: Engine oil cooler question

05-08-07, 01:00 AM
My friend has a 97 STS. It does not have an air-to-oil cooler right side and in front of the radiator. Another has a 96 ETC with an air-to-oil cooler right side and in front of the radiator. I have a 95 FSM and it seems that any N* equipped, 95 cars come with an air-to-oil cooler in front of the engine. All of them come with water cooled oil cooler in the radiator (in the right side radiator tank).

So, is this air-to-oil cooler an option, year dependent thing, or what? Does anybody know about this cooler? Also, if this is up to 96 thing, what made GM to eliminate this after 97 model year? Change in oil spec.? I don't think cooling capability between pre-96 and 97 and up is different.

Thank you!

05-08-07, 07:03 AM
My '97 SLS had a power steering air-to-oil cooler on the passenger side, down low, in front of the A/C condenser. Maybe this is what you're seeing on the '96 ETC? The '97 STS should have it I would think.

05-08-07, 02:00 PM
Thank you for your reply, jadcock.

Yes, you are right that there is another cooler on the left side of the radiator and that is the power steering oil cooler. However, what I am talking about is different. It is located on the RIGHT side of the radiator and much bigger. I think I have a photo showing that cooler (on the 96 ETC) that I can post here later.

05-09-07, 12:12 AM
This is the oil cooler I have been talking about.

Thank you.

PS: this is my first time to attach picture, so I am not sure if it comes fine or not...

05-09-07, 12:58 AM
Thank you for posting topic and especially the pix of cooler.

I am interested in learning more about oil cooling in the N* engine.

After viewing your cooler PIX two questions arise 1. Can you check the BUILD tag factory and see if TOW package is mentioned? 2. The fluid lines attached to cooler are big diameter, can you trace them back to point of attachment?

N* has 7.5 qt oil capacity which I originally thought was very generous so why would it ever need an Oil/Air cooler?


05-09-07, 01:33 AM
Keep in mind that 100 is posting a picture of a 4.9, not a Northstar, if that makes any difference.

05-09-07, 07:09 AM
I think 100 said that photo was from a '96 ETC.

C170B, you are right -- the large sump does negate the cooling need a bit. It's also a factor in allowing for our longer OCIs (Oil Change Intervals).

05-09-07, 10:08 AM
So he did. I stand corrected.

05-09-07, 10:51 AM
Looks like an aftermarket addition to me.

05-09-07, 01:05 PM
Ranger, sorry for the confusion, but you are right, I don't have it. It is on my friend's (well, not exactly) Eldorado with N* in it.

My friend who has a 97 STS went to one of Cadillac meeting thing and he has a chance to see that 96 Eldorado. He found one cooler (that is the cooler in the photo I posted above) that his STS doesn't have. He asked me about this cooler. I checked my FSM (that is for 95 cars) and found one (see attached figure). I also went to GMpartsdirect.com website and found one as GM genuine part (I mean it has a GM part number). I thought this is a simple question...

But it seems like no one has one (based on how this thread is going), except that 96 Eldorado in the photo. I will see if I can get RPO of that 96 Eldorado. I suppose it must be a rare option or something...

By the way, C170B, my 95 SDV came with a towing package and it has an ATF-to-air cooler on the left side of the radiator above the power steering fluid cooler. But it does not come with this oil-to-air cooler.

Thank you.

05-09-07, 06:40 PM
To my knowledge Cadillac discontinued the oil cooler in 98 party because oil quality has improved over time and the oil temps weren't that much higher with the cooler removed. I just did a 99 engine swap to my 96 and I replaced the oil cooler adapter with the non-cooled 99 unit. My 96 STS has the towing package but I dont tow nothing around. If for some reason the temps do go up I am going to have to buy some new aftermarket lines and reconnect it. As far as that second cooler, I also saw it in my 96 FSM, I guess it must be an additional cooler, why- beats me.

05-09-07, 10:51 PM
So, the '99 oil filter adapter does not have the oil cooler lines?

05-11-07, 07:34 PM
So, the '99 oil filter adapter does not have the oil cooler lines?

My 99 did NOT come with an oil cooler, however I have read a few other threads here and some people said that their 99 was fitted with an oil adapter. But when I looked around for radiators for a 99 on the internet ALL of them were WITHOUT the oil fitting adpaters on it, but only came with the trans ones. I am going to ask the dealer if the tow option was used in 99 and/or if they were oil cooled.