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Pulling my 12,500 pound trackhoe on a 4000 pound trailer I see 185.
Pulling my 14k 5th wheel, I see 200 to 205 on 93 degree days. Is this normal? My 01 runs a little cooler tranny wise. I have the big cooler too, I might add another.
Those temps sound pretty good to me. What cooler do you have?
I would agree as well. Its there, its accurate so leave it where its at. Just know that you may see higher temps than some see with the probe other places. What temps do you see under different conditions?
I have a big camper and a boat, so I can cook it on hot days backing up or pulling a boat ramp. I limit it to 240F max. (The truck is 2WD, so no low range.)
On the highway, the highest it goes is 210F pulling hills. Normal is 160F to 190F. The truck has a huge aftermarket cooler, and the oil to water cooler is in the circuit before the aftermarket cooler.
I'm pretty sure the water cooler is actually heating the tranny when I'm pulling big hills because I had one hill where I sat in D and did 60 MPH for about 20 min at high throttle. No gears are meshing and the TC was locked, so the tranny shouldn't have made heat... but the temp slowly climbed to 210F.
I hesitate to pull it because I suspect the oil to water cooler does help at low speed maneuvering.
I spoke with Mark Kovalsky about this very issue a month or so ago and he said that during all of his tests he found that there is 5-10* difference in multiple locations that he has tested and suggested that the test port on the driver's side is the best location for the temp sensor.
I'm pretty sure the water cooler is actually heating the tranny when I'm pulling big hills
I have a 203F thermostat (vs 195F) and see less than 170F coolant temps @ the bottom of the radiator even after a hard pull. The trans return line measure about the same. Your trans makes a lot of heat even in D with the TC locked. Not sure why, but it does according to my infrared temp sensor.
My trans temps never get higher than 190F, most of the time they are around 170F. I use this as a guide...!
No gears are meshing and the TC was locked, so the tranny shouldn't have made heat... but the temp slowly climbed to 210F.
In an automatic transmission ALL of the gears are meshing ALL of the time. They NEVER come out of mesh.
Having said that, there is no relative motion in the planetary sets when the trans is in 1:1 ratio. I assume that's what you mean when you say it was in D. All those rotating parts can make a HUGE amount of heat if the trans is overfilled by even a little. If the fluid is high enough that the rotating parts are running in it the constant fluid shear will generate a lot of heat.
Originally Posted by joe_13894
I hesitate to pull it because I suspect the oil to water cooler does help at low speed maneuvering.
Yes, it makes a lot of difference in low speed maneuvering. It also takes a lot of heat out of the ATF when the engine and trans are working hard, too. If your trans isn't cooling right you might want to run a flow test on the cooler circuit. A restriction could cause your trans to run hot.
If you are talking about a 1960's trans, then yes, this is fairly accurate. In a modern trans fluid doesn't form varnishes until A LOT over 240F, seals don't harden until well over 320F, I've seen clutch plates NOT slip over the max that the tem gauge reads (340F), and seals and clutches do not burn out at 315F, and fluid does not form carbon at 315F. This chart is used to scare people into buying more cooling than can be justified with an engineering analysis.
If people just like spending $$$ for cooling that doesn't help anything, that's their business. I just don't like spreading falsehoods to make people think it's needed.
Those temps sound pretty good to me. What cooler do you have?
Tis just a std 25k cooler for the local race shop here. I paid 40 bucks for it. the sell quite a few of them. I thought about putting another one inline with this just because..... I would love to see it stay around 160 to 180 when towing all my toys. Occasionally, I put a 20 ft car hauler behind the 36 ft camper that I pull behind the dually. I load the car hauler iwth my Rhino, golf cart, two motorcycles, and some other ni nac stuff. You can see where it comes in handy, but when I drive it in the winter, I would like to se it get above 100 degrees too.......LOL
If you are talking about a 1960's trans, then yes, this is fairly accurate. In a modern trans fluid doesn't form varnishes until A LOT over 240F, seals don't harden until well over 320F, I've seen clutch plates NOT slip over the max that the tem gauge reads (340F), and seals and clutches do not burn out at 315F, and fluid does not form carbon at 315F. This chart is used to scare people into buying more cooling than can be justified with an engineering analysis.
If people just like spending $$$ for cooling that doesn't help anything, that's their business. I just don't like spreading falsehoods to make people think it's needed.
Follow the chart above if you value your $3000 trans...It's easy and less costly to do + Anyone that lets their temps get that hot is asking for trouble.
Yes, it makes a lot of difference in low speed maneuvering. It also takes a lot of heat out of the ATF when the engine and trans are working hard, too. If your trans isn't cooling right you might want to run a flow test on the cooler circuit. A restriction could cause your trans to run hot.
The flow has been checked and it's OK. I don't think I have a "problem"
Pulling hills it generally stays under 210 in the cooler feed line. I can make it hotter maneuvering at low speed - but with 8K on the rear axle of a DRW, it does take a bit of scrub force to corner sharp so I kind of expect some heat moving slow while backing a trailer.
If you are talking about a 1960's trans, then yes, this is fairly accurate. In a modern trans fluid doesn't form varnishes until A LOT over 240F, seals don't harden until well over 320F, I've seen clutch plates NOT slip over the max that the tem gauge reads (340F), and seals and clutches do not burn out at 315F, and fluid does not form carbon at 315F. This chart is used to scare people into buying more cooling than can be justified with an engineering analysis.
If people just like spending $$$ for cooling that doesn't help anything, that's their business. I just don't like spreading falsehoods to make people think it's needed.
Well, I can tell you that 240F killed my factory front seal. But every other seal is still doing fine at 175K.
The factory front seal will fail at even lower than 240. That doesn't make the chart right, it makes the seal a bad design.
And yes, we've been through this before. I still think you and that chart are wrong. I think we will have to agree to disagree about it. But everytime I see it in a post I intend to point out to whoever is listening that it's wrong.
The factory front seal will fail at even lower than 240. That doesn't make the chart right, it makes the seal a bad design.
That was said tongue in cheek... That was the point of stating that the rest of the tranny is just fine.
And yes, we've been through this before. I still think you* and that chart are wrong. I think we will have to agree to disagree about it. But everytime I see it in a post I intend to point out to whoever is listening that it's wrong.
Do you have a better reference to use? I want to do what is "right" and waste money.
* PS don't throw the "you" at me, I didn't put the chart up.
The advice to run a trans hotter than the chart above comes from the very same people that designed the front seal and wimpy trans cooler causing our e4od's to fail prematurely...Says so in his signature anyway.
The advice to run a trans hotter than the chart above comes from the very same people that designed the front seal and wimpy trans cooler causing our e4od's to fail prematurely...Says so in his signature anyway.