203 stat in
Post Fiend
Joined: Oct 2003
Posts: 5,903
Likes: 1
From: MICHIGAN
I personally wouldn't bypass the cooler in the rad. It helps get the trans up to temp quicker, especially if you are running a larger than OEM air to liquid cooler in front of the rad. Too Low temps are just as bad as high. The oil needs to get hot enough to burn off the condensation and get the additive package working + the internal tolerances are designed for certain temps. It's like running an engine with no stat. The oil turns white and foamy from condensation. and shortens the life of the engine.
You can't compare OBS trucks to the Newer ones, they did away with the rad cooler because they have thermostats in their huge air to air cooler system.
Liquid to liquid coolers are much more efficient than an air to liquid. The coolant temp in the radiator very seldom sees the thermostat temp rating. With a 203 stat I doubt you would see 180 temp at trans cooler. I will let you know shortly, a new 203 stat is going in.
My 2 cents
You can't compare OBS trucks to the Newer ones, they did away with the rad cooler because they have thermostats in their huge air to air cooler system.
Liquid to liquid coolers are much more efficient than an air to liquid. The coolant temp in the radiator very seldom sees the thermostat temp rating. With a 203 stat I doubt you would see 180 temp at trans cooler. I will let you know shortly, a new 203 stat is going in.
My 2 cents
Postmaster
Joined: Feb 2004
Posts: 3,266
Likes: 0
From: Levittown
Originally Posted by Cuda_jim
I personally wouldn't bypass the cooler in the rad. It helps get the trans up to temp quicker, especially if you are running a larger than OEM air to liquid cooler in front of the rad. Too Low temps are just as bad as high. The oil needs to get hot enough to burn off the condensation and get the additive package working + the internal tolerances are designed for certain temps. It's like running an engine with no stat. The oil turns white and foamy from condensation. and shortens the life of the engine.
You can't compare OBS trucks to the Newer ones, they did away with the rad cooler because they have thermostats in their huge air to air cooler system.
Liquid to liquid coolers are much more efficient than an air to liquid. The coolant temp in the radiator very seldom sees the thermostat temp rating. With a 203 stat I doubt you would see 180 temp at trans cooler. I will let you know shortly, a new 203 stat is going in.
My 2 cents
You can't compare OBS trucks to the Newer ones, they did away with the rad cooler because they have thermostats in their huge air to air cooler system.
Liquid to liquid coolers are much more efficient than an air to liquid. The coolant temp in the radiator very seldom sees the thermostat temp rating. With a 203 stat I doubt you would see 180 temp at trans cooler. I will let you know shortly, a new 203 stat is going in.
My 2 cents
I agree with you as far as winter use. Not summer.
Also it really has nothing to do with the condensation issues. Even at 180*F you still dont remove water from the fluid. Water changes state at 212*F.
One can only guess what the fluid temp is at the clutch, drums, bearings ect.
In general if you have your temp sender in the pressure port the TFT average is 20*F hotter than what you see on the gauge.
99% of the time if you remove a stat from a motor it will run hotter/overheat.
Just takes longer for it to happen.(summer)
You want to run a diesel as hot as you can 200+. Not the trans.
Bill
Postmaster
Joined: Feb 2004
Posts: 3,266
Likes: 0
From: Levittown
Originally Posted by MikeFromShiloh
QUESTION - I have a 95. Does that mean the Napa stat will work fine? or is there somehting I have missed?
Bill
Elder User
Joined: Aug 2006
Posts: 674
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From: KC, MO
As the temp. goes up the perf. goes down, correct? We want to keep the temp. down at some spots but up in some others.
For someone who doesn't want to trade out stats every six months, would you all prefer to leave in the orig. or not.
I have a 203 and I run veggie. I don't pull a lot and I am running the black tru-cool tranny cooler. I don't have the 203 installed yet. Would you all install it?
What are the downfalls?
I don't have a intercooler, what problems will I have?
thanks,
Fletch
For someone who doesn't want to trade out stats every six months, would you all prefer to leave in the orig. or not.
I have a 203 and I run veggie. I don't pull a lot and I am running the black tru-cool tranny cooler. I don't have the 203 installed yet. Would you all install it?
What are the downfalls?
I don't have a intercooler, what problems will I have?
thanks,
Fletch
Post Fiend
Joined: Apr 2004
Posts: 12,835
Likes: 3
From: Silver Lake Dunes, MI
You won't have any problems with it installed. For trans you want cooler temps but for the engine you want hotter temps for the coolant.
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Joined: Sep 2006
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From: Ridgeville,S.C.
Madvan,
Can you tell exactly how you are set up as far as bypassing the trans cooler in the summer. It sounds like you have two valves installed where the hoses go into the radiator with a small hose to create a loop. I received notice my 203 stat is at the post office, yesterday. I want to install it because it seems to help a lot with smooth engine acceleration. BUT, I pull a 38' horse trailer and don't want to possibly do damage unknowingly to the transmission. I have 5 speed manual, no gauges to monitor temperatures, except factory ones. Also when you bypass the cooler in the radiator, do you have another trans cooler somewhere else? I'm sure this is probably at a very basic level for some of you. I just want make sure I fully understand what I'm fixing to do and it's side effects. I want to install the 203 stat but don't want to harm anything else. Thanks for the time ,CJ
Can you tell exactly how you are set up as far as bypassing the trans cooler in the summer. It sounds like you have two valves installed where the hoses go into the radiator with a small hose to create a loop. I received notice my 203 stat is at the post office, yesterday. I want to install it because it seems to help a lot with smooth engine acceleration. BUT, I pull a 38' horse trailer and don't want to possibly do damage unknowingly to the transmission. I have 5 speed manual, no gauges to monitor temperatures, except factory ones. Also when you bypass the cooler in the radiator, do you have another trans cooler somewhere else? I'm sure this is probably at a very basic level for some of you. I just want make sure I fully understand what I'm fixing to do and it's side effects. I want to install the 203 stat but don't want to harm anything else. Thanks for the time ,CJ
Posting Guru
Joined: Nov 2006
Posts: 1,059
Likes: 0
From: Herndon KY
Originally Posted by 1997stroker
Madvan,
Can you tell exactly how you are set up as far as bypassing the trans cooler in the summer. It sounds like you have two valves installed where the hoses go into the radiator with a small hose to create a loop. I received notice my 203 stat is at the post office, yesterday. I want to install it because it seems to help a lot with smooth engine acceleration. BUT, I pull a 38' horse trailer and don't want to possibly do damage unknowingly to the transmission. I have 5 speed manual, no gauges to monitor temperatures, except factory ones. Also when you bypass the cooler in the radiator, do you have another trans cooler somewhere else? I'm sure this is probably at a very basic level for some of you. I just want make sure I fully understand what I'm fixing to do and it's side effects. I want to install the 203 stat but don't want to harm anything else. Thanks for the time ,CJ
Can you tell exactly how you are set up as far as bypassing the trans cooler in the summer. It sounds like you have two valves installed where the hoses go into the radiator with a small hose to create a loop. I received notice my 203 stat is at the post office, yesterday. I want to install it because it seems to help a lot with smooth engine acceleration. BUT, I pull a 38' horse trailer and don't want to possibly do damage unknowingly to the transmission. I have 5 speed manual, no gauges to monitor temperatures, except factory ones. Also when you bypass the cooler in the radiator, do you have another trans cooler somewhere else? I'm sure this is probably at a very basic level for some of you. I just want make sure I fully understand what I'm fixing to do and it's side effects. I want to install the 203 stat but don't want to harm anything else. Thanks for the time ,CJ
Postmaster
Joined: Feb 2004
Posts: 3,266
Likes: 0
From: Levittown
Seems i started a slight pannic over this.
The 203 stat is not going to hurt your trans. It will/can make it run hotter in the summer time. It does not need the heat. Fords overheat to set a code is 270*f at the TFT. On your gauge thats about 250*F "overheat". My statement is for trans and fluid life. The cooler it is the longer it will last.
As a test come summer just bend up a small piece of 5/16 or 3/8 (you could have either) hard line to mimic the liquid cooler. Pull the lines off the rad and install your hard line with the clamps.
Testing has been all over the map. Some have no change in the temp, some run cooler an in SD its been found that they will run hotter when removed. The bottom of the rad is the coolest part of the cooling system.
No 2 trucks are the same after mods to the truck (motor,trans,tires,ect). And how you use the truck.
I have found 15 to 20*f cooler fluid with it removed. ("summer").
I like to see 160/180 average temps with syn fluid for a long trans and fluid life.
Bill
The 203 stat is not going to hurt your trans. It will/can make it run hotter in the summer time. It does not need the heat. Fords overheat to set a code is 270*f at the TFT. On your gauge thats about 250*F "overheat". My statement is for trans and fluid life. The cooler it is the longer it will last.
As a test come summer just bend up a small piece of 5/16 or 3/8 (you could have either) hard line to mimic the liquid cooler. Pull the lines off the rad and install your hard line with the clamps.
Testing has been all over the map. Some have no change in the temp, some run cooler an in SD its been found that they will run hotter when removed. The bottom of the rad is the coolest part of the cooling system.
No 2 trucks are the same after mods to the truck (motor,trans,tires,ect). And how you use the truck.
I have found 15 to 20*f cooler fluid with it removed. ("summer").
I like to see 160/180 average temps with syn fluid for a long trans and fluid life.
Bill