Pros and cons of running stock and aftermarket cooler?
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Alright I have the B&M 70264 cooler waiting to go in along with my stall. I'd like to run it inline with the stock cooler. What are the pros and cons of this and how would I go about
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There is a lot of debate on this topic - if you search you'll probably find it.
I am not what B&M recommends, but the papers that came with my Perma-Cool cooler said that I should run it through the stock radiator trans cooler first.
Most guys with stalls will tell you that they have bypassed it.
I bypassed mine, but I do not have a 4L60E - I have a 4L80E. I used a fluid thermostat, which bypasses my aftermarket cooler completely until the transmission temp is up to operating temp (160-180*). I did this because I wanted to stay away from unnecessary restriction in the cooler lines, and the diameter of the radiator cooler is pretty small. My 4L80E also came out of cargo van, which did not have a radiator cooler, but a small external cooler.
I am sure more people will chime in with their thoughts.
I am not what B&M recommends, but the papers that came with my Perma-Cool cooler said that I should run it through the stock radiator trans cooler first.
Most guys with stalls will tell you that they have bypassed it.
I bypassed mine, but I do not have a 4L60E - I have a 4L80E. I used a fluid thermostat, which bypasses my aftermarket cooler completely until the transmission temp is up to operating temp (160-180*). I did this because I wanted to stay away from unnecessary restriction in the cooler lines, and the diameter of the radiator cooler is pretty small. My 4L80E also came out of cargo van, which did not have a radiator cooler, but a small external cooler.
I am sure more people will chime in with their thoughts.
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Cool man thanks for the insight. I tried searching on my phone but this mobile site ain't doing the job lol. Id like to run both but if its a pain or the cons outweigh the pros, then I obviously won't be doing it.
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Here's a write up i did on tranny coolers a while back. I ran my B&M in addition to the factory cooler, which is what most every manufacterer will reccomend. Run it "after" the factory cooler in the return line because the aftermarket cooler is obviously more effective than the stock one, thus if the aftermarket cooler is the last place the fluid is before it returns to the tranny, it will be the coolest when it returns. Real easy install, here's the write up:
https://ls1tech.com/forums/automatic...0e-f-body.html
Theres also an animated diagram of how it works in there.
https://ls1tech.com/forums/automatic...0e-f-body.html
Theres also an animated diagram of how it works in there.
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Here's a write up i did on tranny coolers a while back. I ran my B&M in addition to the factory cooler, which is what most every manufacterer will reccomend. Run it "after" the factory cooler in the return line because the aftermarket cooler is obviously more effective than the stock one, thus if the aftermarket cooler is the last place the fluid is before it returns to the tranny, it will be the coolest when it returns. Real easy install, here's the write up:
https://ls1tech.com/forums/automatic...0e-f-body.html
Theres also an animated diagram of how it works in there.
https://ls1tech.com/forums/automatic...0e-f-body.html
Theres also an animated diagram of how it works in there.
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Right now I run my 1 aftermarket cooler (b&m70264) by itself. Up until snowfall this year I was drivng the car. Temps outside were below freezing. When I would start the car up from it sitting over night or a couple days, reading trans temps off the pcm would say average 20-30f. Im not a believer in the idea of trans fluid jelling up. I let it sit until closed loop and waited till trans temp was above freezing before driving the car. No problems.
Last summer I actualy ran a 2 cooler setup (both b&m70264) and believe it or not trans temps were not very much different. So maybe the extra pressure caused by the extra cooler lines cause enough heat to make temps the same as just 1 cooler? Who knows.
The main idea of bypassing the stock cooler is to keep the trans fluid away from the hotter coolant which goes through the radiator. In the beggining I was one to believe that using stock cooler in series w/aftermarket would be best option. But I choose to listen to the guys that have suposedly tried it and said its better to bypass. I personaly dont know for sure if bypassing stock cooler actualy aids in keeping trans fluid cooler. I havent done testing on it that way. But I may try it out next summer. I like to do my own research instead of just hearing opinions with no proof.
Iv tried mounting coolers in a few different locations. I found that mounted on the radiator works best. But I have a CAI kit so I have mine in a sort of non traditional dope style way.
When I get a stall this year ill most likely be trying more ways. Work is never ******* done LOL
Last summer I actualy ran a 2 cooler setup (both b&m70264) and believe it or not trans temps were not very much different. So maybe the extra pressure caused by the extra cooler lines cause enough heat to make temps the same as just 1 cooler? Who knows.
The main idea of bypassing the stock cooler is to keep the trans fluid away from the hotter coolant which goes through the radiator. In the beggining I was one to believe that using stock cooler in series w/aftermarket would be best option. But I choose to listen to the guys that have suposedly tried it and said its better to bypass. I personaly dont know for sure if bypassing stock cooler actualy aids in keeping trans fluid cooler. I havent done testing on it that way. But I may try it out next summer. I like to do my own research instead of just hearing opinions with no proof.
Iv tried mounting coolers in a few different locations. I found that mounted on the radiator works best. But I have a CAI kit so I have mine in a sort of non traditional dope style way.
When I get a stall this year ill most likely be trying more ways. Work is never ******* done LOL
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I know from personal experience that it is hard for coolant to get into the transmission lines if the internal cooler broke. It is always reverse. the radiator fills with transmission fluid. Its simple math, radiator 14-18 psi. trans line 180-200+ psi. now even though it would be nice to completely get away from this problem ever occurring I have always wondered the benefit of allowing the coolant to heat the trans fluid when warming up. I would think that an after market cooler inline with the stock cooler is the best option. Of course after the stock cooler as well.
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I assure you that the pressure running through your cooler lines is not 180 psi. That might be your "line pressure" inside the transmission, but it is not the pressure of the fluid going through the cooler system. If it was, my crappy temporary cooler line setup would have blown apart a long time ago. I don't know the exact pressure, but I think it's around 40 psi, but I'm not sure... I've seen varying numbers. This is still higher than the cooling system, so you would be pushing trans oil into the coolant. That is a very good point!
I know from personal experience that it is hard for coolant to get into the transmission lines if the internal cooler broke. It is always reverse. the radiator fills with transmission fluid. Its simple math, radiator 14-18 psi. trans line 180-200+ psi. now even though it would be nice to completely get away from this problem ever occurring I have always wondered the benefit of allowing the coolant to heat the trans fluid when warming up. I would think that an after market cooler inline with the stock cooler is the best option. Of course after the stock cooler as well.
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You are correct that the cooler line pressure is not that high. I guess the way I wrote it did appear to be that way. I meant just trans line pressure is general not actually at the cooler. I've never actually measured it a cooler. If I had to guess I would estimate between 30-60 psi actually within the cooler itself.
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Right now I run my 1 aftermarket cooler (b&m70264) by itself. Up until snowfall this year I was drivng the car. Temps outside were below freezing. When I would start the car up from it sitting over night or a couple days, reading trans temps off the pcm would say average 20-30f. Im not a believer in the idea of trans fluid jelling up. I let it sit until closed loop and waited till trans temp was above freezing before driving the car. No problems.
The main idea of bypassing the stock cooler is to keep the trans fluid away from the hotter coolant which goes through the radiator. In the beggining I was one to believe that using stock cooler in series w/aftermarket would be best option. But I choose to listen to the guys that have suposedly tried it and said its better to bypass. I personaly dont know for sure if bypassing stock cooler actualy aids in keeping trans fluid cooler. I havent done testing on it that way. But I may try it out next summer. I like to do my own research instead of just hearing opinions with no proof.
The main idea of bypassing the stock cooler is to keep the trans fluid away from the hotter coolant which goes through the radiator. In the beggining I was one to believe that using stock cooler in series w/aftermarket would be best option. But I choose to listen to the guys that have suposedly tried it and said its better to bypass. I personaly dont know for sure if bypassing stock cooler actualy aids in keeping trans fluid cooler. I havent done testing on it that way. But I may try it out next summer. I like to do my own research instead of just hearing opinions with no proof.
What you aim to accomplish should influence your choice of going through the stock cooler.
My goal is to keep the trans fluid between 160-180*. I want my trans fluid up to operating temperature ASAP. As a result, running through the radiator would make sense in most circumstances. Most would argue this is what the stock trans cooler was put there for in the first place... to warm up the trans fluid when it's cold, and cool it off when it's too hot. (See my post above - I actually used a separate thermostat for my trans fluid that bypasses the cooler until it warms up. I think that's the best solution to accomplish a consistent and cool trans fluid temp.)
However, if your aim is to keep the fluid as cool as possible for as long as possible, running through a separate aftermarket cooler only is an attractive option. It's also very simple, which is a good thing!! However, as long as the coolant in that side tank (the radiator's cooler outlet side) is cooler than the trans fluid, you will be taking heat out of the trans fluid and putting it in your engine coolant. If your target trans temp is really low, then you could get to a point where the radiator trans cooler would almost always add heat.
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I ran Yank ST3500 5 years with no temp guage with OE cooler and 24000 fin and plate cooler/fan installed after OE cooler, and bunt 2 sets of 3/4 clutches, about 8-900 miles ago installed Yank SS4000 AND 24000 tube type with fan and ADDED temp guage in pan still going threw OE cooler allso, after TC lock up @ 45 mph running temp about 180-190, but if cruies in town @ 10-15 mph temp goes to 220-230 , tried bypass OE cooler and temp DID NOT change still slow cruise at 220-230 I am going to reconnect the OE and stay out of slow town cruise.
both of the ext coolers are mounted DOPE STYLE
ps : I talked to the trans tech at local dealership how goes to dealer school each 6 months for update on trans, he stated that shool teaches that IF bypass OE cooler the external cooler looses about 40% of its cooling effinishse
I was also told that to run more that one ext cooler they MIGHT cause high trans pressure which would cause high trans temp ?
as stated I am running OE cooler/ one 24000 plate and fin with fan/ one 24000 tube type and fan and still IF do town cruise @ 10-15 mph beyound 10-15 minutes still running 220-230 trans temp ??
I also need help
MY apoligy to the OP, sorry for stepping on ypur post
Johnny
both of the ext coolers are mounted DOPE STYLE
ps : I talked to the trans tech at local dealership how goes to dealer school each 6 months for update on trans, he stated that shool teaches that IF bypass OE cooler the external cooler looses about 40% of its cooling effinishse
I was also told that to run more that one ext cooler they MIGHT cause high trans pressure which would cause high trans temp ?
as stated I am running OE cooler/ one 24000 plate and fin with fan/ one 24000 tube type and fan and still IF do town cruise @ 10-15 mph beyound 10-15 minutes still running 220-230 trans temp ??
I also need help
MY apoligy to the OP, sorry for stepping on ypur post
Johnny
Last edited by SS SLP2; 01-26-2011 at 08:24 PM.
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Coolant does enter into the trans. When driving yes the oil pressure forces oil into the radiator, but when you shut the car off the oil pressure goes bye bye but the radiator stays pressurized until cooled down.
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I ran Yank ST3500 5 years with no temp guage with OE cooler and 24000 fin and plate cooler/fan installed after OE cooler, and bunt 2 sets of 3/4 clutches, about 8-900 miles ago installed Yank SS4000 AND 24000 tube type with fan and ADDED temp guage in pan still going threw OE cooler allso, after TC lock up @ 45 mph running temp about 180-190, but if cruies in town @ 10-15 mph temp goes to 220-230 , tried bypass OE cooler and temp DID NOT change still slow cruise at 220-230 I am going to reconnect the OE and stay out of slow town cruise.
both of the ext coolers are mounted DOPE STYLE
ps : I talked to the trans tech at local dealership how goes to dealer school each 6 months for update on trans, he stated that shool teaches that IF bypass OE cooler the external cooler looses about 40% of its cooling effinishse
I was also told that to run more that one ext cooler they MIGHT cause high trans pressure which would cause high trans temp ?
as stated I am running OE cooler/ one 24000 plate and fin with fan/ one 24000 tube type and fan and still IF do town cruise @ 10-15 mph beyound 10-15 minutes still running 220-230 trans temp ??
I also need help
MY apoligy to the OP, sorry for stepping on ypur post
Johnny
both of the ext coolers are mounted DOPE STYLE
ps : I talked to the trans tech at local dealership how goes to dealer school each 6 months for update on trans, he stated that shool teaches that IF bypass OE cooler the external cooler looses about 40% of its cooling effinishse
I was also told that to run more that one ext cooler they MIGHT cause high trans pressure which would cause high trans temp ?
as stated I am running OE cooler/ one 24000 plate and fin with fan/ one 24000 tube type and fan and still IF do town cruise @ 10-15 mph beyound 10-15 minutes still running 220-230 trans temp ??
I also need help
MY apoligy to the OP, sorry for stepping on ypur post
Johnny
So my Philosophy about the 2 coolers on my car cooling the same as one has someone else saying the same thing. Interesting
#18
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What you aim to accomplish should influence your choice of going through the stock cooler.
My goal is to keep the trans fluid between 160-180*. I want my trans fluid up to operating temperature ASAP. As a result, running through the radiator would make sense in most circumstances. Most would argue this is what the stock trans cooler was put there for in the first place... to warm up the trans fluid when it's cold, and cool it off when it's too hot. (See my post above - I actually used a separate thermostat for my trans fluid that bypasses the cooler until it warms up. I think that's the best solution to accomplish a consistent and cool trans fluid temp.)
However, if your aim is to keep the fluid as cool as possible for as long as possible, running through a separate aftermarket cooler only is an attractive option. It's also very simple, which is a good thing!! However, as long as the coolant in that side tank (the radiator's cooler outlet side) is cooler than the trans fluid, you will be taking heat out of the trans fluid and putting it in your engine coolant. If your target trans temp is really low, then you could get to a point where the radiator trans cooler would almost always add heat.
My goal is to keep the trans fluid between 160-180*. I want my trans fluid up to operating temperature ASAP. As a result, running through the radiator would make sense in most circumstances. Most would argue this is what the stock trans cooler was put there for in the first place... to warm up the trans fluid when it's cold, and cool it off when it's too hot. (See my post above - I actually used a separate thermostat for my trans fluid that bypasses the cooler until it warms up. I think that's the best solution to accomplish a consistent and cool trans fluid temp.)
However, if your aim is to keep the fluid as cool as possible for as long as possible, running through a separate aftermarket cooler only is an attractive option. It's also very simple, which is a good thing!! However, as long as the coolant in that side tank (the radiator's cooler outlet side) is cooler than the trans fluid, you will be taking heat out of the trans fluid and putting it in your engine coolant. If your target trans temp is really low, then you could get to a point where the radiator trans cooler would almost always add heat.
I did testing on 2 ext coolers, 1 ext cooler, coolers in 3 different locations, but didnt do a test with the stocker. Im guessing it might be more harm than good because of the added pressure created by the cooler lines/extra cooler.
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Also, to speak to the original post, there is also a theory that too much restriction in the trans cooling system (lines, cooler, fittings, etc) will damage the engine and/or transmission. Just a theory I've heard floating around. I have no experience with it, but it might be worth a search.