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I miss you little guy
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1,546 Posts
Discussion Starter #1
I just got the car back after a year. I remember it running around 30-35 pounds at idle and 40-45 when cruising and under acceleration. Before my dad drove it down to Florida for me he had the oil changed and they put 10-40 in it. Now the most pressure it sees is 30 pounds. This being an older car should I just keep the heavier oil in it or switch it back to 5-30?

This is for my '90 firebird with the 5.0
 

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My Dixie Wrecked
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5,510 Posts
Since my oil pressure is kinda blah, I run 10w30 or 10w40.
I sometimes run 5w30, but very seldom as its too thin and my truck burns oil
 

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AllOffTopic.com FTW!
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8,460 Posts
The oil pump and all the little passages are designed for the specified oil...it might be worth running what's specified.
 

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I miss you little guy
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Discussion Starter #4
That's kind of what I was thinking, thinner oil pumps easier.
 

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I miss you little guy
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1,546 Posts
Discussion Starter #6
Somebody else suggested that to me also. I might go that route. Does it matter that I'm about to make a 3k mile drive?
 

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I miss you little guy
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Discussion Starter #11
I'll be more specific, it runs like you drove it brand new off the lot, the body is in excellent shape, the transmission shifts nice and firm and it has under 80k miles.
 

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I miss you little guy
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1,546 Posts
Discussion Starter #12
Ok, here's what I'm talking about. I seafoamed the car, changed the oil back to 5w30 and added a can of engine restore. This was a few hours later.

th_VCLP0189.jpg
 

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HOT AIR BALLOON OWNER
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14,932 Posts
You're going off a stock gauge? lol

Just put some oil in it and drive on.
 

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I miss you little guy
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Discussion Starter #14
Well, the stock gauge used to read a lot higher. So I'm just a little concerned.
 

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HOT AIR BALLOON OWNER
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Maybe it's just getting out of range as it's 20 years old. Also you have different weight in there, could be different brand, could be seasonal too.

You have oil pressure, just drive.
 

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I miss you little guy
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1,546 Posts
Discussion Starter #16
It's a new sending unit. I put 5w30 in it because that's what is supposed to be in it, it had 10w40 in it before.

Could a WOT run hurt anything? it used to be around 45-50 at WOT, now it just hits 30.
 

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HOT AIR BALLOON OWNER
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14,932 Posts
It's a new sending unit. I put 5w30 in it because that's what is supposed to be in it, it had 10w40 in it before.


There you go, could be manuf tolerances between sending units.
 

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I miss you little guy
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1,546 Posts
Discussion Starter #18
I edited that post to, got an answer for that question too?
 

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HOT AIR BALLOON OWNER
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To me, it's still dealing with the inaccuracy of the OE gauges. For example, the oil pressure gauge in my F150 reads dead center (says NORMAL) even down at 7psi...

Get a mechanical gauge for more exact readings. $40 and you can get an Autometer which are decently accurate.

If you had low/no oil pressure the top end would be real noisy.

I do not see a WOT run causing any issues (aside from being comically slow and wasting fuel :jester:) as you still have oil pressure. I don't have a clue what style of pump is in there and what the max pressure it allows.



 

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I miss you little guy
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1,546 Posts
Discussion Starter #20
TBI 305 isn't my fault. That can be changed, it isn't THAT bad though:rofl2:

The light weight helps a little. The 2.73's dont. Thanks for the help dok.
 
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