Lets Talk Trans Coolers

small b&m tube and fin between the fmic and condensor through radiator then back to my derale which sits on the front lip of my fuel tank.I have no room in front with alky,hids,etc.I have 9.5 non lock and run hard.temps seem to stay under control for me.Never had fluid come out of overflow though.
 
SloGN-did you ever fix your issue with the fluid spitting out?

And did you ever wind up getting a cooler? If so which one?
 
The Setrabs seem really nice but they are 70-100% more expensive than other pretty decent coolers. Not sure if it is worth the $$. Doing some research on coolers now. A lot of things come into play with them i.e. non lock up, hi stall, radiator trans cooler connected, location of cooler, fan on cooler, climate, deep pan, HP of engine, synthetic transmission oil. The general consensus is that you want the tranny to run about 160*-180*, temperature reading coming from the pan. Even though I haven't seen any real evidence that running it cooler 130*-160* will harm it.
The TruCool 4590 that Steve V uses is a pretty kick a$$ cooler= https://www.amazon.com/Long-Tru-Coo...&qid=1542049319&sr=1-1&keywords=tru+cool+4590
as well as the Tru Cool LPD47391/4739= https://www.amazon.com/Tru-Cool-LPD...0060NKA1U/ref=cm_cr_arp_d_product_top?ie=UTF8
check out the reviews on them. Viagra in a nursing home wouldn't get better reviews. The 4739 has the cold bypass on it. However you would have to like the "front mount tranny cooler" look if get those. In general the 4739 is lowering temps 40-60* with no fan. That is pretty impressive. But it is pretty humongous too.
The Hayden 679 is pretty awesome too= https://www.amazon.com/Hayden-Autom...63&sr=1-1&keywords=hayden+679#customerReviews
any 1, 2 or 3 star review is due to the fittings or hoses, so I would plan on getting quality ones.
 
Here's my current solution. B&M's biggest cooler on the left, another one for engine oil on the right, and you can see the Derale power steering cooler on the far right:

7RSEwJXtHwSaFE3onimotTzgV7iMdyzLRRXRbmCWwrRXFM3v_ZXjeXVc8iGjbp_AcuC3PCgv6imjPi5F2mtmCBp-iYYNNXwbtY34ThtyATSN5FS6NyOEJC5V1ukv6IY-Tcug4zB2Wag=w2400


This is what temperatures looked like at LVMS last weekend:

1542052739225.png


Now, the transmission loop in the radiator is still hooked up. What happened was the transmission temps were stable for two laps until the water got above 200, then the transmission started climbing rapidly, trying to reach equilibrium with the water. It climbed much less rapidly than the last time, since I've removed the engine oil load from the radiator. Which is good. The oil cooler was a good idea.

My next move is to disconnect the transmission loop in the radiator and get all three systems independent of each other.

The other concern is the water temp. Why is it climbing so much? This course was completely flat, so I'm not working the torque converter much. There's only two high speed sections, but digging into the data, the temps climbed during everything. The trans temp would rise while I had my foot in it, then start falling off as soon as I started braking and turning (the bumps in the green line). That's what I want to see.

The engine oil stabilized at 240 late in the session, which is perfect.

But the water temp just kept climbing. The radiator couldn't shed the heat, and I've got the big one GNS sells with the dual 1300cfm spahl fans.

The answer is airflow. The engine bay is getting pressurized and enough air isn't flowing through the radiator core. I can see it on the highway. In traffic, the car runs right at 160 all day long. Once I get on the highway rolling 70, the temperature climbs to 180. I'm non-lockup, but at 70 on the highway, I only have 1-2% converter slip and the transmission is running at 140.

The only explanation is lack of airflow through the radiator at speed. GM figured this out back in 1986. It's why McLaren put the fender vents on the GNX. Removing the weather strip at the base of the windshield helps below ~40mph, so keep that in mind if you're out somewhere and need to limp it home. Above ~40, a high pressure zone forms at the bottom of the windshield and starts packing air into the engine from the top, so don't remove the weather strip if you're going to be on the highway.

I'm getting a vented fiberglass hood over the winter. The ground wire for my fans also showed some heat damage, indicating the fans are sinking a LOT of current, which means they might be on the outs. My hope is a vented hood and replacing these fans with newer units should finally solve my three year battle with heat in a track application.

As for the dipstick. Get rid of the stocker. Lokar sells a locking dipstick. I use that, plus I attached an overflow can to the vent. If you overheat it and the fluid boils, it's going to come out the vent until you overpower that, then the front pump seal or the tailshaft seals will fail. Which are bad, but you won't have a fine mist bursting from the dipstick tube at the top of the motor and catching fire on the manifolds, which actually happened to me. You'll get a prodigious leak that'll come out in spots far enough away from the exhaust to not catch fire.

My case is extreme. I'm flogging the car hard for 15-20 minutes at a time. Not ten seconds. A drag and street car should not be having heat issues unless something's wrong, even with good condition stock equipment.
 
A good cooler and a catch can. Most overfill by 1 quart and at max rpm and temp some comes out the drain. This little can works. BTW this is actually in the NHRA rule book as a must have but there sight is not easy to navigate.
 

Attachments

  • overflowbottle.jpg
    overflowbottle.jpg
    70 KB · Views: 71
Had the same thing happening for me.
Some time ago, a local guy made me one of these for my car & all I can say is "it simply works"! :giggle:
 
I'd get your coolant temps in check before bypassing the trans cooler in the rad. They really are a good idea. Your fans are definitely suffering from something so start there IMO. I know your situation is different than most but I'd leave it hooked up.

At least you have data to keep track of it. So you'll know if you made a change for the worse. Keep us posted
 
agreed always want run the transmission fluid through the radiator cooler first then through the aftermarket cooler
 
At least you have data to keep track of it. So you'll know if you made a change for the worse. Keep us posted

Yup. Data is key. Everybody should at least have a Powerlogger if you're going to modify these. Actually knowing what it's doing saves time and gobs of money over trial and error.

And yes, I'll keep everybody posted. It'll probably be May before I'm back on track, but I'll update then.
 
The radiator transmission cooler does 2 things. It brings the tranny fluid up to temp in cold climates and it brings it down to temps (radiator temp) to cool it. If you live in a warm climate (not near freezing) there is absolutely no need for it. All you would be doing is introducing heat (radiator coolant temp) into the tranny fluid. Water is a WAY better heat transfer than air so it does a good job of cooling transmission oil that is ABOVE COOLANT LEVEL. It can’t cool it any lower than coolant level. But in Turbo6inKY’s case the radiator tranny cooler is verified as bringing up the tranny oil. Look at his #’s- the tranny fluid is 9* from his coolant temp. I don’t think that is a coincidence. So his tranny cooler is only removing 9* of heat. That is not a good # for such a cooler.
Bypassing the radiator tranny cooler would most likely lower his coolant temps because he is taking a substantial heat source away from the radiator.
In all reality if you are driving your car like a raped ape for 15 mins in Nevada weather, I don’t think all your coolant #’s are that bad. I do agree it seems you you have some fan/wiring issues though. Check you fan, make sure your radiator is baffled, put RMI in there, take the tranny oil out of the radiator, make sure your radiator cap is good, and think about getting a better water pump and overdrive pulley for it if you don’t already.


And SloGN-did you ever fix your issue?
 
In all reality if you are driving your car like a raped ape for 15 mins in Nevada weather, I don’t think all your coolant #’s are that bad. I do agree it seems you you have some fan/wiring issues though. Check you fan, make sure your radiator is baffled, put RMI in there, take the tranny oil out of the radiator, make sure your radiator cap is good, and think about getting a better water pump and overdrive pulley for it if you don’t already.


And SloGN-did you ever fix your issue?

I didn't even think about the stupid pump. What I've got on there is a parts store unit. Looking at the charts again, the temp climbs in the squiqqley bits, but levels off on the straights when the RPM is high, so I've got a mid-low RPM circulation problem. Duh!

Off to Summit! Thanks for the extra eyeballs!
 
The radiator transmission cooler does 2 things. It brings the tranny fluid up to temp in cold climates and it brings it down to temps (radiator temp) to cool it. If you live in a warm climate (not near freezing) there is absolutely no need for it. All you would be doing is introducing heat (radiator coolant temp) into the tranny fluid. Water is a WAY better heat transfer than air so it does a good job of cooling transmission oil that is ABOVE COOLANT LEVEL. It can’t cool it any lower than coolant level. But in Turbo6inKY’s case the radiator tranny cooler is verified as bringing up the tranny oil. Look at his #’s- the tranny fluid is 9* from his coolant temp. I don’t think that is a coincidence. So his tranny cooler is only removing 9* of heat. That is not a good # for such a cooler.
Bypassing the radiator tranny cooler would most likely lower his coolant temps because he is taking a substantial heat source away from the radiator.
In all reality if you are driving your car like a raped ape for 15 mins in Nevada weather, I don’t think all your coolant #’s are that bad. I do agree it seems you you have some fan/wiring issues though. Check you fan, make sure your radiator is baffled, put RMI in there, take the tranny oil out of the radiator, make sure your radiator cap is good, and think about getting a better water pump and overdrive pulley for it if you don’t already.


And SloGN-did you ever fix your issue?
 
The radiator transmission cooler does 2 things. It brings the tranny fluid up to temp in cold climates and it brings it down to temps (radiator temp) to cool it. If you live in a warm climate (not near freezing) there is absolutely no need for it. All you would be doing is introducing heat (radiator coolant temp) into the tranny fluid. Water is a WAY better heat transfer than air so it does a good job of cooling transmission oil that is ABOVE COOLANT LEVEL. It can’t cool it any lower than coolant level. But in Turbo6inKY’s case the radiator tranny cooler is verified as bringing up the tranny oil. Look at his #’s- the tranny fluid is 9* from his coolant temp. I don’t think that is a coincidence. So his tranny cooler is only removing 9* of heat. That is not a good # for such a cooler.
Bypassing the radiator tranny cooler would most likely lower his coolant temps because he is taking a substantial heat source away from the radiator.
In all reality if you are driving your car like a raped ape for 15 mins in Nevada weather, I don’t think all your coolant #’s are that bad. I do agree it seems you you have some fan/wiring issues though. Check you fan, make sure your radiator is baffled, put RMI in there, take the tranny oil out of the radiator, make sure your radiator cap is good, and think about getting a better water pump and overdrive pulley for it if you don’t already.


And SloGN-did you ever fix your issue?
not to get into a huge disagreement discussion but that's actually bass-ackwards when you live in a hot climate you have to have the radiator in line with the trans cooler and then through the aftermarket cooler because if you don't when you're sitting still or moving through slow traffic if you just run it through a regular aftermarket cooler you're getting no air flow across the cooler unless you have one with the fan then your temperatures will Skyrocket of course you guys can do what you want to but that's coming from somebody that's owned a transmission and hot rod shop for 15 years I've seen a bunch of it and I live in the South where it is a hundred degrees plus every summer also a good operating temperature for the transmission is the exact same as the coolant temperature so they're a match made in heaven the engineering guru's did a good job on that if you want to drop your operating temperatures in the transmission try running a couple bottles of platinum lubegard it should help just as I need a GN said fix your Cooling issue in the engine first good luck
 
not to get into a huge disagreement discussion but that's actually bass-ackwards when you live in a hot climate you have to have the radiator in line with the trans cooler and then through the aftermarket cooler because if you don't when you're sitting still or moving through slow traffic if you just run it through a regular aftermarket cooler you're getting no air flow across the cooler unless you have one with the fan then your temperatures will Skyrocket of course you guys can do what you want to but that's coming from somebody that's owned a transmission and hot rod shop for 15 years I've seen a bunch of it and I live in the South where it is a hundred degrees plus every summer also a good operating temperature for the transmission is the exact same as the coolant temperature so they're a match made in heaven the engineering guru's did a good job on that if you want to drop your operating temperatures in the transmission try running a couple bottles of platinum lubegard it should help just as I need a GN said fix your Cooling issue in the engine first good luck

You're not really disagreeing. Your application experience is different.

In my case, the water temp is coming up faster than the trans temp. The two systems will strive to reach equilibrium, so once the water temp exceeds the transmission temp, the water starts pulling the transmission fluid up. I had a much worse issue when the engine oil cooler loop was hooked up. The oil is perfectly happy at 240-250, and once it got there, it started pulling the water up even more quickly than in the charts above. Left to its own devices, then whole system would probably reach equilibrium somewhere between 220 and 250. That's fine for the engine oil, but it's too high for the water and transmission.

Now I've got an external transmission cooler in front of the radiator that's been boxed in. So when the fans are on, I'm getting air across the core. In fact, the transmission temps fall faster than the water the car is sitting still (the Y axes in the charts aren't the same scale for each data series, so ignore what the curves look like compared to each other), which reinforces the need-a-better-pump train of thought.

The cooler I bought is advertised by B&M as being enough for a 27,900lb GCVW truck. Until that water gets up around 200, the transmission fluid stays right around 140. Which means when the water's at 160 like it should be, the loop in the radiator is bringing the transmission oil up (or down) to 160, then the extra cooler is pulling 20 more out.

I should be able to separate it from the radiator and be fine. At least that's the hypothesis. I'm going to test it, and I've got enough instrumentation in the car to see if it works or not. It's easy enough to switch between the two.

But you're also right: If I get the water temp under better control, it's a moot point. I can leave it hooked up.
 
yeah I'm with you I didn't mean to sound like a know-it-all that's why I mentioned the seatrab coolers as this is what all the NASCAR guys use and I have put on some of my customers cars they are pricey but better than melting down your unit anyway hope you get it figured out but I would try a couple bottles of that Platinum Lube guard it actually works great has a friction modifier and also cooling properties one of the head Engineers that used to work at mobile one is who designed it anyway good luck
 
Also something else you might try is putting a higher pressure radiator cap on your system you might contact whatever Radiator Company you bought from but this works a lot of instances also
 
How about the tranmission lines? AN6 vs the stock size? Any opinions there? How about when the stock fittings are used in the trans case vs the AN adaptors?
 
I swapped to AN-6. Easier to deal with than trying to cut, bend, and flare the hard lines to deal with changes.
 
Top