93 Chevrolet Suburban High Oil Pressure !!!

**Mercenary** · 09-27-2008, 02:51 PM

Hi Guys , im new to this forum and to the suburban trucks ! i just bought one , chevrolet suburban 1993 1500 , 350 5.7 L , the truck is now at 106 000 kilometers , and wondering , my oil pressure is real high when i start the truck ( the needles is at 400 ) have to wait 10 minutes for it goes at half of the gauge ( 200 ) ... if i run it at oil pressure at 400 , when i ask for big power the engine seem to wanna cut off !!! every info will be really appreciate , if someone have a idea !

**mehoff400** · 09-27-2008, 05:04 PM

always going to have high oil pressure when the engine is cold wait for it to warm up

**phoebeisis** · 09-28-2008, 10:47 AM

Mercenary, what are those pressure units? I'm certain they aren't PSI, but I can't remember "metric" pressure units(dynes per sq cm maybe?).

Normal pressure in PSI would be about 60 psi at start up, and maybe 25-40 psi at idle once fully warm. At 2000 rpms- once warm- mine 1998 (300,000 km 207,000 miles) runs about 45-50 psi.

Let us know the units, and we'll convert and see if they are normal.
Charlie

**mshuler009** · 10-04-2008, 10:44 AM

you're not over-full on oil are you....I've seen Jiffy Lube jobs where they've put 8 qts of oil in a 3.8 and it'll make it run weird.

**zippy** · 10-04-2008, 11:28 AM

Originally Posted by phoebeisis

Mercenary, what are those pressure units? I'm certain they aren't PSI, but I can't remember "metric" pressure units(dynes per sq cm maybe?).

Normal pressure in PSI would be about 60 psi at start up, and maybe 25-40 psi at idle once fully warm. At 2000 rpms- once warm- mine 1998 (300,000 km 207,000 miles) runs about 45-50 psi.

Let us know the units, and we'll convert and see if they are normal.
Charlie

Mercenary is from (French speaking) Canada, so his 'Burb instruments are metric. The units is question are kPa, kilopascals, his pressure of 200 to 400 kPa corresponds to 30 to 60 psi.

His truck's 106,000 kilometers is roughly 65,000 miles (like new).

Did you check out the pic of his 'Burb? I've not seen many with a work truck grill.

**29Roadster** · 10-05-2008, 12:13 PM

Those reading when converted to PSI sound fine to me. My 94 5.7 reads 60psi when cold, but after the engine warms up the pressure goes down to 35-40. I have the same reading from my other vehicles.

**unplugged** · 10-05-2008, 07:38 PM

Pressure seems OK. I would double check the oil level as previously mentioned. Stumbling when the pressure is high (aka cold) maybe some other temperature related issue. Check to see which thermostat you have. (and that it is operating properly) Should be a 195 F or 90 Celsius.