No fittings on my radiator for trans cooler lines???

[Kfort]

I'm converting my C20 from a manual Saginaw 3-spd to a 700r4. I don't see fittings on my stock 4 core radiator to run my tranny's cooler lines. Am I not seeing something? Can I modify my existing radiator or should I buy a new radiator with the fittings? My stock radiator works great with no leaks so I hesitate to buy a new if I can modify what I've got. It's not the price but seems like every time I buy a new part, it just never seems to fit/perform quite as well as factory. Whatcha' think?
Many thanks in advance. Advice from "The Forum" is always priceless.
*****I've added a Derale external transmission cooler 13"x13.5"x2" mounted in front and a temp gauge to monitor tranny temps but it's just not quite enough.

[Overdriven]

The trans cooler built into a radiator is just a loop of line in one of the end tanks. If there are no fittings on the end tank there’s no loop inside. A competent radiator shop should be able to add one, but it would require removing the end tank, adding the cooler and putting the end tank back on. It’s either that or buy a new radiator, I’m not sure which would be less expensive you’d have to get quotes.

Not sure about our trucks but many vehicles with a manual transmission didn’t have the trans cooler in the radiator. It saves money and provides one less point of failure so why put it in the radiator if the vehicle doesn’t need it.

[MARKDTN]

I would buy a new one with fittings. If you want to re-use your old somewhat, you could get a new core installed between your old tanks and have the cooler added at that time while it was apart.

[Minkota]

another option would be to buy an external Transmission Cooler that mounts in front of the Radiator. i think these are more efficient at keeping the Transmission temp down as well.

[54blackhornet]

Pretty simple to just install a transmission cooler by itself. No reason to touch your radiator.

[Kfort]

I have the largest external trans cooler that will fit in place but it's not enough.

[Minkota]

Originally Posted by Kfort

I have the largest external trans cooler that will fit in place but it's not enough.

what RPM are you running when at highway speed? what temp is it showing the trans is running at?

It has been my experience that the trans Coolers built into the radiator keep the fluid at a higher temp as they are surrounded on all sides by the hot engine coolant. I have always had better luck with external coolers; once I had to use 2 coolers plumbed in series.

Just to confirm, you have the Cooler place on the front side of the radiator, correct? I only ask because I have seen it mounted on the backside where is does very little due to hot air coming off the radiator....

[Kfort]

I dont have a tach but my new 700r4 has dropped the RPM's down significantly @ highway speed. The external cooler is mounted out front in front of the condenser. I took it for a test run on the highway with a 3,000lb cabover camper. Temp gauge topped out @ about 255/260 pulling a moderate incline. While running on flat grade with camper, temp hovers around 200. I want to do some cross country driving with camper so I would like to be prepared for some REAL inclines.

[Minkota]

Have you tried using any of the Synthetic High Temp ATF products in place of traditional ATF?

[Kfort]

I have not. I'm worried about doing damage to 700r4.

[special-K]

You have a radiator for manual transmission. You need a radiator for automatic transmission.

[Minkota]

If you do switch to a “Automatic” radiator with a built in trans cooler, I would still use the external cooler and plumb it in series, the longer it has in the cooler the lower the temp and there will be more volume of fluid.

[Kfort]

Thanks for all the input, it was great. I'm going to do what you've suggested and #1 Install a new 4 core automatic transmission radiator
#2 Plumb in series with an external cooler (13"x13.5"x2")