Searched and can't find definitive answer. 700r4. Will a SBC run cooler with a remote tranny cooler compared to running the cooler lines through a Walker radiator?
I use a remote cooler in both my car's. My only reasoning is that why rely on 180 degree radiator temperature to cool your trans. I don't know if anyone has done any research on this subject but I have never had a problem with a remote cooler.
I ran a remote trans. cooler under my 39 Chevy sedan, with a 350 SBC and 350 turbo trans. I had the regular Walker radiator, not the heavy duty Z series and it ran fine. I'm not a mechanic so I couldn't tell you the benefits of the remote cooler for a trans. but I always used a remote one on my street rods.
I have a Walker with the built in cooler at the bottom of the radiator, and an external cooler as well when I went to a higher stall converter I added the extra cooler to the bottom of the frame rail, a Ford pick up cooler like this http://www.ebay.com/itm/New-OEM-For...ash=item2a675a5b16:g:HcsAAOSwubRXLgkr&vxp=mtr
As it happens I did do an (unwilling) expeirment on this about 1990 .I had an OT nova with a considerably modified 250 in it and a turbo 350 with a 3500 rpm convertor.My first try at an auto in a hot rod type car,always ran sticks before that.I ran the cooler lines into the radiator.The car ran around 180-190 coolant temp.The trans ran about ten to twenty degrees hotter -too hot! I found 5 feet of 3/8" copper tubing,wound it into a coil and ran the trans cooler lines through it.Hung it on the firewall with zip ties on the passenger side where the AC\heater box used to be.Trans temp went down 20 degrees on the way home.This car had no inner fenderwells so there was a fair amount of air blowing through.Fitted a regular trans cooler after that and am a believer!!
On my auto trans cars with 350 or 700 R4 trans I run a B&M external cooler mounted along the frame rail combined with a Derale trans pan (the one with the tubes running thru the bottom of the pan) and have experienced no problems to date. I've done this on at least 1/2 a dozen 32's.
I was running a remote cooler on a 48 PU with a 200-4R and had over heating problems. I had a Walker radiator so I ran the fluid through the Walker and then through the remote and never had a problem again.
A perfect solution would be an external Trans oil cooler with a thermostatic control so that the oil can maintain a constant temp when you are dealing with low ambient temps. The at must maintain a minimum temp to operate properly. Much like a thermostatically controlled engine oil cooler. Different transmissions and different atfs have different comfort zones so I can't give a general temp range for all. Generally it is recommended that the plumbing is Trans to cooler then to the radiator and back to the trans, so that over cooled fluid will pick up some heat from the radiator.
If you're not in a frigid climate and not abusing the transmission by racing or mega-towing, it shouldn't make a lot of difference what method you cool your transmission and it's usually simpler and easier to use a remote cooler. I had always heard that the main reason the car manufacturers put the tranny cooling lines in the radiator was more to warm up the fluid in cold climates than just to cool it.
I always run a radiator with transmission cooler and a separate cooler as well. Based on advice from reputable transmission shops, the consensus is to run transmission coolers in a series, from pressure outlet of transmission through radiator first and then through an auxiliary cooler before going back to transmission. Firstly, the reasons for this is that if the transmission fluid is hot, it will be cooled more quickly and efficiently by the radiator. Secondly, if it is cool it will be warmed up and yes they can run too cool. When they run cool condensation that may be in the system remains there, NOT GOOD. The transmission needs heat for self preservation but not too much. If the fluid is too hot after it leaves the radiator it will be cooled by the auxiliary cooler before going back to the transmission. Auxiliary coolers needs to be mounted where airflow isn't impeded as it needs to dissipate or radiate the heat, air flowing through and over does the job. If stuck for space a small slimline auxiliary coolers with a fan as you propose is the go. In colder areas and on short trips, the transmission may not get hot enough to reach optimum operating temperature. By being routed through radiator firstly it will be heated to a better temperature. I checked my OT in the garage and this is the way the big manufacturers now do it. They spend $M on R&D so why not take advantage of their expertise, it's free. I wouldn't recommend just running an auxiliary cooler, my opinion, but definitely use your radiator. Why, because the transmission generates the second greatest amount of heat beside the engine. I always use coolant rather than water. It costs a little more but a lot more advantages. Water has contaminants that may lead to blockages and corrosion. Coolant also lubricates your water pump. A good radiator also helps. I personally prefer to run fluid line through the radiator first and then back through auxiliary transmission cooler. I've seen small air deflectors used to push air over and/or coolers in some instances where space is an issue. Don't have it too low so that you run the risk off loosing it due to road clearance issues. Last thing you want to do is grenade your transmission due to heat buildup and heat will kill them eventually. I've never been a fan of just a stand alone transmission cooler in isolation. Normal transmission range is between 180F- 250F with pan temperature @ 60mph being 180F. Any more that 20mins @ 300F and you could need some repairs. When towing a load the temp can easily rise to 250F. Good fluid is pink, red means used, Brown or with a red tint means too long. Temp fluctuation is normal however prolonged high temps will definitely shorten the life expectancy of your trans. For optimum performance change the fluid, purge the system and change the filter every 15k miles (24k klms). For longevity used a quality trans cooler. Make sure your TV cable is adjusted correctly at WOT on a 700R or you will cook it.
To answer the OP's question- I run a Walker with a 350/700r4 setup and the integral trans cooler with no problems in 35000 miles- I don't pull a trailer - never had heating problems of any kind- engine or trans
A Walker in my 46 Ford Convertible for twenty years in a car with a 350/ 350th combo and A/C in a car that couldn't be overheated. No need for an add on cooler. Walker is the best. Pricey but well worth it. Gary
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