{122 7H322 Valve assembly — transmission cooler bypass (model dependent) } decribes a 'valve' and it looks like maybe right next to that rear banjo fitting.


I can't find anything for Ford but I just remembered I dug up some TSB's on a 94 Dodge van that I rebuilt the tranny in a few months ago and a TSB was listed for:
-----------------
A/T - Cooler Bypass Kit/Restricted Fluid Flow
NO: 21-03-95 Rev. A
GROUP: Transmission
DATE: Jun. 16, 1995
SUBJECT:
RWD Automatic Transmission Cold Temperature Cooler Bypass Kit
THIS BULLETIN SUPERSEDES TECHNICAL SERVICE BULLETIN 21-03-95 DATED APR. 14, 1995 WHICH SHOULD BE REMOVED FROM YOUR FILES. 1993 MODEL YEARS HAVE BEEN DROPPED. ALL REVISIONS ARE MARKED WITH AN **ASTERISKS**.
MODELS:
**1994-1995** (AB) Ram Van/Wagon
**1994-1995** (AN) Dakota
**1994-1995** (ZJ) Grand Cherokee
1994-1995 (BR) Ram Truck
SYMPTOM/CONDITION:
At ambient temperatures of -15 degrees F or below, vehicles equipped with auxiliary transmission coolers may experience a lack of transmission fluid flow to the transmission. At these low temperatures, the automatic transmission fluid might freeze in the transmission cooler lines restricting fluid flow. This can cause damage to the transmission, and in periods of extended driving, transmission failure may result.
DIAGNOSIS:
The cold weather by-pass kit should be installed if any of the following conditions are met:
1. If the vehicle is used in areas of extended cold ambient temperatures (below -15 degrees F).
2. If the transmission has failed in cold ambient temperatures, install the bypass kit when repairing or replacing the transmission. Follow proper cooler flushing and transmission replacement procedures found in the Dodge Ram Service Manual.
Note IN HOT AMBIENT TEMPERATURES, THIS KIT WILL DECREASE THE COOLING CAPACITY OF THE TRANSMISSION COOLING SYSTEM. AS A RESULT, UNLESS THE ABOVE STATED CONDITIONS EXIST IT IS NOT RECOMMENDED THAT THIS KIT BE INSTALLED.**
POLICY: Reimbursable within the provisions of the warranty.
TIME ALLOWANCE:Kit, Transmission Cooler Bypass 1994-1995 (BR)
Install 1994-1995 (ZJ)
1994-1995 (AN)
1994-1995 (AB)
FAILURE CODE: P8 - New Part
------------
I haven't been able to find a diagram for the valve but I have the part# 04798633 and adaptor p/n 04798634.
I don't know why "Note IN HOT AMBIENT TEMPERATURES, THIS KIT WILL DECREASE THE COOLING CAPACITY OF THE TRANSMISSION COOLING SYSTEM." But that has my curiosity.

Yeah, that 7H322 is the bypass tube ... and it uses the same Ford 'basic' part number as what the older "H" fitting I've been talking about.

You see, ford 'basic' numbers remain the same across all applications ... (Pinto to Heavy Truck) ... only the Prefix/Suffix changes. For example, the 'basic' number for a fuel tank is 9002 . The complete part nunbers might be something like D1FZ-9002-A for the Pinto, and D0HZ-9002-C for the heavy truck.

Basic numbers become like a second language to a Ford Partsmen.



I found a little more info on the Dodge one for you ... but still no picture.
http://home.sc.rr.com/janet/TSB/21-07-97.htm

This one DOES sound like it has both an orifice and a check valve, implying that a certain amount of fluid is being FORCED to bypass, rather than allowing fluid dynamics to control the flow ... as I imagine the low-tech "H" fitting to be?

Either way ... I suppose that just about ANY cooler by-pass system would DECREASE the efficiency unless it was, as you say, thermostatically controlled in some way.

I'm going to bookmark the NHTSA website ... even though the interface sucks a little, and they only seem to have 2002+ info

Duce is correct with his graphic, however the pluming that I have serves the purpose that I run very well. I mention that I am running a converter with 3400 of stall, keeping this in mind and realizing that most of the time when driving in traffic the RPM of a motor is mostly 1200 - 1800 , so that means I have some amount of stall until my motor reaches the drive parameter 3400. It seems to me that a need for the tranny fluid to be warmed through the radiator water becomes a mute point is the configuration ...... for the stocker types Duce's digram applies and Hayden is a great source of information and product. Just not the finial word or set up.

OK, here's the latest on that "H" fitting...

My first thought was what I now believe to be correct...
I was real CLOSE on the part number as well...
I originally thought it was E3TZ-7G118-A,
but it turns out to be E3SZ-7G118-A... which is now obsolete anyway

There is only one available at ONE Canadian Ford dealership (Metro in a suburb of Vancouver, British Columbia.)

The original TSB was number 82-22 released in late 1982.
I was not able to find the actual bulletin to get the actual text or any diagrams, etc... all that I can find in the Microcat catalog is a reference to that TSB.

Sorry for the "wild goose chase"

I have a switch pitch 400 Turbo in my 32 Roadster with a 800/2800 stall converter.......and that's the way I have mine run. except the cooler is NOT in front of my radiator.

I believe that the cooler before the radiator is the BEST way...at least for my car.. the extra cooler cools the fluid BEFORE it goes to the radiator....and helps the radiator cool even better......because the radiator then dissipates heat to the transmission fluid.....getting it back up to the recommended operating temperature recommended by MOST transmission people. The fluid needs to be warm to work the best...just not real hot.




This is another question that has MANY opinions and most will not be changed..... NO MATTER what is posted....
Like the eternal
1) 8 inch Ford is strong enough for a 350 HP engine
2) Model A frames are OK...boxed with no crossmembers
3) Mustang II suspensions are great for everything ( even 5500 lb. cars )
4) Aluminum VS brass radiators cooling effectiveness
5) Rubber lines VS hard lines for fuel and such ( transmissions too )
6) Holley VS Edelbrock.......carbs
7) exhaust manifolds VS headers....
8) stainless lines (37 degrees VS double flare )
9) Frame swaps are easy to do....and are possible for every car
10) Homemade wiring kits VS EZ wire VS Painles VS RonFrancis VS......

I could go on and on.....and I know you guys could add a bunch also but it's late.....I am going to BED...

.

For what it is worth I have had tired the cooler in front, then back of the radiator with a elect. fan on my 36 Chevy coupe with a 350/700r4 and I didn't see where it made a difference as to the heat built up. I ran it this was for over 12 years. Now I have the cooler mid way back under the car. Still no problems. I think as long a you have air flowing across the cooler you would be ok. Dan

That sounds sort of risky getting a tranny cooler from the salvage yard (there less than $20.00 new), how do you know the tranny in that vehicle didn't take a crap and that's why it's there in the junk yard. Then you put that cooler on your vehicle and run all the metal filings through your tranny NO!!.... NOT GOOD!!..... BAD BOY!! (LOL). In reference to the direction of fluid flow through the cooler , why does it make any difference what direction the fluid flows anyway, all the coolers are is just a twisty hollow tube, nothing different than a tranny line to or from the radiator Supposing you hook the lines one way or the other on the cooler, what difference does it make. It will still flow right. The only difference I see is that with the lines hooked one way, the fluid would travel through the cooler first, then rad. With the lines the other way it would flow through the rad. first, then cooler. BUT......depending on where you PUT the cooler, in front of,,, or behind the radiator(which is anyones discretion), it could heat OR cool first or last before returning to the tranny. Am I wrong on this?

Man, Don't use a junk yard cooler, For a few bucks more get a new one! Otherwise you may end up doing the cooler job twice. Also if you are going to put it on the radiator be real careful you don't punch a hole in the core. And it can happen as I did it once. Good luck on your project. Dan

Provided the cooler is not damaged, the lines that twist back and forth are smooth on the inside and should not trap any metal from a previous install that some solvent and some compressed air will not clean out. One of my auxillary coolers was previously an oil cooler on a 96 Chevy 3500 HD Diesel truck. That Deisel motor took a bad crap in the bottom end, but the oil cooler cleaned out easily with a can of brake parts cleaner and some compressed air.

That's the whole point discussed throughout this thread. If the ambient air temp is say 0 degrees, this can cause the fluid returning to the tranny to be TOO cool for proper lubrication and operation of the transmission.

I run 2 external coolers and also the cooler housed within the factory radiator. I previousl had the fluid lines connected so that the fluid went through the radiator first, then through the externals.
After reading this thread a few weeks ago, I switched the direction so the fluid goes through the radiator last.

Before:
I had an issue with the 2-3 shift feeling like the pressure plates are bouncing off of the friction disc at the first cold shift, and also like the 2-4 band is still being engaged momentarily by that apply circuit for a split second after the 2-3 shift. This issue has been mainly during the first minutes of 'cold-start-up' operation all summer, but now with cold weather, it is prolonged and even to the point of doing it continually in extremely cold conditions.

After the cooling fluid flow direction change:
It still does the same thing when cold, but the problem clears up quickly as the operating temperature rises and after the engine coolant is up to temp, it shifts fine, even when it's very cold outside.

This 2-3 shift problem is a result of extensive internal modifications to the tranny aimed at very quick and hard shifts {for the drag strip}, which the 4l60e is just not very fond of. Those modifications serve there purpose very well although this little 2-3 shift thing turned out to be a by-product. But it is very noticable, and gave me an excellent oportunity for an indication of the differences produced by the temperature of the fluid being returned to the tranny.

Wow. I learn a lot around here.

The point of a trans cooler is not to cool the fluid as much as you can. The point of a trans cooler is to keep the fluid from overheating/boiling. Trans-fluid should be 160-190 degrees, 175ish being just right. Keeping transmission fluid continually cold can cause severe transmission damage. The trans lines should be routed from the trans, to the cooler, to the rad, and back to the trans. The radiator will either cool or warm the ATF to operating temperature. This is why every manufacturer routes ATF through the coolant, to bring and keep the ATF to correct operating temp. If the point was just to cool the ATF, then we would have a thermostat in the trans lines. ie the point of coolant is to cool the engine, not warm it up, so we have a thermostat. (simplistically)

Some manufacturer's must be different, I just hooked one up yesterday on a '95 Jeep and the instructions said to go from trans, to rad, to cooler, then back to trans. It said hooking this way "provides maximum cooling by returning coolest fluid directly to transmission".

That is correct, "maximum cooling by returning coolest fluid directly to transmission" but in some circumstances this is not desired, especially if you operate your vehicle in northern Canada in the winter months at very cold temps. Your user information says you are in Wisconsin. I live in Mississippi and I'm sure it gets much colder there than it does here. If I can notice a difference in my shift problem that I posted about, with temps getting pretty cold for here, then I would think the advantage of the tranny fluid flow being routed opposite of that manufacturers directions would be a very good suggestion for me to consider for a vehicle operated in Wisconsin. I'm sure the fluid manufacturers also have some guidelines concerning use of their product at sub-freezing temperatures, although maximum cooling would likely not be included for suggested proceedures in those conditions.


I agree with your post and I realize this is being a little picky, but the thermostat in the engine coolant circuit is designed to do just that, warm the coolant to a temperature that is desired for proper operation. Without the thermostat, the coolant can stay at a temperature below what is desired, especially with a low ambient air temp as is discussed already throughout this thread, although concerning the transmission fluid instead of engine coolant {and you will take notice of this on a cold day when your heater is blowing cold air}.
Also, the idea of a thermostat in the transmission fluid cooling circuit is not a bad one, although there would need to be a bypass circuit routed with the thermostat in, to an extent, that flow path in order to open it when needed. But there is no need for this since the engine coolant thermostat can accomplish the same task, free of any other system needing to be involved, and at a temperature that is acceptable for this BUT the factor of cold fluid pump cavitation and lack of lubrication at low temperature would be better addressed by a bypass with short fluid travel distance because of the difficulty of pumping that cold fluid through extended line distance, just as Ford utilized, which was pointed out in previous post by Don, {66GMC}.
And arch, as I said, "don't mean to be picky", but the internet is dead tonight and I just felt like typing alot. But I do try to help when I can

plenty of good ideas and suggestions here.

as I often post , there really is no perfect answer for tranny cooling hook-up.

Your local weather will affect what type of cooling / warming you need in an aftermarket application: hotrod , race car, street machine, farm vehicle.

Liquid to liquid coolers offer the best heat transfer. Air to liquid function well, but MUST have air flow to operate.

I am not a fan of the coolers that "radiate" heat and are usually mounted to the frame member of the vehicle.... <---- read that as my opinion.

carry on the good discussion

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Be kind to your children... some day they may be decide what nursing home to put you in

Thanks for posting Crosley, and coming from the main source of valuable information I recieved when building my first 60e, I take your information as being experienced and very reliable.


Now about my John Deere...

This discussion has been added to the Transmission-Rearend Discussions category of the Hotrodders Knowledge Base.

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