T4R radiator design questions / Pink Milkshake

[Qyota]

You're right...no benefit other than cost. Cold trans fluid works just fine. I've never had a cold-related transmission problem in any car I've owned, and I've lived in northern Minnesota and Wisconsin my whole life. External cooler with bypass is the way to go. I'd argue that the bypass isn't even that necessary.

Will be installing my 4454 this weekend!

 

[BTO]

Cold trans fluid works just fine.

The theory is that colder fluid is thicker. Thicker fluid does not flow as well and due to that may impact lubrication. I wonder if there is any scientific data on this?

My point was that the radiator does not warm up the fluid any faster than a bypassed system and may in fact be much slower. You are saying it's a moot point.

 

[alp]

Repeating of my above post.

"Is orientation of cooler inlet/outlet ports important?
It looks like you used connectors to connect existing transmission in/out hoses to the smaller hoses supplied with the cooler. Am I correct?"

 

[twitchee2]

i got a tranny cooler out of 1 ton dodge for $25 at the local pick n pull. just waiting for the rain to stop so i can intall it. its 18x8x1/2in...its a BEAST

 

[Qyota]

My point was that the radiator does not warm up the fluid any faster than a bypassed system and may in fact be much slower.

And I agree with you on that. With my scangauge I can monitor water temp (as measured at the coolant temp sensor, which I assume is somewhere on the block) AND trans fluid temp (as measured on the transmission) at the same time. So, as I watch the water temp rise, the ATF also rises, but at a much slower rate.

What I'm getting at is, The transmission is creating it's own heat during warm-up driving, and is affected very little by the temp of the coolant in the bottom of the radiator (which is where the trans cooler is). The inclusion of the cooler lines in the radiator is for COOLING purposes, not heating. 190F coolant will draw heat away from 200F+ ATF under high-load circumstances (towing, uphill, high heat, etc.).

Basically, don't worry about how COLD the trans fluid is. It will warm up gradually just by driving, with or without a bypass valve.

 

[BTO]

Repeating of my above post.

"Is orientation of cooler inlet/outlet ports important?
It looks like you used connectors to connect existing transmission in/out hoses to the smaller hoses supplied with the cooler. Am I correct?"

Dana/Long (Tru-Cool) website says:

How should I mount the oil cooler fittings?
Fittings can be located up, down or sideways. This
advantage, plus their compact design, make installation
of our coolers quick and easy.

Hayden website does not specify. Only states, "position in desired mounting location". It shows a picture with the connectors at bottom.

I did a search and found this:

The mounting orientation of the cooler is VERY important. I called B&M on this, because I was not sure. The least efficient way to cool is by having the hose outlets facing down. The MOST efficient is to have the cooler mounted with the outlets up or on the side. If you choose on the side, make sure the INLET (from the factory cooler) is on the bottom and the top hose goes to the tranny. This is VERY important.

Edit: This last is what I'm going with side ports, inlet bottom. Sounds good.

 

[alp]

Thanks BTO for clarification!
I am going to use the same setup.

 

[240m3srt]

Repeating of my above post.

"Is orientation of cooler inlet/outlet ports important?
It looks like you used connectors to connect existing transmission in/out hoses to the smaller hoses supplied with the cooler. Am I correct?"

Ya know as far as orientation im not sure thats a great point you bring up...??

The fittings were supplied with the kit so i just used them to splice the stock hoses.

 

[BTO]

Doing the cooler install this weekend. How do you tell which line is the outflow and which is the return?

 

[Qyota]

Someone has a diagram somewhere. Or, you could just drive around for a while, then stop and feel both rubber lines to see which is hotter! ;-)

I installed my 4454 last weekend. Went pretty well. I'm getting some weird temp readings, though. I don't think the thermal bypass (internal) is working. Ambient temp was 32F, and driving down the highway within the first 5 minutes, the temp never got above 70F. But once things warmed up and I got into town, it was a little more reasonable with temps around 130F. I honestly don't know if this is going to provide enough surface area to cool sufficiently during the hotter months, or while towing on hot days. We shall see. Can always install a bigger one, I guess.

 

[alp]

I am planning to instal 4454 in 2-3 wheeks bypassing the radiator. As for know I am monitoring the ATF temperature of the original set up with a Scangauge. With 32 deg outside it takes about 5 local miles to get to 130 deg. 160 deg was the max highway temperature w/out towing so far.
I will report the temperature reading after installation of the cooler.

 

[240m3srt]

Doing the cooler install this weekend. How do you tell which line is the outflow and which is the return?

My understanding is you can hook the lines up to the oil cooler either way.

Does anyone think differently?

 

[Qyota]

The cooler doesn't care, but it's probably a tad more efficient to run the hot stuff to the top of the cooler, and have it exit the bottom (assuming you put the cooler on it's "side" with the inlet/outlet pointing to your passenger side). This is how the coolant radiator flows.

 

[alp]

Doing the cooler install this weekend. How do you tell which line is the outflow and which is the return?

On my 1999 SR5: looking at the radiator from the transmission the return port (back to transmission) is on your left.

 

[ryani]

I'm installing my 4490 tomorrow and I've read you should mount the cooler sideways and run the inlet to the bottom port of the cooler. From what I read that way you won't lose pressure through the cooler by the liquid "falling" down through it. It stays the same pressure if its being forced up to the outlet

 

[alp]

I'm installing my 4490 tomorrow and I've read you should mount the cooler sideways and run the inlet to the bottom port of the cooler. From what I read that way you won't lose pressure through the cooler by the liquid "falling" down through it. It stays the same pressure if its being forced up to the outlet

On the other hand locating the inlet on the top and outlet on the bottom will reduce the pressure drop thru the cooler due to the "help" of the gravity. Furthermore, this set up will help to force the cold ATF thru the bypass passage during worm up. Let the gravity work!
Any other opinions are welcome.

 

[Qyota]

I'm still not sure the thermal bypass in my 4454 is working. For example:

This morning it was 13 degrees in my garage when I started the truck. Backed out, and let it idle for about 1 minute. The ATF was initially 13F as reported on my ScanGauge II.
As the engine coolant warmed to about 60F, the ATF was still only 24F (makes sense, it's not doing any work to produce heat). I go the 3 blocks to get to the highway, and the ATF starts to climb. I'm stopped at the highway (55mph road) for a bit, so the ATF is now 70F. I merge into traffic and the ATF drops rapidly to about 58F and stays there (while I'm traveling 55mph in -2F temps) until I slow down in the 45mph zone (about 3 miles of driving). During the 45mph zone, the ATF climbs to about 90F. Then I'm back into a 55mph zone, and it drops back down to 70F. Once I'm in town, it rises to about 130F and stays there.

So...what's goin' on here? I would think if the bypass was working, I wouldn't see the huge swings in ATF temp when traveling at 55...even if the ambient air temp is below zero.

I might try installing the external in-line bypass to see if that makes a difference. I bought it when I bought the 4454, but thought I'd try it without first.

Note - the truck drove and shifted JUST FINE, even with the relatively cold ATF. So, maybe it's not even an issue.

 

[BTO]

From what I could gather, the bypass works off orifice size and cold thick fluid will go through the bypass.

How do you have the 4454 mounted? Maybe that has an effect on the bypass.

BTW, where is you temp sensor located? It should be in the outflow line from the tranny.

 

[alp]

I think that since you bypassed the radiator the chill factor has a big influence when you ride the truck on highway at sub freezing temperatures.
I think that at low temperatures the bypass is not effective enough to keep the fluid temperature steady. This will explain changes of the ATF temperature reading versus speed.

 

[Qyota]

My scanguage uses the temp sender on the transmission itself. I assume it is near the outgoing line. It's amazing to me how fast the temp reading can change in that location...you'd think it would be a little more stable.

I have my cooler mounted in front of the condenser and with the inlet/outlet directed to the passenger side. I believe I have the hot ATF entering at the top of the cooler.