago, my Tranny temp wouldn't climb higher than 150-160* F during normal driving, highway, and some in town.

The Day it died, it was around 180-190* F on a 32* F day

I got it rebuilt, Racer X rebuild kit with extra clutches, intermediate band, and a triple disk Torque Converter, along with a Trans Go Tugger kit, with pump mod.

Now, today, its 55-60* F outside, and I was driving it on some back roads, not real bad as far as hills and windy, and my Tranny Temp was around 190* F

Is that normal, or ok? I have probably only about 100-200 miles on the rebuild as of now, and REALLY dont wanna sink more cash into it if it breaks again.

I flushed the Cooler and lines as well before the trans was installed again.

All of the above driving, was Empty driving. Unladen weight of my truck is about 7000 lbs.

Any help is appreciated, I planned on putting a new cooler in sometime for more capacity.

Thanks,
Garrett
 
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#4 · (Edited)
You have to replace the whole Radiator to do that dont you?

And, I had flushed the lines fairly well, I really didnt want to get into the cooler stuff, at least NOW... but I may have to.

Anything else that would cause this?

Also, the trans fluid was clean when it came out, no chunks, or shavings, even out of the TC.


I am starting to think its the gauge however, because it gets hot fast, 4 miles = 150* possible that the sender got screwed up during the transmission change, or there may be a pocket of air in there?

I am trying to exhaust all my free options before I do cooler mods.

but, If I end up doing cooler mods, obviously an upgrade is the thing to do, but which way to go?




EDIT:

How can I check to see if any of the coolers are restricted?
 
#5 ·
your trans temp is not bad, i would not want to see much more than thatmaybe 230-250ish max. but when the cooler goes through the radiator it will either cool or heat the trans fluid to engine temp. so if the tranny fluid is cold the radiator will heat it to engine temp. what you can do is route the fluid through the radiator cooler 1st. then through external cooler last. that should keep fluid temp fairly low. anyway where did you mount the temp sensor.
 
#16 ·
but when the cooler goes through the radiator it will either cool or heat the trans fluid to engine temp. so if the tranny fluid is cold the radiator will heat it to engine temp.
That's a common misconception. The radiator cooler ALWAYS cools the ATF. I've tested this extensively from -40F ambient to +115F ambient. I never found a condition where the radiator warmed the trans fluid. The radiator cooler is in the cold side of the radiator, and that temp is A LOT colder than the hot side.
 
#6 ·
TRANNY TEMPS:


Alot of people freak out for no reason,...







Most automatic transmissions fail due to a breakdown of the transmission fluid caused by overheating. This chart provides a graphic display of heats contribution to transmission failure. The effect is also cumulative. Short term exposure to high heat levels (or even prolonged exposure to moderate heat) can break down the fluid to the point where even very short episodes of overheating will lead to failure.
 
#7 ·
Since the radiator cooler requires replacement of the entire radiator and those are far from cheap I opted to place a filter with a pressure bypass (if it gets completely clogged) after the radiator cooler but before the oversized auxiliary cooler.

I can say that for the first thousand miles my temps were a bit warmer than they had been before and then they settled down to be far cooler that pre-rebuild.

It is possible that you have a failed trans temp sender but an air pocket is very unlikely.
 
#8 ·
Tank, I saw your post before on trans temps. Just my trans never climbed much over 150*, and 160-170* towing Pre-rebuild. I was just very worried the other day that it climbed over 200*

4-play, the sender is in the pressure port, on the drivers side of the trans, above the pan.

I also think the sender is bonkers. In 2 miles, it climbs to over 110*, and after idling for 15 minutes, the needle on the gauge is off its stop post.

I may just leave it be like BJS said, and see if it settles down after bit.


Thanks guys, and any more input will be helpful.
 
#9 ·
dont listen to 4-play.

your tranny should be running 100 degrees over ambient.

so if its 50* out , 150* is normal.

temperatures over 200 arent normal for every day driving.

if you run that tranny 230*-250* like 4-play said.... you are going to be replacing that tranny again real soon.

make sure the bypass is functioning properly, and make sure the cooler isnt backed up.

before u do that,, change ur tranny sender and gauge.
 
#10 ·
I spoke with Racer X today, and was told that the transmission will run warmer with tighter clearances, and being that i have extra clutches, they are still wearing in, and generating heat. It only has 200 miles on the transmission. and nothing more than a 15 mile trip at a time.
 
#11 ·
i did not say 230-250 is "normal" and i wouldnt want to see that as being normal, but if towing heavy with a stock cooler system you will find that temp to be normal briefly. the cooler that runs through the radiator will at least try to heat the fluid to engine temp also. i stated 190 is ok and that is normal. i would recommend everyone to get a larger external cooler and external filter. also recommend changing fluid sooner if towing or modded.
 
#12 ·
I am going up to the transmission guy Monday, and we are going to check the trans temp with a gun, and determine if the sender is faulty, and go from there, I will check back in!
 
#13 ·
Hi,
Glad to hear the shop has diagnostic equipment. :)

If you purchased both kits and converter bear in mind your geartrain is now heavier than stock, all parts are new, and you have more surfaces than OEM. Our kit materials are also higher quality than OEM grade materials.

Most owners didn't have tranny temp gauges to monitor when the truck was all new either. :)

Not sure if any of the OEM's agree with the temp chart or if it dates back to type F fluid or earlier. Various charts have existed as long as automatic transmissions have.

The pcm monitors transmission temperature and uses it for shift strategies. It will flash the OD light on your shifter if temperature reaches Ford's definition of overheat. Check with your tuner on this if you have a chip/tuner installed.
Please contact us if you or the shop need help. Thanks.

.
 
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#14 ·
my isspro gauge was out of whack for a bit, sometimes running hotter than it could be, sometimes all over the place. i see you have autometers but i imagine they work the same. changed out the amp box and sending unit three times (free from isspro via diesel manor) as i was trying to avoid taking off the pillar. finally changed everything and it turned out it was in the gauge
 
#18 ·
keep in mind the charts are for fluid life, and at least for oem trans and coolers they can see temps above 200. the e40d's are even notorius for getting hot enough to cause front seals to puke fluid when towing heavy. this is why we should all change our trans fluid at the very least every 30k and add a larger external cooler. and yes the radiator can and will heat trans fluid depending are the temp differential, an overheating engine can cause trans fluid to overheat too.
 
#19 ·
Well, The gauge isnt lieing...

The transmission where the sender is reads 158* when my gauge reads ~160*

The transmission PAN reads 97*

Needless to say. I am going to be removing the tranny lines, old cooler, and bypassing the radiator cooler, while installing larger transmission lines, bypass for the lines, and installing a larger cooler.

Granted the heat range is acceptable, but not good enough for me. Ill keep everyone informed on what happens.
 
#20 ·
good deal, hope you get it cooled down, the factory cooler set ups are only marginal for what should be expected. keep in mind you replacing 2-coolers with one. so go big. deleting the radiator cooler can sometimes help an engine run cooler too.
 
#22 ·
Got a kit coming.

Comes with a Cooler Bypass, larger lines, larger fittings in transmission, deletes radiator cooler, and adds a larger aux. cooler.

Should be here in a few days. :)
 
#23 ·
97 degrees on the pan & 50+ degrees warmer @ the sender is a good clue. Any hot exhaust fluid from the clutch surfaces mixes with fluid thats returned from the cooler to the pan. The mix temp in the pan is the overall operating temperature the PCM monitors.

I was hoping for pressure readings with temp readings.
Clutches are end users including converter clutches. Apply them with enough pressure to hold tight and heat is minimal. Sliding or slowly applying clutches from pressure drops or other causes etc, will make heat like a dragging brake pad. They're some of the 202 cataloged parts that must all be fitted correctly. :)

LOL We can make hydraulic hoses in house into cooler line when requested. With inner steel braid made to hold 5000 psi it's much more than needed for cooler line. :usflag They're not as pretty when compared to fiber reinforced hose with outer stainless braid. :)

The OE based converters available out there can wreak cooler havoc & more if the design fails in the worse way possible. :damnit

3 different levels of "Hot" clutch failure caused by slippage from different causes in different transmissions. Warp from heat is left. Extreme warp is right, metal has reshaped enough to be stuck tightly to the drum. Bluing has marked the steel both left & right.


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#24 ·
The Temp difference is a clue as to?


And, wow was I glad ive never seen a torque converter like that! AND, my friend who just ordered clutches from you (Racer X) just destroyed his 2nd gear clutches some how. They looked like the clutches on the left. NO clutch material left on the clutch, and warped the steel and clutch.


Also, the shop/guy that built my transmission, is known for making tolerances a little bit tight. So I am sure that isnt helping the temp any. But, after the new cooler mods then it should be good for a long time, if not, I will drive it and see if it continues to cool down as it "wears in"
 
#27 ·
Well, the guy that had built my transmission WAS a highly recognized Ford Tech, and actually started their "Trans Drive" Transmission shop that the Ford Dealership still uses today. I am unclear as to the seperation, i think that it was a conflict of interests, and/or pay issues.

But Either way, he has always had an answer, and a solution for me, and not once has let me down.

But, thankfully I found someone that can answer my questions, and sit down with me and shoot the breeze and listen to my questions and my gripes.

But, we came to the conclusion that the clutches were not at fault, and are almost positive its in the lines/coolers.

But I will say this

Racer X has fantastic customer service!
 
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