8HP70 Transmission Cooler

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SyN

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My 1500 at this time does not have an external heavy duty transmission cooler. During the summer months we toe a 6200 pound travel trailer.
During our summer months the ambient temperatures averages between 102-110° while towing. Thus the reason for me ordering & adding a external trans cooler. I want this trans to last way beyond the warranty period.

There are times after about an hour of towing that my transmission temperatures rise to scary not normal temperatures. I have seen temps right at 195-218*F---->That is not safe for any fluid semi or 100% full synthetic.

Even though some say the ZF transmission was designed to run at these temps many are for getting the most valuable part (the fluid) is not designed to run at these temps for long periods of time. The ZF fluid is semi-synthetic. This is all just my opinion and nothing will really change that opinion.

Anyway on the discussion of a external transmission cooler it seems I remember there is a proper way to install one in a not proper way to install one.

If I remember correctly the proper way is to mount the cooler (mount the cooler on its side) where the lines coming in are at the side the inlet line is at the bottom the return line is at the top that way the cooler gets completely filled with fluid for maximum cooling.
If you mount the cooler with the lines coming in and returning at the bottom you take a chance of the transmission cooler not being completely filled with fluid thus not being very efficient.

If my assumption on the installation is wrong please someone correct me.
 
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AFMoulton

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My 1500 at this time does not have an external heavy duty transmission cooler. During the summer months we toe a 6200 pound travel trailer.
During our summer months the ambient temperatures averages between 102-110° while towing. Thus the reason for me ordering & adding a external trans cooler. I want this trans to last way beyond the warranty period.

There are times after about an hour of towing that my transmission temperatures rise to scary not normal temperatures. I have seen temps right at 195-218*F---->That is not safe for any fluid semi or 100% full synthetic.

Even though some say the ZF transmission was designed to run at these temps many are for getting the most valuable part (the fluid) is not designed to run at these temps for long periods of time. The ZF fluid is semi-synthetic. This is all just my opinion and nothing will really change that opinion.

Anyway on the discussion of a external transmission cooler it seems I remember there is a proper way to install one in a not proper way to install one.

If I remember correctly the proper way is to mount the cooler (mount the cooler on its side) where the lines coming in are at the side the inlet line is at the bottom the return line is at the top that way the cooler gets completely filled with fluid for maximum cooling.
If you mount the cooler with the lines coming in and returning at the bottom you take a chance of the transmission cooler not being completely filled with fluid thus not being very efficient.

If my assumption on the installation is wrong please someone correct me.



SyN, what I was saying yesterday was to use an aftermarket one with a fan attached to replace factory cooler. Also, in my research on this you are correct in the way to install it. At least that's the way I'm doing mine.

The active grille shutters cause our problem also I think. The trans cooler is the top 1/3 of the ac condenser piece. The shutters close off all but the bottom 1/4 of the grille opening. I have no clue why, but I figure if I remove those, mount my own trans cooler, to take the place of the "factory" one, have a switched electric fan on it, I can manage the temps with the flip of a switch.

Not sure if that's kind of the same track you are on, but towing my TT, 7400 lbs loaded, my trans has hit 215 once and that was once to many IMHO.


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SyN

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These dad gum active grill shutters are not Standard equipment are they?

My trans lines do not tie into the a/c condenser, they are plumbed into the bottom of the radiator. Which makes sense since I do not have an stock heavy duty transmission cooler from the factory. Which is plumbed into to the AC condenser like you said.

All I am looking for is a 20 to 30° temperature drop in my transmission temperature this aftermarket transmission cooler that I ordered is said to do that. No more money has to be spent or nothing else needs to be done.

I do have a gut feeling though that both in-line transmission coolers will be fighting this heat exchanger all the time. Since it wants the trans fluid a certain temp. I am curious though if this is only active during start up and not at normal operation temp? Or if the transmission fluid temperature drops below a certain temp if it will kick on to heat it back up?

Rod has the (Factory)HD auxiliary trans cooler and he says he never sees over 174*F with his 8HP70. I would be thrilled with those results.

Thanks for you input.
 
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BossHogg

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Rod has the (Factory)HD auxiliary trans cooler and he says he never sees over 174*F with his 8HP70. I would be thrilled with those results.

Thanks for you input.

You are fixing something that is not broken, despite what you believe about the transmission fluid operating properties, do the research. Operating temperature of 174 degrees is likely to shorten the operational life of the transmission.
 

SyN

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These just totally contradicts what you spewed out! Oh I am full of research!!
 

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SyN

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2 more of My Research! Also I know the chatter is that these transmissions are designed to run at 192°. The fluid is not! Made some time to contact ZF again Todd--->the ZF tech that I talked to told me adding an additional transmission cooler would only benefit my transmission in the long run. That's all I needed to hear!

I am only installing what RAM installed at the factory. Good thing is mine will be a little bit more efficient.

If what you say is true? LoL! Why would ram install a factory heavy duty transmission cooler to cool the fluid down to shorten the life of the transmission? They would be replacing a lot of transmissions under warranty.
 

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SyN

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You are fixing something that is not broken, despite what you believe about the transmission fluid operating properties, do the research. Operating temperature of 174 degrees is likely to shorten the operational life of the transmission.

I do appreciate your input. I can honestly say this is the first time in 37 years that I've ever heard this.

You must've really put a ton of time and effort into your research to find this info.

Thanks again!
 

SyN

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More of my research over the years.
 

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AFMoulton

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LoL SyN, your posts are the best. I'm actively trying to lower my temps on my 8HP70' I heard or read, that there is a way to change the thermostat for the heat exchanger on the tranny. I'll see if I can find it.


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SyN

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Here is a simple diagram of how my cooler will be placed in the flow. My Magnefine will still be in place in-line between the cooler in the radiator & the new auxiliary Derale 9000 cooler---->{Will be placed in front of the radiator for maximum air flow and cooling with a mesh plastic bug screen in front of it to keep from bug plugage which would block air flow} (Drastically effect Efficiency)!

The addition of the RedLine D6 (100% Full Synthetic ATF) will be able to add the needed protection.

http://derale.com/products/fluid-co...0-plate-fin/190f-fan-switch-thermostat-detail

Once again! I say this way to many times. I don't post my projects for others to follow! I never recommend it. Every project is WELL researched and thought out! I am still so thankful I ignored the ones telling me the Hemi was designed around the 20wt oil. LoL! What a Hoot!
Anyway AMF this is your thread: I will play nice! Keep me up too date with what you find out about this goofy Heat Exchanger!

I still have not ruled out after this install adding a small fan in front of this new cooler. Install will be really easy since all I have to do is remove the grill which takes about 10 minutes.
This project so far is less than $100. In my eyes it's a very cheap investment to get my transmission temperatures down to at least a little blow 180°.

I know after watching Shawns first video at 40,000 miles and seeing the debris and some sludge already starting to build up in his transmission pan I know I'm doing the right thing by cooling off this transmission fluid . After he added his large Duramax transmission cooler his pan looked 100% better just from cooling off the fluid. With that said he also found a way to bypass the heat exchanger.

I myself do not have plans on going that far but it would be interesting to see how this rascal operates.
No matter what anybody says heat is not a transmissions friend. From my reading ram only installed this heat exchanger to help with fuel mileage.
I asked Todd(ZF Tech) about this and he informed me I was correct--->ZF had nothing too do with this add on, and didn't want to comment on it.
 

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AFMoulton

AFMoulton

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SyN you don't have to place nice here! LoL I like all kinds of posts. When I track it down I will def share!


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Rustycowl69

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I was coincidentally just looking at coolers, and I was impressed with how many different ones are available. One poster was concerned about engine oil temp as well as tranny fluid temps. and I noticed there were several coolers out there that have provision for cooling engine oil, and tranny oil at the same time in the same unit. And they are equipped with different cfm fans, which can be controlled with an in-line thermostatic switch. It is really a buyers market for these things
 

SyN

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Cooler and hoses and all parts have been ordered from summit. I will post pics of install as well as after install temps.

AMF: you think swapping to a 180*F thermostat would aid in additional temp drop of the trans fluid?

Here is a great fit for our 1500 w/8HP70!

https://jet.com/product/detail/2748...gclid=CPqUsM75gs8CFQyRaQodCqIKzw&gclsrc=aw.ds

A am still curious how this cooler is going to handle fighting the trans heat exchanger. I should have all the parts by the 11th and install by the 13th. Had to cancel cooler from summit! It was on back order for a week or more.
 
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charonblk07

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AMF: you think swapping to a 180*F thermostat would aid in additional temp drop of the trans fluid?

If your fan settings are adjusted accordingly it will kick the fan on sooner which would begin pulling air through the radiators faster which will also pull air through the oil cooler sooner so it should lower trans temps in cases where you're either driving slow enough for the fan to need to kick on or when the coolant temp starts climbing while under load.
 
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SyN

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Charon: Thank you! I won't worry about a thermostat I guess until I purchase a Diablo.

Good mounting info. I knew I read my info correctly!

After looking around the front and behind the grill. I might have to remove and deactivate these active grill shutters with Shawns mod he posted. (Maybe)! I don't know if I want to mount the cooler behind these shutters. I don't know what temp these dam things come open.

I would prefer a constant air flow across this cooler. Mounting it behind these shutters will not allow this. I will have to look at my options when I get the grill off. Cooler shipped today 9/9/16. Should be here on Tuesday 13th. I will install the next day and post pics as I go.
 

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SyN

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Finished the install this morning. Took her for a test drive on the highway. Highway temperature never got above 186. Intown was a different story temperature raised to 192 but never got any higher just like without the cooler.

I am assuming the new cooler is going to be fighting this stupid ass heat exchanger the whole time. Might have to figure out how to bypass the heat exchanger. I know Shawn did it but he never posted how he did it.

I need to find out exactly where the transmission fluid temperature sensor is and where it's getting the actual temperature reading at. And also I wonder how accurate it even is.

Anyway here are A couple of pics after the install. It will not let me post two pics in the same post for some reason.
 

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SyN

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Here is a close up.

I have a brand-new thermal gun arriving any day now. I will shoot the line coming out of the cooler just to see how much temperature drop there is.

I did remove the active grill shutters permanently. Which made for a lot more room and airflow now. I also did Shawns active grill shutter mod so I have no code show up.

I also installed a plastic mesh bug screen over the cooler just like the one protecting the a/c condenser & radiator. Bug plugage hurts efficiency.

The cooler is a Tru-Cool 24,000 GVW / 20,500 BTU. I could have gotten bigger. The one I posted above is the cooler I should have maybe gone with. It is a 28,000 GVW / 29,200 BTU for $20 more.

@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@

Just a little update: must of had quite a bit of air in the line today the transmission temperature never got above 180°. NO Leaks!

Also have decided to replace the Magnefine transmission filter with a spin on transmission filter kit should be arriving any day now. Will be using a Fram Ultra XG3600 to filter the transmission fluid. This will make for very easy(mess free) filter replacement.

Will post a pic after install. Filter replacement will be $12 less each time. While getting better filtration over 8X more Synthetic Media area. Over 99% efficiency @ 20 microns & 80% efficiency @ 5 microns. Plus flow is not sacrificed due too the synthetic media.

Now need to figure out what too schedule the service interval at.

Update: parts for spin-on filter are all in. Will install Monday 19th. I have Thought about using a hydraulic filter since the micron rating is much lower. Filter will hold a qt , so every filter change I will be adding a qt of Red Line D6. The first filter will probably be changed at the 10K service mile mark. I will switch to a Fram Ultra XG3600 which will be in service for 20K miles (Which is still probably over kill but it is Very Good Piece of Mind).
 

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SyN

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After the successful cooler install on my 8HP70 I decided to replace the Magnefine filter with a spin on filter for the transmission.

The Luber-Finer PH253 come with the kit. After 10K miles I will replace with the Fram ultra XG3600 & probably do a routine maintenance with yet around the 20K mile intervals. I am still trying to gather information to see if it is better to use a hydraulic filter in this application instead of a regular oil filter.

Also I figure about a quart of transmission oil will drain out every time I replace the filter so I will fill each filter with redline D6 transmission fluid before install which will hold right at a Qt.

Here are a couple of pics so far. Edit::::
Finished Product! no leaks anywhere will have to add 3 more neodymium magnets to the filter other then that---> All Done!
 

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SyN

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For some reason I can only post one picture per post so here is the reason why I chose the very robust redline D6 transmission oil.

I will continue to use the D6 transmission fluid for as long as I have this ram. I will do a pan drain and refill around the 40,000 mile mark and then at the hundred thousand mile mark I will drop the pan and replace with new pan and Refill with D6.

I want to say I did talk to my service manager before doing this. He thought it was an awesome idea it would only help extend the life of the eight speed. He knows the quality and the reputation of redline he uses it within his SRT-10 as well as his new Hellcat.
The addition of the spin on transmission filter is 10-15 times as efficient as the pan filters and the redline D6 is A full-blown synthetic compared to the semi synthetic lifeguard fluid.
 

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crash68

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Is that thread tape and red RTV silicone used on those fittings?
Hope the filtration you added catches the bits of that stuff that usually comes off the end of pipe threads.
There is Loctite 545 which is a hydraulic fitting sealant, no particles to break off and end up in valve passageways.
 

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