How Did You Install A Trans Cooler On Your 1975 440 727

[LJ-TJ]

Any of you folks got pic's on how you installed a trans cooler on a 1975 440 727. Do you put it to one side? In the centre? Do you just bypass the radator and pipe it directly to the trans cooler it' self. Thanks in advance. The old girls been sitting on the shefl for the last few years and I'm trying to get here ready to hit the road again. Tranny was running a little warm the last time I took her out so thought I'd try to cure it.

[kenwautoone]

I just ran cooler by itself ( like on race car application).It is in center bottom of radiator.you might want to go crazy and get one from Summit,that has electric fan attached to it.I also have trans temp gauge in cooler line exiting the cooler.

[RockwoodMike]

Here is my setup..It goes to the trans without any connection with the radiator bottom tank hookup..

Mine is a 73 with the 440

[LJ-TJ]

Thanks Guys. My experiance and consern is sitting at the border waiting in traffic on a hot day. I've had to sit and watch the temp go up and could do nothing about it. Thanks again. keep the ideas coming.

[BigAlsVehicleEmporium]

After getting my radiator re-cored, I decided to not use the internal cooler. Since the rest of it was so bad, I didn't trust it to not leak coolant into the transmission and ruin it. I plugged the two 1/8" NPT ports in my radiator and ran a completely external cooler.



I went with a TRU-COOL MAX LPD4739-1 cooler as it was large, wide, and short. I wanted a good sized cooler, about the same width as the radiator, that wouldn't take up the whole height and rob too much cooling capacity from the engine. I paired it with a Derale 25011 oil thermostat to speed up transmission warmup times and keep it from running too cool in colder weather. This oil thermostat runs in bypass until the ATF gets to 180 degrees and then it flows through the cooler. I temped everything with an IR gun at several points during my latest 500 mile trip in the mountains at it never got above 185 F. The transmission cooler has 3/8" inverted flare fittings and the oil thermostat has 3/8" NPT fittings, so some adapters were required to interface with the original 1/8" NPT cooler hoses.

[LJ-TJ]

Now that's what I call a piece of engineering. WOW nicely done. I'm starting to get a drift of how you guys are doing things. I should have something in the works in the next day or two.

[Eyez Open]

Indeed that is quite a installation..busy is the word. Nice job well done..tinkeritis runs deep in you. Frankly I've just ordered that cooler the dimensions are spot on.

https://www.amazon.com/Tru-Cool-LPD47391-Pressure-Transmission-Cooler/dp/B0060NKA1U/ref=mp_s_a_1_3?adgrpid=127352099208&hvadid=631538319970&hvdev=m&hvlocphy=9032827&hvnetw=g&hvqmt=e&hvrand=597357447217816107&hvtargid=kwd-295617024929&hydadcr=25168_13572021&keywords=tru+cool+lpd47391&qid=1686014135&sr=8-3

[LJ-TJ]

Excellent, excellent examples. Thanks lads. This is what I came up with so far. The frame is made up of all bolted together 1-1/2 inch angle iron. The unit is bolted to the front cross member a head of the rad. Were I'm now having problems is there are two Inlets  on the upper left side (passanger side)and one on the upper (driver's side} Which side do I put the pressure side and on a 727 which line is the pressure line?

[BigAlsVehicleEmporium]

LJ-TJ,

On the transmission both cooler ports are on the driver's side. The front port is the supply port and the rear port is the return port. I first found this information on various Mopar forums, and then later confirmed it when I found Figure 11 on page 21-29 of the motor home factory service manual:



When you say there are two ports on the passenger side and one on the driver's side, are you referring to the cooler?

P.S. How are you attaching images to your post? I note that I can click your images easily to download them and I can see how often they've been viewed, etc. When I use the built-in forum tool to insert images, I don't get those options.

Thanks!
Alan

[LJ-TJ]

Hey Alan thanks for responding. What I'm trying to figure out is. If your standing looking at the front of the motorhome and looking at the trans cooler. On the top of the trans cooler on the left side is a port?.On the right side of the trans cooler up on top is a another port. Which port is the in pressure port and which is the out port.

[LJ-TJ]

This is the Trans cooler

[BigAlsVehicleEmporium]

Ah, gotcha! Coolers don't have dedicated in/out ports unless they have a built in thermal bypass, like the external one that I used in my installation. As long as your cooler is just a plain old cooler, you can use either as the in/out. To know if it has a thermostat I think you'd need to check the literature that came with with it when you bought it. If you don't have any, post more detailed pictures and we can see if it looks like it's got an internal bypass or not.

One more note! I'd install it with the ports at the top so it doesn't drain out when you shut the engine off. It looks like that's what you're doing already, so great!

[DaveVA78Chieftain]

Little more info from the Cooling section of the service manual

[LJ-TJ]

  WOW! Perfect. That's exactly what I was looking for. Project tomorrow..Hook up my trans cooler. Thanks a millon mate. Appreciate you time. T.J.

[Mlw]

P.S. How are you attaching images to your post? I note that I can click your images easily to download them and I can see how often they've been viewed, etc. When I use the built-in forum tool to insert images, I don't get those options.

This is done by using the image button in the taskbar. As far as I remember it was different in the past but images have to be online somewhere because it's nothing more then a link to your photo.



When you use Attachments and other options you are attaching the image to CWVRV. The advantage of this is that the image stays on, even when you give up the location where the image was at or have removed it, then showing a dead link in your post.

Next advantage is that you can have your own gallery page here on CWVRV with all photos of your RV in one place.

https://www.classicwinnebagos.com/forum/index.php?action=gallery;sa=myimages;u=16109

it's not working at the moment but i am in full confidence Oz will find the solution.

[Oz]

I think you can actually use the gallery. The problem is, the actual image files were lost when the site was migrated. I don't know how but, they were. I can't find any backups which have them.

The data, image references, titles and descriptions are still there.

The only way to replace them at this point is for members to re upload them.

There is another way but, it's extremely time consuming and I don't know how much I can get done.

I'm going to try to reconnect attachments first.

But, it would be great if anyone would try to statca new album or add a picture or two to see if that can be done.

[LJ-TJ]

  Well Lads and Lassies she's done. Well except the trial run and hooking up the fan. Thanks for all your help. You can see the coolingt hoses on each side of he fan. Under neath I had to do a little cobbling as I couldn't find a single barbed fitting so I had to put a few fittings togeather. But when I fired her up she didn't leek any were.One last question. I'm thinking of relocating my trans temp prob. Would you put it on the line with the tranny fluid going into the cooling rad or on the out side after it cooled off.  

[kenwautoone]

I would put it on the exit side of cooler,that way if your trans temp gauge is working correctly,you can see if you indeed have the correct cooler in. place.Again all the experience with trans coolers is learned from race car applications . The atf temp should run 10 ° hotter than engine oil temp.thus, going up hill coolant/ oil temp will rise as well as trans temp . coolant temp may run up to 220°... trans temp will be approximately 230°.Thats as hot as I want to see.Of course going down hill,temps should cool down quickly.The fan will help on both ends sitting in traffic.

[BigAlsVehicleEmporium]

In the pan is the best place for the transmission cooler probe because what you care about most is the temperature of the transmission itself and the bulk of your fluid.

Inline to the cooler is going to read hot and you'll see spikes as you go up hill, accelerate, etc. It really just tells you what's happening in the transmission at that moment and not how it's doing over all.

Inline from the cooler really just tells you how good of a cooler you have. If your transmission is running low on fluid or the flow to the cooler is restricted, everything will look fine on the gauge while your transmission tears itself apart.

OEMs put transmission temperature sensors usually on the bottom of the valve body so it is bathed in the fluid in the pan, for this reason. Similar to how a coolant temperature sensor is mounted to the engine block and not the radiator or one of the radiator hoses.

Added: I did a little more research and found a bunch of references on the internet to the rear servo test port being a factory location for a temp sensor for these transmissions. That's the 1/8" NPT plug facing rearward on the passenger side. I wasn't able to find any Chrysler literature that confirmed this or anyone who spoke up and said "Mine came that way from the factory!" so who knows how accurate that is. Haha actually one of the sources I found that suggested this rear port was a reply to a question you asked ten years ago! I love how long this site has been around. Thanks again for all the work it must take to keep it going Oz!

[Oz]

Awesome, TJ! Thanks to everyone who helped get him the info he needed.

 

[LJ-TJ]

Big Al thanks This is were I ended up putting the probe in the tranny. I believe that's the spot you were talking of.

[BigAlsVehicleEmporium]

Looks good! Have you tested it out yet? If so what temperatures are you getting?

[LJ-TJ]

Well the coup de grace. The cherry on top of the wipcream of the choclet sunday.Thanks to the excellent coaching. I installed a toggle switch with a light in it to indacate when the fan is on and off.   I haven't had a chance to check it out yet as a few more repairs are in order. However first chance I get I'll let you know how it works out. Thanks guys. The mantra of the site is the dumbest question you can ask is the one you don't ask. What I love about this site thanks to Mark and Dave and many others don't make you feel stupied no matter how simple the task. What a refreshing site.

[BigAlsVehicleEmporium]

That is an impressive assortment of gauges! Did you build that box yourself??

[LJ-TJ]

Yep! I didn't like the idiot gauges that the Winne had as well as they usually don't work. Plus I don't like looking down at the gauges when I'm driving. I wanted the gauges to be glancable. From left to right. Main Fuel, Aux Fuel,Volt meter,Vaccum gauge,Trans Temp,Water Temp,Oil Temp,Oil Pressure,Fuel Pressure and finally a Tach. All Auto Meter gauges from Craig's List and E-bay for a total of around $250.00