OK, So I have noticed that in the heat of texas when my engine comes to operating temp my oil pressure drops. (More than it did when it was cooler outside) Theres no leaks, runs excellent so I guess it is because the oil starts to become thin or breakdown because of the heat. I thought of putting a oil cooler on my stock 2.8 to help this out, and extend the life of my oil and engine. Is this a good Idea? Would putting an oil cooler on hurt my engine, or cause it to run badly? Iam lucky to have a good engine, I dont want to ruin it by putting this on here. I tryed search, couldnt quite find my answer. Thanks

Zach

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CArz I own:
'85 Fiero GT
'86 Monte Carlo SS
'87 Fiero GT

"Speed has never killed anyone, suddenly becoming stationary... That's what gets you." - Jeremy Clarkson

"Fear disturbs your concentration." - Sabine Schmitz

An oil cooler will not hurt anything. It may help keep the oil a little cooler. It will not fix your problem though. Depending on how low the preasure drops, it may not even be a problem.

Iam pretty sure that is the problem. When it gets to operating temps, when its not 105 degress outside, its runs a steady oil pressure of 60-65 psi. I will be honest and say Iam not sure of the PSI that it drops to, but when its 105 out and Iam sitting in traffic, engine running at temp or hotter, it begins to hover around the middle of the gauge. (whats that 45-50 psi?) I guess I should add that Iam running synthetic oil, and the recommended weight. I cant say that I am losing oil, no leaks anywhere, and I always check the level, it stays the same. So cooler oil wont help this problem? I thought I read somewhere that would help.

The drop in pressure on the gauge is pretty normal for the 2.8. Of course when it gets hotter outside, this shows up alittle more than when its cooler. I wouldnt worry with it to much but it is always an option. If you do add a oil cooler to the motor, just remember that is one more thing that can cause issues.

40+ PSI is still great. I kind of douby an oil cooler is going to do too much anyway, it wont do anything at idle.

5w30 in the winter flows much slower out of the bottle, in the summer its almost like water. coolant cant really cool the oil very well without a more direct form of contact such as a coolant/oil cooler found in german cars. getting a thermostatic oil cooler is a good idea period since all oil is designed around a 180 degree operating temperature where it lubricates and cools best(also the oil filters work best at that temp). getting an oil cooler is a good idea but make sure its got the internal valve to regulate flow through the cooler also buying the more expensive kits assures you the line pressure wont blow out the cooler lines and make a huge mess. it also lets you run the full 240deg. temp thermostat/fan switches because the motor temp is better regulated and you dont have to run cooler thermostats to bandaid the problem.

to see higher pressures in the winter and lower pressures in the summer is common in all cars, just be glad you dont have an aircooled motor

Well, Reading all of your comments (Thanks) I will think about it a little bit more and if I think I want it, I might put it there. I didnt know that a drop in pressure was common along 2.8 or any engine for that matter. My 86 Monte ever had that issue. MstangsBware, you have a point. Thats is just one more thing to cause issues. I also thought about putting one in because Iam about to purchase side scoops and I would have liked them to be functional in some way. Anybody else have any comments, anybody have one installed, what you think?

Why not just change to a higher weight oil? Say 10w 30 or 20w 50? it will not hurt anything in hot weather.

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quote Originally posted by DCRFiero1: Anybody else have any comments, anybody have one installed, what you think?

Oil pressure drop over time with engine running is pretty typical for all engines and it has a lot to do with the temperature. When the coolant temp gauge failed on my first 2.8L, the oil pressure gauge warned me of creeping engine temps due to a cooling fan problem, when the oil pressure gauge started to read much lower pressure than what it normally did under the conditions at that time.

The hotter the oil particularly above normal, the greater the risk of bearing failure. When test driving a GT I had let sit for months, the radiator developed a severe clog from corrosion. The inlet tank exploded within 5 minutes of driving. It didn't harm the head gaskets during the overheat but it destroyed the crank mains, the radiator blockage hid the true engine temps until the tank exploded and I never thought to look at the oil pressure gauge so early in the test drive. The rods were okay but the crank journals had grooves about .050 deep and 2/16 wide.

I have run a thermostatically controlled unit before which worked well however, in the Fiero it needs to be in a wind stream to work properly, I have a 400 hp rated cooler now with direct continuous flow in the back of the car and my oil temps are still climbing to about 240 deg despite the additional OE coolant cooled oil cooler the oil filter is attached to. Some of the heat is from the turbos and some from the oil squirted on the bottom of the pistons. I plan to move the cooler to the front of the car the way Porche did with some of their earlier cars.

The only drawback I see with Firefighters idea of using a thicker oil is the effect on fuel economy. A major part of the reason cars are rated mostly for 5W 30 is because some years back the Govt. forced auto manufactures to sell their cars with the exact same specs they tested cars under to obtain their fuel economy etc. claims because the general public was having trouble duplicating them. Some of you remember the big fall out that occured when either chevy or buick/olds owners discovered they had mis matched engines in their cars from the factory not sure if it was olds in the chevy or visa-versa.

You shouldn't have a problem regardless of what you decide as long as your pressure is good. You can always improve on it though.