Transmission oil cooler

[RVTRKN]

I took her on a second test, this time the trans was at 200*, after driving all over SoCal at 100* ambient without the cooler running. The test was to climb Cajon pass with the trans cooler running continuous for the entire climb, then run flat for a few miles then descend Cajon pass. It was impressive, from the 210 to the 15/215 junction, the start of the pass, the trans temp climbed to 215*. Here are the temperatures as I drove with the cooler running continuos until the last report.

The Climb
Trans Temp / Ambient Temp / Location

215* / 97* / 15/215 Junction
195* / 94* / hwy 138 Under Pass
189* / 90* / The Summit

Flat Running

182* / 89* / hwy 395 Under Pass
160* / 94* / Victorville ( Roy Rogers Exit) turned around
162* / 89* / Summit

The Descent

155* / 89* / hwy 138 Under Pass
146* / 92* / 15/215 Junction

I only had one rise in temp and that was due to a slight climb from Victorville to the Summit. I wanted to run the Cajon for a second pass to see what the temperature would run at with the trans temp at 146*, but it was late and the ambient was cooling down. Besides, I was going to have to get more fuel so I ended the test and turned off the cooler. As I drove the slight downhill run from the 15/215 junction, my trans climbed in temp ever so slowly indicating that the oil had cooled the trans as well, not just cooling the oil.

 

[TMorgan1]

I did a search and found your wonderful informative post. I have a 2001.5 with the NV5600 and have tried different fluids etc. to eliminate the hard shifting and read a lot of posts related to the problem of shifting. I finally realized on my last trip that my truck shifts fine when cold but not hot. Is this the reason you have installed the cooler and I don't recall what fluid you were running. Did you use the 50 wt. that was mentioned or did you use some ATF like fluid? What was the source of your pump? I realize I have a lot of questions but this is wonderful what you have done and I would like to duplicate it on mine. Thanks for the post!!!

 

[RVTRKN]

Actually it's the opposite issue, the G56 has an aluminum case which has a history of stretching when hot. There are trans coolers you can attach to the PTO covers, (Geno's garage sells them, and is where I bought mine) but don't seem to work as well as I expected. I considered buying a girdle for the trans that's supposed to help in preventing it from stretching, but a thousand dollars for it changed my mind. As in my posts I have posted about, I've seen as high as 250*, and that's just towing at 15K GCVW. I didn't know what the temps were before the SMF conversion, but after having to replace the browned bearings, it was getting hot in the stock form. So I wanted to see about installing what I ended up with and found a thread started by member "Schmalda" that installed a system that I installed but I improved upon it.

The oil I went with after the SMF conversion and transmission inspection was Mobiltrans SHC DC oil, which is susposed to be the authorized oil by Mercedes Benz, but when I went to over fill the trans by one quart, I saw brass floating in the oil which means the syncronizers didn't like it. So I went with a concoction that member "Ckelley1" uses which is Mobil manual trans 50 and Royal Purple Synthetic sycromesh.

The pump is a Tilton pump http://tiltonracing.com/wp-content/uploads/2013/07/Oil-Cooler-Pumps.pdf and is noisy but as you saw the numbers it seems to work well, just don't run it when stopped at a signal, people will be looking around for the noise their hearing.

The picture I posted has all the components I used, except for the transcoolers that I tapped into for the plumbing, they were already there when I started the cooler project.

 

[RVTRKN]

Ok, got some more info to report, 250 mile trip and that includes climbing Chiriaco Pass pulling my Boat. (15K GCVW) I ran the cooler continuos at 85* ambient on level HWY cruising 65 mph through Plam Springs and Indio and I started climbing the pass with the transmission temperature at 135*, it only raised to 150* to Chiriaco Summit. While running flat again at the top at 75* ambient, I turned pump off and it climbed to 185* by the time I got to Desert Center. Then I ran the pump again and took HWY 177 with a gradual climb to the 62 junction up to that summit and it cooled back to 150*, and the rest of the trip to Parker it went back to 135*.

That is impressive temperatures for my G56, I can only imagine what temperatures it ran at in stock form, but the browned bearings says it all. It was worth the money and time I spent researching the project and installing it. The only negative is that the pump is noisy.

 

[RVTRKN]

BTW, I only ran in 6th gear on purpose for running at maximum temperature. Normally, when towing I climb all grades in 5th gear as recommended for the NV5600 and the G56.

 

[bzingre]

Great project. My NV5600 gets hot when pulling the 5th wheel. I'm probably not doing any favors in OD at 22k, but we're screaming in 5th gear. Temps at 90F+ climb to 225 and keep going. Downshifting cools it down, but I want to keep mileage up and rpm down. Like your set up. Did the cooler bolt in without mod? Also, how did you plumb the bypass and check valve(s)? Any feedback after a year of use? Also, what was the approx overall cost? Nice set up!

 

[RVTRKN]

The OEM automatic heat exchanger will bolt up to your radiator, as its the same radiator as used for both the auto and manual equipped trucks. The OEM heat exchanger has a built in temperature bypass, although I turn off the pump when the trans cools down to @160* and on when @190*. It's been two years now that I have ran this setup, and it has worked flawlessly. However, because it is between the intercooler and radiator it will actually raise the oil temp passing through the exchanger when climbing steep grades heavy (23K), with boost at 25psi+ picking up heat from the intercooler. If I were to do it again, I'd purchase the BD oil cooler and bolt it up under the bed to eliminate this issue. It's only done it once, climbing the steep grade on hwy178 from Baker Ca. to Pahrump NV. But that's the only negative as to where its located. I can't imagine what the temperature of the auto equipped trucks raise in temps, but I saw mine raise 10* in a short amount of time, before I turned it off. Here's a link to the BD cooler.
https://www.dieselperformance.com/shop/product/xtruded-trans-oil-cooler-5-8-inch-cooler-lines-582

 

[Randomrunner12]

RVTRKN,

Any chance you have part numbers laying around for this? I'm looking to do this when I install my torque shield and hoping to do everything together.

 

[RVTRKN]

I'll try to post what numbers I have tomorrow, been busy lately.

 

[RVTRKN]

Oil Cooler: Sample only, you need to decide which brand and price, I don't remember who I bought mine from.

http://www.ebay.com/itm/Transmission-Oil-Cooler-NEW-for-03-09-Dodge-Ram-Pickup-Truck-5-9L-Diesel-/310738001037?hash=item48596d9c8d

Pump: Tilton 40-527 continuous duty, this pump is noisy, however it works great, manufacture confirmed they run noisy.
http://tiltonracing.com/wp-content/uploads/2013/07/98-1902-Premium-Oil-Cooler-pump.pdf
http://tiltonracing.com/wp-content/uploads/2013/07/Oil-Cooler-Pumps.pdf

Filter housing/mount: Moroso 23760

https://www.summitracing.com/parts/MOR-23760/

Oil filter: Purolator L14006

http://shop.advanceautoparts.com/p/purolator-classic-oil-filter-l14006/5792045-P

Hose: Russell Proflex

http://www.russellperformance.com/mc/hose/proflex.shtml

Notes: I used Russell AN fittings for all connections. I used trans coolers from Genos, but if I were to do it again, I would weld the proper size bungs on the PTO plates for the temperature senders and the AN adaptor fittings. With the pump and cooler, theres no need to buy the trans coolers from Geno's. Also I would probably buy the cooler from BD. I found that when climbing heavy and running at a high boost pressure in high ambient temps, the heat coming off of the intercooler will transfer into the cooler reversing the effect in which I just shut the pump off until I've reached the summit. Here is the BD cooler I'd buy.

https://www.dieselperformance.com/s...ission-cooler-kit-universial-1-2in-tubing-583

The reason is for the fact you can hide it under the bed and the fan can cool in Idle conditions, and it wont pick up any heat from the intercooler. If you PM me your phone number I can call you and explain in detail the process I went through if you like.

 

[truckmen]

Well its all done now, except for the electrical, and might I say WOW what a difference. For the frist test drive, I was climbing Cajon at 85* ambient and the trans was running at 200* and still climbing in temperature after only 20 miles of warmup before the climb. Running the pump for just 1 minute, my temperature droped 10*, then I allowed the temp to climb back up to 200* still climbing the grade and just as I reached the summit I ran the pump again for 1 minute and kept the temp at 195*. This was to allow the Thermostatic bypass in the transcooler to stay open allowing any remaining air traped from the first fill. I used the pump to fill the trans and the pump pushes the oil through the cooler first, then the oil goes to the transmission, but I was afraid that some air was trapped in the cooler due to the bypass. I turned around in Victorville because of the slow climb back to Cajon, that would allow the trans to climb in temperature again, once I crested Cajon I let the trans run at the normal temperature, seeing how its now on the descent, and it maintained 196*. When I reached HWY138 I then allowed the pump to run for slightly more than 3 minutes and the temperature dropped 25* from 195* to 170*.

I'm able to see both sides of the transmission temeratures with sensors in both coolers, and the passenger side runs 5* cooler when pressure is applied to the transmission climbing grades, empty or not. So I plumbed the oil lines to take the oil from the drivers side then return the oil to the passengers side. I saw a 45* delta temperature, meaning the difference between the passenger side (145*) and the driverside (190*) as the drivers side started to drop drastically to 170* from 195*.

I need to pull the 5ver, to know the real abiilty of the transcooler, but after a couple of years of seeing well over 200* on a mild day and 165* when at 40* ambient, the average is to high of a temperature and is why I was so interested in a transmission cooler. I saw 230* pulling my boat on I 10 north bound on the ascent out of Palm Springs at only 85* ambient temperature. I might pull the boat tomorrow for a hundred miles then climb Cajon with the pump running only when climbing Cajon.

I was only going to plug the pump into the cigarette lighter when I wanted to run it for the test, but the pump requires a minimum of 16 AWG stranded wire and a 10 amp fuse, so I wired it with a switch laying loose on the floor, with a 10 Amp fuse at the battery. I'll clean up the wire and install the switch next to the EB button at a latter date

I can say it was worth the money and trouble I went through installing this setup, and highly recommend all G56 equiped truck owners to consider installing a cooler.

Fantastic post! Thanks so kindly for sharing with us. I am very interested in doing the same.

Ralph

 

[e8888]

Oil Cooler: Sample only, you need to decide which brand and price, I don't remember who I bought mine from.

http://www.ebay.com/itm/Transmission-Oil-Cooler-NEW-for-03-09-Dodge-Ram-Pickup-Truck-5-9L-Diesel-/310738001037?hash=item48596d9c8d

Pump: Tilton 40-527 continuous duty, this pump is noisy, however it works great, manufacture confirmed they run noisy.
http://tiltonracing.com/wp-content/uploads/2013/07/98-1902-Premium-Oil-Cooler-pump.pdf
http://tiltonracing.com/wp-content/uploads/2013/07/Oil-Cooler-Pumps.pdf

Filter housing/mount: Moroso 23760

https://www.summitracing.com/parts/MOR-23760/

Oil filter: Purolator L14006

http://shop.advanceautoparts.com/p/purolator-classic-oil-filter-l14006/5792045-P

Hose: Russell Proflex

http://www.russellperformance.com/mc/hose/proflex.shtml

Notes: I used Russell AN fittings for all connections. I used trans coolers from Genos, but if I were to do it again, I would weld the proper size bungs on the PTO plates for the temperature senders and the AN adaptor fittings. With the pump and cooler, theres no need to buy the trans coolers from Geno's. Also I would probably buy the cooler from BD. I found that when climbing heavy and running at a high boost pressure in high ambient temps, the heat coming off of the intercooler will transfer into the cooler reversing the effect in which I just shut the pump off until I've reached the summit. Here is the BD cooler I'd buy.

https://www.dieselperformance.com/s...ission-cooler-kit-universial-1-2in-tubing-583

The reason is for the fact you can hide it under the bed and the fan can cool in Idle conditions, and it wont pick up any heat from the intercooler. If you PM me your phone number I can call you and explain in detail the process I went through if you like.

Did you end up needing any check valves?

 

[RVTRKN]

No check valves needed, IF you install the leaving and returning lines below the oil level. Once the heat exchanger fills with oil and you’ve corrected the oil level in the trans, the oil can’t drain from the exchanger. Unless there is a leak in the heat exchanger or lines above the oil level, it won’t drain.

 

[e8888]

No check valves needed, IF you install the leaving and returning lines below the oil level. Once the heat exchanger fills with oil and you’ve corrected the oil level in the trans, the oil can’t drain from the exchanger. Unless there is a leak in the heat exchanger or lines above the oil level, it won’t drain.

Thanks RVTRKN I plan on doing it just how you have, even with the PTO covers. I have an auto now and already have the BD Xtrude cooler, and also have a cooler upfront. But my cooler is out of a 2009 and doesn't have the thermostat in it. Now I'm just contemplating if I want to keep the one up front like I have it now, or just take it out and just run the BD under my bed.

 

[RVTRKN]

If your planning to change from Auto to manual, your BD cooler is all you need. The bypass in the front cooler is in my Heat exchanger as well , as they are part of the OEM setup. However you will be manually cycling on temperature anyway (unless you set up a separate control to cycle it on temp automatically) and wont need the bypass. The Factory bypass recirculates the oil back to the trans when under 135*, or so I was told, but you should let it get to 180* before you turn it on.

 

[e8888]

If your planning to change from Auto to manual, your BD cooler is all you need. The bypass in the front cooler is in my Heat exchanger as well , as they are part of the OEM setup. However you will be manually cycling on temperature anyway (unless you set up a separate control to cycle it on temp automatically) and wont need the bypass. The Factory bypass recirculates the oil back to the trans when under 135*, or so I was told, but you should let it get to 180* before you turn it on.

I definitely trust you and will be only using my BD cooler under my bed, but just FYI the factory cooler you have has a thermostat inside that square part that's on the top right. If you remove the c-clip and use a torch it pops right out, it sends oil back to the trans under 150°F and above that it pushes through the fins. The one I have is off of an 09' which doesn't have a thermostat, so it always pushes oil over the cooling fins.

 

[e8888]

I also want to use a Flex-A-Lite controller P/N 31174 to activate both the pump and the fan. what temps do you like to keep your trans in between? I live somewhere around you as I've driven through Victorville and into Randsburg. If you want to PM I'll talk more about that.

 

[RVTRKN]

That’s what I was referring too, was the bypass on the automatic trans heat exchanger that sends oil back below 135*. I like to run my temperature between 160* and 180*, so the bypass is not a factor. If you remember, my heat exchanger is for the auto equipped truck and my truck has always been with a manual.

I’ll be relocating to Vegas real soon, I’m already living out of my 5ver there, and by June of this year, our household and family will be completely moved in.

 

[MichaelOverfield]

Here is my version, it is under the cab, above the frame rail lower edge. There is a thermostatically controlled fan, and pump. I added the filter as well. Pictures on my thread. Questions do ask, I don't have run time as yet, since I have a couple other of projects ongoing before the truck is back on the road.

https://www.turbodieselregister.com/threads/g56-transmission-cooling-system.264234/

 

[e8888]

Did you ever end up using a thermostat to turn the pump on and off? I’ve thought of using this Flex-A-Light controller on a relay.