Oil cooler delete = better MPG?

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I discovered a slight leak coming from the oil cooler lines from my '99 Crown Vic PI. The lines will be cheap and easy to replace, but at the same time I learned that the oil cooler assembly can be deleted entirely.

Though this would require more work, I wondered if eliminating the oil cooler would cause the car to warm up faster, and thus result in better MPG? I use the car primarily for relatively short trips, and the engine usually gets up to operating temperature, but I thought that deleting the oil cooler would get it up to operating temperature faster, and thus result in better MPG.

I know that there is a transmission cooler on this model as well, I do not know if it can be deleted, but if so, would this also get transmission fluid to operating temperature faster and also result in improved MPG?

Please note that I have the 4.6 modular engine and I never intend to tow anything with this vehicle, and the vehicle will not see extensive idling in hot conditions.
 
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I highly, highly, highly doubt that it would improve fuel economy even a noticeable amount. Never, ever, ever entertain the thought of getting rid of the tranny cooler. The transmission will be a big lump of so much steel and aluminum before you can say hunky dory.
 
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It would probably result in lower MPG. The coolant warms up BEFORE the oil and the oil-to-coolant cooler on your Vic will cause your oil to heat up sooner with coolant heat.

Do a search on Gary Allan's posts and you'll find some test results he did with his Jeep Wrangler's heat exchangers a few years back. Basically he found that the coolant heats up to full temp in a couple minutes whereas the oil doesn't reach the same temp for 10-20 minutes under a highway driving scenario.

If you're concerned about the price I would check out junk yards and Ebay motors (http:\\motors.ebay.com). Ebay is the place where I learned about your Crown Vic heat exchanger a few years ago.
 
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you're in southern Louisiana, how long could it really take to warm up anyway? 10 seconds???
you're driving a big RWD V8 sedan, there's only so much mpg you can expect.
 
Originally Posted By: Eddie
Fix the leaking lines and run as intended.


x2.

A lot of people install oil coolers, why disable what you have?
 
The oil heat exchanger is not only for emissions but keeps the oil at the optimal temperature for a less wearing engine and longer oil life.
 
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Is the external oil cooler controlled with a thermostat? If so I'd leave it alone, I don't think you can improve on that. If its not you might try just blocking the air flow and see what that does, realistically any mileage gain is probably going to be low, like 0 to 3%.
 
Generally you don't want to delete a cooler unless you have specific reason. Coolers only do a differential of temperature between the fluid temp and the ambient (outside) temp. So, when the oil is cool, very little cooling is done. When the oil is hot, lots of cooling gets done because the difference in temperature is much greater and the cooler can use it's entire effective temperature differential. If for no other reason than that, deleting coolers is generally not recommended.
 
I don't see how it would help with fuel economy. The transmission will warm up alittle quicker that's it. In the winter it may help but in the summer you'll toast that puppy. A good test would be is too install a temp gauge. Get a reading with the cooler during winter driving. Then put a piece of card board in front of the cooler and compare readings. If there is a big difference in readings imagine what those readings would be in the summer.
 
Ah, some very solid answers about the oil cooler. I don't know a heck of a lot about engine design, so these answers are very enlightening.

Ford sells an oil cooler delete kit, mainly geared for people whose oil coolers have failed and don't want to pay for complete replacement (which runs I think nearly 350 for the part and a couple hours mechanic time).

Since my Crown Vic doesn't and will not see anywhere near the abuse that it is designed for, I thought perhaps shedding the oil cooler might be an MPG tweak that would make sense. I guess not; so, it just a couple new hoses to fix the leak and leave it be.

Thanks again for the quick and knowledgeable replies.
 
I'd leave in the cooler because you don't know what unintended side effects could result.

But just for the sake of discussion (hypothetically), I'd say it would probably increase MPG by a very very small amount (too low measure). The reason is less hp used by the oil pump. The more plumbing that fluid flows through, the more power is needed to pump the fluid.
 
Originally Posted By: daves66nova
I'd fix the leak,leave the cooler on, and cover the cooler with something,so that it doesn't cool the oil.


There is nothing to cover. It is a tube that engine coolant flows through, and engine oil flows around. It is just a fluid to fluid heat exchanger, and it works in both directions (a VERY good thing!). It is more of a temperature stabilizer than a cooler. It is a big part of why using a 5w-20 is perfectly acceptable in these engines, even when driven hard.

This is what they look like http://www.supermotors.net/getfile/749429/fullsize/pi-oil-cooler.jpg
 
Many here missed the point entirely.

He's talking about a Police Interceptor model with a factory engine oil cooler. Not the trans cooler!

Chuck, you can remove/delete it at will, and the car may never notice!
 
Thank you for noting that the transmission cooler delete suggestion was merely incidental to the question about the oil cooler delete, SeveSRT8. I didn't want to be rude.

Since it has already been stated that the coolant will actually help to warm up the cool oil, it seems obvious to me that no gains in MPG would be noted, and in fact a slight loss might even be detected. So I will just replace the leaky lines and leave it at that.
 
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