Automatic Radiator/ Oil Cooler

[Phoenix]

I have an automatic radiator for my GT, that I was wondering if you could use the trans fluid cooler as an oil cooler on my 4-speed? Would there be a problem using a newly recored radiator for this function and just run the oil through it rather than the trans fluid since I don't need it? Would it be effective? Just trying to make use of what I have and use the otherwise useless space.

[blancojp]

We have done this before on old Fords however you will need a good pump to send the fluid to the radiator. Also bear in mind that manual transmission oil is 90 weight, same as the rear end and very hard to pump when cold.

You could use it as an engine oil cooler but the gain is nothing to write home about.

[soybean]

Here is a good thread to read oil cooler install. I got one from a friend of Peters on the Volvo board. Much like ours here. Hth, Jarrell

[Phoenix]

Engine Oil was what I had in mind. I know I could run an independent oil cooler but it's basically aready built into the automatic radiator. There wouldn't be that much more space in the bay being used and it would make use of that function for the radiator.

[heimue]

Engine Oil was what I had in mind. I know I could run an independent oil cooler but it's basically aready built into the automatic radiator. There wouldn't be that much more space in the bay being used and it would make use of that function for the radiator.

Tony,

now that makes much more sense than cooling down the oil in the gear box. Go for it!

Dieter

[namba209 (R.I.P.)]

Don't forget you may need an extra gallon of oil to fill the cooler tank. I think a previous post is right, the extra cooling may not be worth the effort or the cost in the additional oil needed to maintain the proper oil level in the crankcase.

[jeff denton]

And don't forget, you don't want to cool the oil down TOO much, just a little is okay, oil doesn't like cycling way up and way down in temp.

[oldopelguy]

I'd say in normal driving with my very large truck, the only vehicle I have with an oil temp guage, the oil doesn't get within 20 degrees of the water temp except under extreme load and heat conditions. That said, it seldom gets warmed up anywhere near water coolant temps either.

While I doubt vry much you would gain a lot of benefit cooling-wise from running engine oil on an Opel through the rad cooler, you would gain a lot towards getting the oil warmed up to operating temperature quicker and with more stability when it's cold out. That cooler's about the same height as the oil pan, and really not that big (probably not 1.5 quarts), so it probably wouldn't affect oil level consideably, but It would be rather difficult to drain it when you try to change the oil. Probably the only way to drain it is with a remote oil filter kit, with the filter munted as low as you could so when the filter was removed everything drained. That brings up the fact that the initial start-up would have to fill all that mess before the bearings got any oil though, which would probably negate any benefit you got from the whole rig. I guess if you were running synthetic and changing oil once a year or so it might be worth doing the mod and pulling the dist annually to prime the motor, I'd have to think on it a it myself.

[GTJIM]

The heat exchanger in the bottom of the radiator is more of a trans fluid temperature stabilizer rather than an oil cooler. If you use an air-to-oil trans cooler it is a good idea to run the trans fluid back through the radiator coils to bring the trans fluid back to operating temperature.

With engine oil the temperature difference between coolant at the bottom of the radiator and the engine oil is too small to do much good at cooling. The differential in temperature between the water in the motor and the bottom of the radiator is maybe 50 degrees
With and air-to-oil cooler there is a greater temperature difference which makes it much more efficient - nearer 200 degrees difference in temperature ( air = 20 deg C Oil = 220/250 deg C)
Maybe the 'cooler' in the bottom of the radiator would be more likely to warm the oil most of the time - rather than cool it.

Cooling efficiency all depends upon the difference in temperature.

[ddoyle]

Another thing to keep in mind is the fittings on auto trans coolers are very small and I think would have an effect on the ammount of flow. Some auto makers do use an engine oil cooler in the radiator(chev trucks). These cooler fittings and their lines are about 1/2 inch in size. The aftermarket add on oil coolers are at least 3/8. Also may be some concern about the inside design, the auto trans coolers have very fine mesh type baffels, I would guess because the trans fluid is very light in viscosity. I think the best set-up for the opel would be a thermostaticly controled add on cooler and lines.

Dan