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4th Gen Powertrain Discussion of components that are directly involved in the power production and all that is needed to get and keep the truck moving . Engine, Transmission, etc...NO ADVERTISING

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  Topic Review (Newest First)
06-23-2019 02:31 PM
BFD Yep, fluid cooling is forgiving. If the flow is faster there is less heat exchange but the fluid passes through more often. The net affect isn't as drastic as the flow changes. No exchanger is 100%... You will never have 0* approach. Keeping exchangers clean is also critical. Approach temp goes up when the surfaces are dirty. That might be why some guys get more benefit from the tstat bypass... The air cooler is more plugged with bugs and dirt than the next guys cooler.
An extra bonus from cooler temp is firmer shifting. A Protect 68 or VB WAS going to be my next mod but I wouldn't want it shifting any harder than it does now. It's on the borderline of slamming, when in tow/haul. I think it's just right but that wasn't planned... I'd rather be "lucky" than "good", any day! Craig
06-19-2019 03:04 AM
HeavyTwo Automanfactures try their best to save even a fraction of a penny.

Knowing this, why would RAM install this? When just using straight lines, it would be much cheaper.

As BFD brought up, its to help the oil reach a set operating temperature. However, we all know that the cooler an Automatic the better. So, why would RAM want it at a set temperature?

Hotter oil flows better and "sucks" less power than cold oil. Also, you want the transmission to get hot enough to evaporate any water in the oil. Finally you have thermal heat transfer. The hot oil needs to remain in the cooler long enough for the air to extract the heat. Move the fluid too fast, and not all the heat will be removed. You may not notice this when operating under the limits of the cooler or not making heat in the transmission. However, under extreme conditions, the thermostat based system may cool better.

Finally, the transmission shifts differently based on temperature. When cold, it holds the lower gears longer. If you live in a cold climate it will take much longer for trans to reach this set temperature, affecting your MPG.

As I live just north of actual HELL, I'll delete my transmission thermostat.

I'm a firm believer that a cool transmision is a happy transmission.
06-18-2019 09:23 PM
RamHunter18 I installed the revmax one on my 18 and my unloaded temps went from 165 average to 120 average. It took all of 10 min to install. Lost virtually no fluid
06-18-2019 07:52 PM
BFD Sorry for the duplicate post but my phone was not showing me my earlier post.
06-18-2019 07:50 PM
BFD Do a search and read about how transmissions life goes down as temperature goes up. That thermostat block wasn’t put there to make the transmission last longer. Craig
06-18-2019 02:36 PM
BFD That thermostat is there to get the transmission and fluid hotter so there is less drag from thick fluid. I took the thermostat cartridge out of mine and made a plug to drive into the center of the block so that flow is always to the cooler and my trans ran 20 Cooler. I’ll take a cooler transmission over hotter any day. I’ve known a lot of transmission builders who told me they never heard of overcooling an automatic. Do a search on automatic transmissions and heat and you’ll see how as heat goes up life of the transmission goes down. My truck came with the max tow welded plate exchanger which is basically another fluid heater because it supposedly cools the fluid with engine water. I did away with that exchanger and replaced it with a fan powered remote Derale cooler and now my transmission runs 150 towing. Craig
06-18-2019 02:09 PM
cwendel Would have been a normal 1 beer job except for the way the lines fit.

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06-18-2019 02:08 PM
cwendel The rev max was a pain to install because the end where the threaded lines from the trans attach are not quite right. They are offset where the original has them even with each other. The ats looks to more parallel the stock unit. Because of the lines, it took forever with me under the truck and a broken jack. The fittings need stubby wrenches to loosen and tighten because of the space. And i lost about 3 qts of fluid during the process. Should have put the truck on ramps but you live and learn.

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06-18-2019 01:30 PM
Originally Posted by Micheal28188 View Post
What im unsure about is wether it's worth it or if it even matters
Originally Posted by Micheal28188 View Post
Well I'll be deleting it after the warranty is up
Glad to see you're listening to the people replying to your thread. Welcome to the forum...
06-18-2019 01:14 PM
Originally Posted by cwendel View Post
Bought the rev max one. Get the ats one, i think it is made better but the temps on my trans have dropped 10-20 degrees. Much cooler while towing my TT at 70.

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How was the install? Any tips? Any unexpected pain in the butts? How long did it take?

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06-18-2019 12:14 PM
cwendel Bought the rev max one. Get the ats one, i think it is made better but the temps on my trans have dropped 10-20 degrees. Much cooler while towing my TT at 70.

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06-17-2019 10:52 PM
Micheal28188 Well I'll be deleting it after the warranty is up and I know some power is added with a delete tune even though I'm not looking for more power. I'm deleting for mpg and not having to deal with this stupid egr and def its gave nothing but problems and only has 50k.
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