8 speed Trans cooler bypass upgrade. Anyone familiar with this? Rev tec....

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lAWROSA

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kurek

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It's only called an upgrade if the result is an improvement.

Thermostats and heat exchangers extend the life of equipment and reduce wear, and delay the onset of leaks by reducing the number of thermal cycles an assembly experiences.
 

joesstripclub

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Start Here There is a link in the first post where the discussion starts off talking about the RevMax kit then diverts later into Caulk04 making his own part that basically does the same thing for a fraction of the price. I think I am one of the few who bought and installed the revmax kit, but I am very happy with it. I havent seen transmission temps above 160 (light towing in the mountains of colorado) so it definitely works.
 

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It's only called an upgrade if the result is an improvement.

Thermostats and heat exchangers extend the life of equipment and reduce wear, and delay the onset of leaks by reducing the number of thermal cycles an assembly experiences.
Normally you would be right, but this is a heat exchanger to heat up the transmission not cool it down.
 

kurek

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Man it's too bad all the engineers at Ram and ZF can build the actual best automatic transmission in the world but then don't know how to regulate its temperature correctly it sure is a good thing that random people on forums exist to solve their complex engineering problems for them.
 

HEMIMANN

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Transmission oil temp heating is as absurd as MDS for fuel savings, introduces significant cost and complexity, and more failure points.

Add inadequate design and it's a kluge. Look at the oil flow area around the trans thermostat and compare to the pipe. It's a restrictive orifice even when it hasn't failed.
And yes I am a degreed engineer with 33 years experience of successful powertrain designs in production and service worldwide. Doesn't mean I'm expert at everything but I do have street cred and this is a simple analysis.
 

Wild one

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Man it's too bad all the engineers at Ram and ZF can build the actual best automatic transmission in the world but then don't know how to regulate its temperature correctly it sure is a good thing that random people on forums exist to solve their complex engineering problems for them.
The same transmission in the cars doesn't use a coolent heater to heat the fluid like they do in the trucks.Here's a very c rappy pic of the 8HP70's temp after 40+ miles in my wifes 2019 6.4 Challenger.The HD trucks also don't heat the fluid in their 8 speeds,and hardly get over 160F unloaded and maybe 170 towing.Just food for thought for you to chew on.
 

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Wild one

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2014-2020 Dodge Ram 8HP70, 8HP75 Transmission Cooler Thermostat Bypass​


https://revmaxconverters.com/produc...-8hp75-transmission-cooler-thermostat-bypass/

This is on the books for one of my upgrades. Although these trucks have something different then the other typical 4 port bypass units out there.

although I have not got under the truck to look.
There's 3 options with that kit,the only one that works and won't cook your 8 speed is option #3,the first 2 options will restrict flow,and cook your 8sp.
 

kurek

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Add inadequate design and it's a kluge. Look at the oil flow area around the trans thermostat and compare to the pipe. It's a restrictive orifice even when it hasn't failed.
And yes I am a degreed engineer

So wouldn't the correct solution be to take the design their engineers produced and un-count some beans to increase flow or increase peak cooling capacity?

Putting these parts in there wasn't a cost saving measure, maybe they made the parts as cheap as they possibly could but the cheapest part is no part and they clearly decided it needed a part. They wouldn't have spent the money putting these things on the truck as a joke to make it wear out faster.

I see this stuff in forums all the time, like my wife has an old V6 Mustang and from the ~98 model year to the ~02 model year they added 50 horsepower to those cars by putting different heads on, extremely heavy and expensive cast aluminum dual runner intake manifolds with electrically operated valves on the short runners, and they use the same MAF and air filter as the much more powerful V8 version of the car. Then people get on forums and say they're gonna make tons of power with an aftermarket air filter.
Well shucks man I'm glad ebay seller SpeedyStuff1234 came along with that one size fits all cone air filter too bad Ford didn't have him on staff they could have saved a fortune on engineering and inventorying those new heads and manifolds and runner servos..


I'm not suggesting that modifying a vehicle is always pointless, we all modify ours to do what we need them to accomplish but that's not the same thing. When you raise the ride height for example you know you're trading a little fuel efficiency for a little ground clearance, you're shifting the priorities on trade-offs that are necessary. When you just remove a part the manufacturer spent money on engineering and installing, and you don't get anything from removing it except some imaginary and unproven guesses about distant future reliability.. I just don't get it and probably never will.
 

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Heat is the enemy of transmissions and clutch packs, keeping it under 200f is gonna make your transmission last longer, and the lower the better to a point. We all know the "engineers" didnt heat the 8 speed for performance, they did it for gov't api goals. This may shock some people, but the climate change people really don't care if your truck transmission outlasts the truck, that is your job. If you think you can do that running a hot transmission, good luck with that.

The beauty of the 8 speed is the gears that keep the engine in good rpm's and not low rpm's that are an insufficient way to burn gas. That is where most of the gas mileage comes from, not the pre heated fluid.
 

kurek

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It's just really weird how they could get so much right inside the transmission but then need to turn to internet forums for help with the stuff outside it but you have to admit it's super convenient that the things people on forums know better about always happen to be the things you can get at from outside and improve by just removing them.
 

HEMIMANN

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So wouldn't the correct solution be to take the design their engineers produced and un-count some beans to increase flow or increase peak cooling capacity?

Putting these parts in there wasn't a cost saving measure, maybe they made the parts as cheap as they possibly could but the cheapest part is no part and they clearly decided it needed a part. They wouldn't have spent the money putting these things on the truck as a joke to make it wear out faster.

I see this stuff in forums all the time, like my wife has an old V6 Mustang and from the ~98 model year to the ~02 model year they added 50 horsepower to those cars by putting different heads on, extremely heavy and expensive cast aluminum dual runner intake manifolds with electrically operated valves on the short runners, and they use the same MAF and air filter as the much more powerful V8 version of the car. Then people get on forums and say they're gonna make tons of power with an aftermarket air filter.
Well shucks man I'm glad ebay seller SpeedyStuff1234 came along with that one size fits all cone air filter too bad Ford didn't have him on staff they could have saved a fortune on engineering and inventorying those new heads and manifolds and runner servos..


I'm not suggesting that modifying a vehicle is always pointless, we all modify ours to do what we need them to accomplish but that's not the same thing. When you raise the ride height for example you know you're trading a little fuel efficiency for a little ground clearance, you're shifting the priorities on trade-offs that are necessary. When you just remove a part the manufacturer spent money on engineering and installing, and you don't get anything from removing it except some imaginary and unproven guesses about distant future reliability.. I just don't get it and probably never will.

We used to rank projects for new products and product improvements by cost / benefit ration using defined metrics. It wasn't all just money, either - there were regulatory (legal) burdens, critical customer quirks, etc. These hardly qualify. I don't need to run the numbers on these to prove it - after decades of doing this, it's fairly obvious here.
 
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lAWROSA

lAWROSA

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Start Here There is a link in the first post where the discussion starts off talking about the RevMax kit then diverts later into Caulk04 making his own part that basically does the same thing for a fraction of the price. I think I am one of the few who bought and installed the revmax kit, but I am very happy with it. I havent seen transmission temps above 160 (light towing in the mountains of colorado) so it definitely works.
excellent info you just gave me. Did you do the block off plate and all?

Yes this is what I experienced with my old chevy with the two trans coolers. Id tow all day. 160-170 max..

I know its heat that kills a trans. Lower temps longer lasting.
 
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lAWROSA

lAWROSA

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So wouldn't the correct solution be to take the design their engineers produced and un-count some beans to increase flow or increase peak cooling capacity?

Putting these parts in there wasn't a cost saving measure, maybe they made the parts as cheap as they possibly could but the cheapest part is no part and they clearly decided it needed a part. They wouldn't have spent the money putting these things on the truck as a joke to make it wear out faster.

I see this stuff in forums all the time, like my wife has an old V6 Mustang and from the ~98 model year to the ~02 model year they added 50 horsepower to those cars by putting different heads on, extremely heavy and expensive cast aluminum dual runner intake manifolds with electrically operated valves on the short runners, and they use the same MAF and air filter as the much more powerful V8 version of the car. Then people get on forums and say they're gonna make tons of power with an aftermarket air filter.
Well shucks man I'm glad ebay seller SpeedyStuff1234 came along with that one size fits all cone air filter too bad Ford didn't have him on staff they could have saved a fortune on engineering and inventorying those new heads and manifolds and runner servos..


I'm not suggesting that modifying a vehicle is always pointless, we all modify ours to do what we need them to accomplish but that's not the same thing. When you raise the ride height for example you know you're trading a little fuel efficiency for a little ground clearance, you're shifting the priorities on trade-offs that are necessary. When you just remove a part the manufacturer spent money on engineering and installing, and you don't get anything from removing it except some imaginary and unproven guesses about distant future reliability.. I just don't get it and probably never will.
heat kills a trans. You want trans cool as possible. To heat it to 200 plus degrees is absurd.

https://lh3.googleusercontent.com/p...2GrW51RjeQ4gwzuJYgDcuBlGHN1fXdJvusj1sbyJgdydj
 

Wild one

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excellent info you just gave me. Did you do the block off plate and all?

Yes this is what I experienced with my old chevy with the two trans coolers. Id tow all day. 160-170 max..

I know its heat that kills a trans. Lower temps longer lasting.
Don't do the over priced Revmax kit,get ahold of Jesse Caulk/Caulk04 on here,and get one of his bypass valves instead.It's cheaper and easier to install,plus it's also easier to reverse if you decide you don't like it.If you read the second link,you'll see how CrazyKid and i did ours,but we did ours before Jesse had his bypass valve in production.In hindsight ,if i was doing it again,i'd buy Jesse's valve.The only thing you realistically use from the Rev Max kit is the plate,i started with that kit,and abandoned it in short order,and totally deleted the heat exchanger and all it's plumbing.Start reading about page 24 or 25 to see how CrazyKid and i deleted the bulky heat exchanger.

 

MRFREEZE57

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Don't do the over priced Revmax kit,get ahold of Jesse Caulk/Caulk04 on here,and get one of his bypass valves instead.It's cheaper and easier to install,plus it's also easier to reverse if you decide you don't like it.If you read the second link,you'll see how CrazyKid and i did ours,but we did ours before Jesse had his bypass valve in production.In hindsight ,if i was doing it again,i'd buy Jesse's valve.The only thing you realistically use from the Rev Max kit is the plate,i started with that kit,and abandoned it in short order,and totally deleted the heat exchanger and all it's plumbing.Start reading about page 24 or 25 to see how CrazyKid and i deleted the bulky heat exchanger.


I have one of Caulk4's t stat bypass in my truck, about 90 min of my time to install. before on warmer days in traffic would see 188 deg, that is with a PPE pan, now the most have seen in stop and go is 160 deg, when moving around 135-140 a huge improvement over the t stat that was in before. A well worthwhile investment and looks much simpler to install than the Revmax kit.
 

joesstripclub

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excellent info you just gave me. Did you do the block off plate and all?

Yes this is what I experienced with my old chevy with the two trans coolers. Id tow all day. 160-170 max..

I know its heat that kills a trans. Lower temps longer lasting.
Yes you need to install both parts if you go with this kit. Like WildOne said, installing only 1 of the pieces was determined to be bad news for your trans. Caulk04s part does the same thing with only 1 piece instead of two since he went about it differently. If for some reason you just want to support RevMax, make sure you put RTV on both sides of the plate to make sure you dont get any leaks.
 
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