quicksilvr
New member
I couldn't answer that exactly. I'm not sure how the lock-up clutch behaves at different speeds and in different gears. Maybe someone else knows....?
Auto Trans operating Temps
- Thread starter SIKHILUXSURF
- Start date
I couldn't answer that exactly. I'm not sure how the lock-up clutch behaves at different speeds and in different gears. Maybe someone else knows....?
O/D button is for the overdrive gear. In 2nd, it has no impact. I've observed that the torque converter will only lock up when acceleration has stopped and you are cruising. Not sure about decelerating though.
Qyota
New member
What about adding a push fan instead? Then, just don't run it in the winter. Flip the switch (or have it thermo-controlled) in the summer when towing. I have no idea how effective it would be, but it would probably be less work that constantly adding in and removing a second cooler.
quicksilvr
New member
My current cooler is sandwiched between the condenser and the radiator. There's not really a good way to put a fan on it. However, I do like it there, because it gets good air from the the radiator fan for slow speed and in town. It's a 70268, so it's just too small for high ambient temps and towing all by itself. I'm going to add a second one and plumb it so it's easy to bypass. Only have to mess with it twice a year, and it shouldn't take more than 10 minutes.
AddictedOffroad
New member
Bands will stretch and begin to breakdown. You basically had the tranny boiling, which will breakdown the fluid as well.
You did the right thing by replacing the fluid. And, until you have an issue i wouldn't worry about it, but don't ever let it get that hot again.
Qyota
New member
Please be sure to document this project here - as it might be something I do as well. :cheers:
turbodudey2
New member
Actually more like 30 seconds to change. If you do it like this:
Attachments
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quicksilvr
New member
Thanks for the drawing franky.
I don't suppose you have any specific valves in mind for that job do you?
I was planning on doing what you drew....except instead of valves, just having two couplers, and having some loose hose ends to cap off when not in use. Basically install the second cooler, run both of the second cooler lines to that spot on the first cooler's "out" line, and simply unhook it and zip tie the lines out of the way when not in use.
But valves would be sweet...if they were a good design that didn't limit flow....
I don't suppose you have any specific valves in mind for that job do you?
I was planning on doing what you drew....except instead of valves, just having two couplers, and having some loose hose ends to cap off when not in use. Basically install the second cooler, run both of the second cooler lines to that spot on the first cooler's "out" line, and simply unhook it and zip tie the lines out of the way when not in use.
But valves would be sweet...if they were a good design that didn't limit flow....
turbodudey2
New member
Some standard 3/8" full port ball valves would work. Something like this:
Ball Valve
Could be found at your local Lowe's, Home Depot, Ace Hardware, etc.
Or if you wanted to get real fancy you could use a three-way mixing valve in place of valves 1 & 3 in the above drawing.
3-Way Valve
The 3-way valve would have the same functionality as two separate valves, in that you could switch between using one cooler or both. Here comes the fun part - you could also set it to get partial flow to both ports. Then you'd have the cooling capacity of 1.5 coolers. (for the spring and fall when it's not or or cold outside)
quicksilvr
New member
Some standard 3/8" full port ball valves would work. Something like this:
Ball Valve
Could be found at your local Lowe's, Home Depot, Ace Hardware, etc.
Or if you wanted to get real fancy you could use a three-way mixing valve in place of valves 1 & 3 in the above drawing.
3-Way Valve
The 3-way valve would have the same functionality as two separate valves, in that you could switch between using one cooler or both. Here comes the fun part - you could also set it to get partial flow to both ports. Then you'd have the cooling capacity of 1.5 coolers. (for the spring and fall when it's not or or cold outside)
Ha. The 3-way is a bit over kill I would think. Honestly, if I never towed anything, I'd be fine without even adding a 2nd cooler, although I am attracted to the two cooler idea for summer just to keep me average temps down. I like 150 (what I'm guessing I'll get with two coolers in play) alot more than 190 for constant in town driving....
According to the '99 FSM-
pg. DI-324 Until the coolant (antifreeze, not ATF) temperature reaches 60C (140F) both the torque converter lock-up and overdrive (4th) gear are prohibited. Once the coolant warms up those will both work normally.
pg. SS-53 5VZ-FE 4wd Lock-up point at 5% throttle,
O/D gear, (NORM and PWR)
lockup on @45-48mph
lockup off @40-44mph
Slightly different speeds are given for 2wd and 4cyl. No listing is given for 3rd gear although I believe the torque converter will also lock up in that gear. It will not lock up in 2nd gear (pg DI-324).
pg. DI-324 Normal operating ATF temperature listed as 50-80C (122-176F)
pg DI-325, 326 Normal operating fluid temperature for checking ATF fluid level listed as 70-80C (158-176F).
Operating temperatures shown at even numbers (50, 70, 80) are probably selected as a "close or thereabouts" number. I wouldn't take them as strictly exact. A number of other pages show the normal operating temperature as 50-80C for functional tests. Interesting that the fluid level is checked at such a narrow range. How would Joe Schmoe know the ATF temperature?
So for you folks running in cold temperatures with an external cooler, anything below ~120F is below normal operating temperature. I'm guessing as long as the tranny is shifting normally at subnormal temperatures, you're ok.
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Now that is some freaking awesome info to have and know.
AddictedOffroad
New member
So, I just got off the phone with BigJohn. He ran down to Denver to grab a Scan Gauge II off of a guy on a local board.
He runs no external tranny cooler. He called me before coming back, and I gave him the code for the A/T temp. He input it while idling for several minutes. Outside temps are around 45*. His tranny at idle was about 145*. Then after a few miles on the fwy it was at 135* and holding steady at 75mph.
So, considering that mine with just the large external cooler runs pretty much at the same temps I would say that its not much different for everyday use than with the stock cooler. It definitely doesn't run warmer just because it goes into the radiator. That is for sure.
He runs no external tranny cooler. He called me before coming back, and I gave him the code for the A/T temp. He input it while idling for several minutes. Outside temps are around 45*. His tranny at idle was about 145*. Then after a few miles on the fwy it was at 135* and holding steady at 75mph.
So, considering that mine with just the large external cooler runs pretty much at the same temps I would say that its not much different for everyday use than with the stock cooler. It definitely doesn't run warmer just because it goes into the radiator. That is for sure.
quicksilvr
New member
Yeah, that's about what I figured, based on some numbers posted by users over on yotatech. It's the warming up after being completely cold that the radiator cooler helps with. BigJohn had been driving around town already when you hooked the SGII in. Trans was already warm.
Do a little research, and have him keep the SGII on his rig for a couple days. On a cold start, let the engine idle long enough for the coolant to hit 180ish. See where the ATF is after doing nothing but idling with the engine warm and thermostat open. Then see what the ATF does if he starts driving, and goes right to highway speed....like only 1 full start from a stop right into cruising.
Then do the same thing with yours. This should be a nice little comparo!
quicksilvr
New member
DontKnowRunner
Member
Verdict on external coolers and low temps - vs stock setup?
I read this thread with great anticipation. It appeared as if we were close to getting some data to understand the impact of a sole external cooler on the ATF temps in cold weather, and then nothing. Was there an off-forum consensus reached on any negative impact the external cooler had in cold weather driving, or if it was better just to replace the radiator and run the stock setup?
I was all set to go forward with an external cooler only, but after reading this, I'm concerned about impact of the cold on the tranny in certain conditions. How's your tranny QuikSilver? Anyone else have any more info on this?
I read this thread with great anticipation. It appeared as if we were close to getting some data to understand the impact of a sole external cooler on the ATF temps in cold weather, and then nothing. Was there an off-forum consensus reached on any negative impact the external cooler had in cold weather driving, or if it was better just to replace the radiator and run the stock setup?
I was all set to go forward with an external cooler only, but after reading this, I'm concerned about impact of the cold on the tranny in certain conditions. How's your tranny QuikSilver? Anyone else have any more info on this?
There's nothing wrong with the cooler in the radiator. Manufacturers have been doing it for years with great success. Only real reason to do it is avoiding the radiator breaking and flooding the transmission with coolant. Otherwise it's just another one of those warm and fuzzy mods.
PhdNPrerunners
New member
Hey guys on Saturday I installed a tru cool 4590 and bypass the stock radiator to prevent the pink milkshake. Today as I was driving around I saw temps in the 110-150 range. Would you guys say those are too low or I am just worrying too much?
