Hello, I have a truck with a th400 and a larger transmission cooler and temp gauge. I have the gauge hooked up to the output side of the trans so i can read the max temps of the oil. I live in ny and it has been -10f -> 40f throughout the winter season. My trans never gets above 100f even after driving my 20 mile commute. It will only get to 200f when plowing and i have not plowed in a while. I am wondering if i will get water build up in the trans because the oil is not getting hot enough to evaporate it?
atf temp too cold?
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Water in oil is from combustion in an engine.Unless water got into oil filler tube,or some other way, there shouldn't be any water in oil. It's hydraulic only.
Originally Posted By: daves66nova
Water in oil is from combustion in an engine.Unless water got into oil filler tube,or some other way, there shouldn't be any water in oil. It's hydraulic only.
Water gets into hydraulic over the years through condensation.
Water in oil is from combustion in an engine.Unless water got into oil filler tube,or some other way, there shouldn't be any water in oil. It's hydraulic only.
Water gets into hydraulic over the years through condensation.
Put a thermostat in the tranny lines. I use this one from someone who i know personally, he builds them right here in MA from the finest materials, these are hand built and individually tested. Its the best in the business.
I tested it extensively with the scan tool in winter and summer temps and it allows the tranny to warm up nice in winter and cool in the summer.
http://www.makcotransmissionparts.com/708-4921.html
This is his company.
http://thermostasis.com/
I tested it extensively with the scan tool in winter and summer temps and it allows the tranny to warm up nice in winter and cool in the summer.
http://www.makcotransmissionparts.com/708-4921.html
This is his company.
http://thermostasis.com/
I'm not a tranny expert, but I have stayed at a Holiday Inn......
The thermostat set up seems to make sense from my reading over the years. Lets things get up to temp. Too much cooler etc leads to over cooling in borderline cool temps, not to mention freezing temps.
The thermostat set up seems to make sense from my reading over the years. Lets things get up to temp. Too much cooler etc leads to over cooling in borderline cool temps, not to mention freezing temps.
Originally Posted By: oilboy123
I'm not a tranny expert, but I have stayed at a Holiday Inn......
Thanks pal i just spit my coffee all over my screen.
Yes, my GP has a large aftermarket cooler with a high stall converter, last year it was 17f but clear and dry so i drove it.
Tranny temp wouldn't get over 116f no matter how far i drove it. With the thermostat 168f after a few miles then it opened and maintained that temp to within a few degrees.
In summer its wide open after a short time but the tranny gets to operating temp quicker. Nice!
I'm not a tranny expert, but I have stayed at a Holiday Inn......
Yes, my GP has a large aftermarket cooler with a high stall converter, last year it was 17f but clear and dry so i drove it.
Tranny temp wouldn't get over 116f no matter how far i drove it. With the thermostat 168f after a few miles then it opened and maintained that temp to within a few degrees.
In summer its wide open after a short time but the tranny gets to operating temp quicker. Nice!
Might be a good time to do a drain and fill while you're thinking about the transmission.
I monitor the trans temp in my E450 with a ScanGuage II and yesterday's ambient temps around +10F, the tranny peaked at 160. It took about 50 miles of driving to stabilize.
Summertime temps are 180 and the most I've seen climbing hills was 210F. I'm not sure if there's a thermostat in the transmission cooler. Anyone know? 5R110W transmission.
Summertime temps are 180 and the most I've seen climbing hills was 210F. I'm not sure if there's a thermostat in the transmission cooler. Anyone know? 5R110W transmission.
ATF emulsifies water and gets milky. If it looks milky, it has a lot of water in it. I'd block off that cooler in the winter, but otherwise, don't worry. On mine I rigged a ball valve in the hose to the external cooler to bypass it.
Originally Posted By: LotI
I monitor the trans temp in my E450 with a ScanGuage II and yesterday's ambient temps around +10F, the tranny peaked at 160. It took about 50 miles of driving to stabilize.
Summertime temps are 180 and the most I've seen climbing hills was 210F. I'm not sure if there's a thermostat in the transmission cooler. Anyone know? 5R110W transmission.
Many of the Fords do if they have an OE external cooler. Its right in the lines similar to the one i linked to only is flatter.
GM and some other makes have one inside the transmission.
The ones that don't like the one the OP has don't and can really benefit from one.
I monitor the trans temp in my E450 with a ScanGuage II and yesterday's ambient temps around +10F, the tranny peaked at 160. It took about 50 miles of driving to stabilize.
Summertime temps are 180 and the most I've seen climbing hills was 210F. I'm not sure if there's a thermostat in the transmission cooler. Anyone know? 5R110W transmission.
Many of the Fords do if they have an OE external cooler. Its right in the lines similar to the one i linked to only is flatter.
GM and some other makes have one inside the transmission.
The ones that don't like the one the OP has don't and can really benefit from one.
Originally Posted By: oilboy123
I'm not a tranny expert, but I have stayed at a Holiday Inn......
Quote of the year!
I'm not a tranny expert, but I have stayed at a Holiday Inn......
What type of cooler do you have? An older tube-and-fin type cooler will cool the fluid at all times, even if its -10F out. A more modern plate style cooler has an internal "thermostat" that will bypass the cooling section until the fluid gets to some minimum temperature.
Plate style coolers are usually a bit more expensive but worth it, especially in areas that see such a wide temperature swing between winter and summer.
I'd say bypass the cooler in the winter months, but since you plow it would be a good idea to leave it on.
Plate style coolers are usually a bit more expensive but worth it, especially in areas that see such a wide temperature swing between winter and summer.
I'd say bypass the cooler in the winter months, but since you plow it would be a good idea to leave it on.
What is the ideal operating temperature range for an automatic transmission?. In particular for the transmissions on my '87 Olds 88 and '89 Buick LeSabre.
I live in the Uk so get nothing like the ambient temperature swings like a lot of North America. 25f-95f is about as much as it gets for me.
I have put tube and fin coolers on them as I haul a 1700lb trailerhome with them, this on the advice of my local highly reputable transmission guy.
I know an overheating transmission will fail very quickly, but how much damage will running cold do?.
Incidentally, I have been told that the cooler lines only have much flow when the converter is locked. This seems illogical to me, surely most heat is generated when the converter is slipping?.
Any gurus here willing to enlighten me please?.
Claud.
I live in the Uk so get nothing like the ambient temperature swings like a lot of North America. 25f-95f is about as much as it gets for me.
I have put tube and fin coolers on them as I haul a 1700lb trailerhome with them, this on the advice of my local highly reputable transmission guy.
I know an overheating transmission will fail very quickly, but how much damage will running cold do?.
Incidentally, I have been told that the cooler lines only have much flow when the converter is locked. This seems illogical to me, surely most heat is generated when the converter is slipping?.
Any gurus here willing to enlighten me please?.
Claud.
Originally Posted By: Claud
What is the ideal operating temperature range for an automatic transmission?. In particular for the transmissions on my '87 Olds 88 and '89 Buick LeSabre.
I live in the Uk so get nothing like the ambient temperature swings like a lot of North America. 25f-95f is about as much as it gets for me.
I have put tube and fin coolers on them as I haul a 1700lb trailerhome with them, this on the advice of my local highly reputable transmission guy.
I know an overheating transmission will fail very quickly, but how much damage will running cold do?.
Incidentally, I have been told that the cooler lines only have much flow when the converter is locked. This seems illogical to me, surely most heat is generated when the converter is slipping?.
Any gurus here willing to enlighten me please?.
Claud.
I can't answer this directly, but just from my experience with my van and trailer. One of my first vehicle upgrades to the van after getting the trailer was to install a transmission temperature gauge. The point at which I had the temperature sender mounted was in the transmission line, just as it came out of the transmission, and before the vehicle's radiator (which supposedly had an upgraded radiator with an integrated cooler for towing). I chose this location as I figure it should be the fluid at its hottest point in the system, and will therefore be a good early warning for high temperatures. The vehicle is a 2006 Toyota Sienna, FWD, Aisin 5 speed auto.
When NOT towing, here were my observations on temperature:
Ambient temperature, vehicle speed and whether the air conditioner was on or not were the three primary factors in the running temperature of the transmission:
- Ambient temperature around 70F, no air conditioner: with stop and go driving, about 190F, in town not stop and go, about 160 to 170, and highway as low as 130F.
- Ambient temperature around 90F with the air conditioner: stop and go around 215F, in town not stop and go, about 180F, and highway between 140 to 150F.
- Ambient temperature around -5F, possibly air conditioner kicking in and out for windshield defog mode: stop and go driving, may be lucky to touch 110F, in town not stop and go, maybe 90F, and highway maybe 60F if lucky.
Towing has the effect of greatly increasing most of these temperatures, especially under extreme conditions: mountains, high ambient temperature and A/C, I've had times where I near 240F, before I make a decision to pull over and let it cool down before proceeding. It would have certainly continued to climb had I not stopped.
I added an external passive transmission cooler shortly after, and under all conditions, it has lowered temperatures, from significantly (while in motion), to minimally (stationary or very low speed).
So, my transmission going through all that, including not getting warm in the winter has held up just fine and is showing no signs of deterioration, other than maybe minor "looseness" which could be attributed to it's age. It is 9 years old, with over 130,000 miles, and has seem summer towing duty since about the 3 year old / 40,000 mile mark. It has always seen an annual drain and fill since it entered towing duty.
That said, I have also heard of some auto trannies not being fond of the cold, like some on certain Mitsubishi models.
What is the ideal operating temperature range for an automatic transmission?. In particular for the transmissions on my '87 Olds 88 and '89 Buick LeSabre.
I live in the Uk so get nothing like the ambient temperature swings like a lot of North America. 25f-95f is about as much as it gets for me.
I have put tube and fin coolers on them as I haul a 1700lb trailerhome with them, this on the advice of my local highly reputable transmission guy.
I know an overheating transmission will fail very quickly, but how much damage will running cold do?.
Incidentally, I have been told that the cooler lines only have much flow when the converter is locked. This seems illogical to me, surely most heat is generated when the converter is slipping?.
Any gurus here willing to enlighten me please?.
Claud.
I can't answer this directly, but just from my experience with my van and trailer. One of my first vehicle upgrades to the van after getting the trailer was to install a transmission temperature gauge. The point at which I had the temperature sender mounted was in the transmission line, just as it came out of the transmission, and before the vehicle's radiator (which supposedly had an upgraded radiator with an integrated cooler for towing). I chose this location as I figure it should be the fluid at its hottest point in the system, and will therefore be a good early warning for high temperatures. The vehicle is a 2006 Toyota Sienna, FWD, Aisin 5 speed auto.
When NOT towing, here were my observations on temperature:
Ambient temperature, vehicle speed and whether the air conditioner was on or not were the three primary factors in the running temperature of the transmission:
- Ambient temperature around 70F, no air conditioner: with stop and go driving, about 190F, in town not stop and go, about 160 to 170, and highway as low as 130F.
- Ambient temperature around 90F with the air conditioner: stop and go around 215F, in town not stop and go, about 180F, and highway between 140 to 150F.
- Ambient temperature around -5F, possibly air conditioner kicking in and out for windshield defog mode: stop and go driving, may be lucky to touch 110F, in town not stop and go, maybe 90F, and highway maybe 60F if lucky.
Towing has the effect of greatly increasing most of these temperatures, especially under extreme conditions: mountains, high ambient temperature and A/C, I've had times where I near 240F, before I make a decision to pull over and let it cool down before proceeding. It would have certainly continued to climb had I not stopped.
I added an external passive transmission cooler shortly after, and under all conditions, it has lowered temperatures, from significantly (while in motion), to minimally (stationary or very low speed).
So, my transmission going through all that, including not getting warm in the winter has held up just fine and is showing no signs of deterioration, other than maybe minor "looseness" which could be attributed to it's age. It is 9 years old, with over 130,000 miles, and has seem summer towing duty since about the 3 year old / 40,000 mile mark. It has always seen an annual drain and fill since it entered towing duty.
That said, I have also heard of some auto trannies not being fond of the cold, like some on certain Mitsubishi models.
Originally Posted By: Claud
What is the ideal operating temperature range for an automatic transmission?. In particular for the transmissions on my '87 Olds 88 and '89 Buick LeSabre.
I live in the Uk so get nothing like the ambient temperature swings like a lot of North America. 25f-95f is about as much as it gets for me.
I have put tube and fin coolers on them as I haul a 1700lb trailerhome with them, this on the advice of my local highly reputable transmission guy.
I know an overheating transmission will fail very quickly, but how much damage will running cold do?.
Incidentally, I have been told that the cooler lines only have much flow when the converter is locked. This seems illogical to me, surely most heat is generated when the converter is slipping?.
Any gurus here willing to enlighten me please?.
Claud.
I'm no guru just an old wrench turner but here is my take on it.
165-170f is optimal for most automatics. You are correct most of the heat generated is from the torque converter slippage, afaik on GM transmissions it goes though the cooler full flow all the time when the engine is running regardless of gear selection.
The cooling circuit is relatively low pressure and high flow.
Running them cold adds some additional wear, they are designed with clearances that are optimal at operating temperature. For this very reason many newer units have a thermostat built into the transmission or in the lines like on some Fords.
It allows the unit to obtain operation temperature faster, reducing wear.
Synthetic fluid are superior at higher temperatures and definitely has advantages especially in a vehicle use for towing. periodic temps of 200-220f are no problem for the fluid, and should not generate any additional wear on the unit.
In the UK climate i wouldn't worry about it, it doesn't get cold enough to warrant a thermostat unless you bypassed the radiator cooler or are running the aftermarket cooler after the radiator cooler (better for towing).
The radiator cooler is also a fluid warmer in cold temps.
What is the ideal operating temperature range for an automatic transmission?. In particular for the transmissions on my '87 Olds 88 and '89 Buick LeSabre.
I live in the Uk so get nothing like the ambient temperature swings like a lot of North America. 25f-95f is about as much as it gets for me.
I have put tube and fin coolers on them as I haul a 1700lb trailerhome with them, this on the advice of my local highly reputable transmission guy.
I know an overheating transmission will fail very quickly, but how much damage will running cold do?.
Incidentally, I have been told that the cooler lines only have much flow when the converter is locked. This seems illogical to me, surely most heat is generated when the converter is slipping?.
Any gurus here willing to enlighten me please?.
Claud.
I'm no guru just an old wrench turner but here is my take on it.
165-170f is optimal for most automatics. You are correct most of the heat generated is from the torque converter slippage, afaik on GM transmissions it goes though the cooler full flow all the time when the engine is running regardless of gear selection.
The cooling circuit is relatively low pressure and high flow.
Running them cold adds some additional wear, they are designed with clearances that are optimal at operating temperature. For this very reason many newer units have a thermostat built into the transmission or in the lines like on some Fords.
It allows the unit to obtain operation temperature faster, reducing wear.
Synthetic fluid are superior at higher temperatures and definitely has advantages especially in a vehicle use for towing. periodic temps of 200-220f are no problem for the fluid, and should not generate any additional wear on the unit.
In the UK climate i wouldn't worry about it, it doesn't get cold enough to warrant a thermostat unless you bypassed the radiator cooler or are running the aftermarket cooler after the radiator cooler (better for towing).
The radiator cooler is also a fluid warmer in cold temps.
Thanks, Trav & Weebl.
I plumbed in the cooler to run through the coolant radiator after the aftermarket one, again on the advice of my local automatic transmission guy.
For the low miles I put on it I guess I'll just leave it as it is.
It mostly travels to car shows in the warmer months, with the trailerhome on the back if my wife comes along. Then it will be mostly cruised around the showground at walking pace.
Claud.
I plumbed in the cooler to run through the coolant radiator after the aftermarket one, again on the advice of my local automatic transmission guy.
For the low miles I put on it I guess I'll just leave it as it is.
It mostly travels to car shows in the warmer months, with the trailerhome on the back if my wife comes along. Then it will be mostly cruised around the showground at walking pace.
Claud.
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