transmission/oil cooler lines

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Ryanbrown36

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Hey guys, Im finishing up a Oldsmobile 5.7 diesel to Sbc swap and noticed my transmission cooler has 4 ports. I'm hoping to start it up this week in hopes of getting it on the road for a bit before winter and want to know what I should do with it. I'm not very knowledgeable about this stuff and learning as I go here so might be a dumb question. I'm just trying to get it started as soon as possible and don't want to spend money in the wrong places. from what I've read I can buy a new trans cooler with two ports, run a oil cooler or was hoping I could maybe plug those two holes. thanks in advance
 

Ricko1966

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Is this a factory cooler? Possibly a water to oil heat exchanger? If so you'll want to run heater hoses through 2 ports transmission lines through the other 2. I personally would use a radiator with the built in transmission cooler and if I was going to run an external cooler I'd run transmission pressure line to external cooler,external cooler to radiator cooler,back to transmission. That way the radiator regulates transmission oil temperature so the ATF is not too cold
 
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Ryanbrown36

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Oscar this a factory cooler? Possibly a water to oil heat exchanger? Of so you'll want to run heater hoses through 2 ports transmission lines through the other 2. I personally would use a radiator with the built in transmission cooler and if I was going to run an external cooler I'd run transmission pressure line to external cooler,external cooler to radiator cooler,back to transmission. That way the radiator regulates transmission oil temperature so the ATF is not too cold
I am not sure if it is a factory cooler but if I had to guess I would say yes, I believe the two extra ports used to run to an oil cooler at the oil filter. I would prefer to not have to buy a new radiator if possible. My heater core lines currently run through the rad if that helps and all ports on the trans cooler fit a 3/8 hose.
 

Ricko1966

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I am not sure if it is a factory cooler but if I had to guess I would say yes, I believe the two extra ports used to run to an oil cooler at the oil filter. I would prefer to not have to buy a new radiator if possible. My heater core lines currently run through the rad if that helps and all ports on the trans cooler fit a 3/8 hose.
If you have a radiator with 2 ports for transmission cooler,just run lines from the transmissiin to the radiator an forget about.
 

Ricko1966

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Pics. Hard to tell what you have with out pics.
 

Matt69olds

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What year is your truck? I don’t recall any heat exchanger on my 81 GMC, but it’s been 30 years since I swapped in the 455. I have slept a lot since then.

I’d suggest using a radiator with a trans cooler built into it, or using a stand alone cooler.

Either way, don’t scrap the factory olds engine frame mounts. There are people who will buy them.
 

Ryanbrown36

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What year is your truck? I don’t recall any heat exchanger on my 81 GMC, but it’s been 30 years since I swapped in the 455. I have slept a lot since then.

I’d suggest using a radiator with a trans cooler built into it, or using a stand alone cooler.

Either way, don’t scrap the factory olds engine frame mounts. There are people who will buy them.
The truck is a 81, I think I forgot to mention that it has a stand alone cooler (that has 4 ports). Yes I did end up keeping the mounts as someone offered me $100 for them, is that a alright price for them?
 

Matt69olds

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I’m not sure what a fair price is, never had a pair to sell. Since im an Olds guy occasionally people ask if I know or have frame mounts for sale. The only pair I have are on my truck.

I can’t think of any reason to keep the existing cooler. Either use a radiator or a stand alone cooler. Least amount of questions going that route.
 

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