Oil Pressure - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


1992-1999 Series I L27 (1992-1994 SE,SLE, SSE) & Series II L36 (1995-1999 SE, SSE, SLE) and common problems for the Series I and II L67 (all supercharged models 92-99) Including Olds 88's, Olds LSS's and Buick Lesabres Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.

Reply
 
 
 
Thread Tools Search this Thread
Old 03-21-2005, 02:31 PM   #1
Senior Member
Posts like a 4 Banger
Thread Starter
 
Join Date: Oct 2002
Posts: 120
Thanks: 0
Thanked 0 Times in 0 Posts
crod101 is on a distinguished road
Default Oil Pressure

My '95 SSE (N/A) has 130K miles. I've had for 5 years now and since then I've been adding sytnthetic 10W40 Engine Oil. Recently, I've noticed when it'* in idle at a light that the Oil Pressure has been dropping below the safety range. Under normal driving the pressure is at 50-60PSI but at idle ti averages 20-30PSI. I know it'* not normal to drop below the safety margin. Is it the Oil Pump, Sender?
crod101 is offline   Reply With Quote
Old 03-21-2005, 02:40 PM   #2
Sol
Senior Member
True Car Nut
 
Join Date: Sep 2002
Posts: 8,909
Thanks: 0
Thanked 0 Times in 0 Posts
Sol is on a distinguished road
Default

My 95 used to do that. I think it was the sender that was just screwy.
Sol is offline   Reply With Quote
Old 03-21-2005, 02:48 PM   #3
Junior Member
 
Join Date: Mar 2003
Location: Purgatory
Posts: 0
Thanks: 0
Thanked 0 Times in 0 Posts
vital49 is on a distinguished road
Default

What you're experiencing is not uncommon. Sounds like the sender is fine if it'* actually moving up and down with the engine RPMs.
vital49 is offline   Reply With Quote
Old 03-21-2005, 02:58 PM   #4
Senior Member
Posts like a Supercharger
 
Join Date: Dec 2003
Location: Menomonee Falls, WI
Posts: 158
Thanks: 0
Thanked 0 Times in 0 Posts
neekolas is on a distinguished road
Default

why are you using 10W-40 isnt that a little heavy????? Im just asking that for intrest, a heavier oil would actiually increase your oil pressure...... do you ever get lefter noise form usng a heavier oil on startup?

nicky
neekolas is offline   Reply With Quote
Old 03-21-2005, 03:02 PM   #5
Senior Member
True Car Nut
 
Join Date: Mar 2004
Location: Ames, Iowa
Posts: 3,066
Thanks: 0
Thanked 1 Time in 1 Post
bill buttermore is on a distinguished road
Default

Oil pressure is pretty responsive to temperature. Check the temperature the next time the pressure is low. With idle speed low and temperature high, oil pressure usually will fall in all but the tightest engines. As your bearings wear and develop clearance, you may want to consider a higher viscosity oil like 15W-40. I like Shell Rotella T.

I had an old Mercedes Benz repair manual that said you were OK as long as the engine developed 7 pounds of pressure for each 1000 rpm. But, I must say, I would be very worried to see my pressure drop to 10 psi or less at idle!
bill buttermore is offline   Reply With Quote
Old 03-21-2005, 03:26 PM   #6
Senior Member
Posts like a 4 Banger
Thread Starter
 
Join Date: Oct 2002
Posts: 120
Thanks: 0
Thanked 0 Times in 0 Posts
crod101 is on a distinguished road
Default

I've actually been putting 10W-30 in the winter and 10W-40 in the summer. I'll have my mechanic look at the Sender and look into using 15W-40.
crod101 is offline   Reply With Quote
Old 03-21-2005, 04:03 PM   #7
Senior Member
True Car Nut
 
Join Date: Jun 2002
Location: Bedroom, Ontario
Posts: 3,266
Thanks: 0
Thanked 0 Times in 0 Posts
Drifter420 is on a distinguished road
Default

err.. the 30 and 40 is viscocity @ operating temp ( well past warm ups ).

The only thing I can think as stated as to why you would run 40'* is bearing and piston seal issues ( gettin a lot of blow by ).

15W-40 would only be thicker during start up compared to 10w-40 ( not including brands base stock and oil additive used. )

Well.. as far as I know any oil pressure between 20-100 psi I wouldn't worry about.

I'm running close to 80 PSI on throttle and during warm ups and around 60 PSI on Idle after 25 miles or so during idle.
I'm using Esso XD-3 0w-30.. I've tried different brands of oil and grade and they're relatively the same reading according to the gauge.. and as far as I know.. those gauges are never accurate for any car
Drifter420 is offline   Reply With Quote
Old 03-21-2005, 05:51 PM   #8
Senior Member
True Car Nut
 
Join Date: Mar 2004
Location: Ames, Iowa
Posts: 3,066
Thanks: 0
Thanked 1 Time in 1 Post
bill buttermore is on a distinguished road
Default

Quote:
Originally Posted by Drifter420
err.. the 30 and 40 is viscocity @ operating temp ( well past warm ups ).

The only thing I can think as stated as to why you would run 40'* is bearing and piston seal issues ( gettin a lot of blow by ).

15W-40 would only be thicker during start up compared to 10w-40 ( not including brands base stock and oil additive used. )
I gotta read more carefully before I speak. Thanks for correcting me, Drifter.
bill buttermore is offline   Reply With Quote
Old 03-21-2005, 07:34 PM   #9
Senior Member
True Car Nut
 
Join Date: Jun 2002
Location: Bedroom, Ontario
Posts: 3,266
Thanks: 0
Thanked 0 Times in 0 Posts
Drifter420 is on a distinguished road
Default

Quote:
Originally Posted by bill buttermore
Quote:
Originally Posted by Drifter420
err.. the 30 and 40 is viscocity @ operating temp ( well past warm ups ).

The only thing I can think as stated as to why you would run 40'* is bearing and piston seal issues ( gettin a lot of blow by ).

15W-40 would only be thicker during start up compared to 10w-40 ( not including brands base stock and oil additive used. )
I gotta read more carefully before I speak. Thanks for correcting me, Drifter.


no prob.. everyone has their typo days.. me included

But it takes a bigger and more mature man to admit to it..
Drifter420 is offline   Reply With Quote
Old 03-22-2005, 10:14 AM   #10
Senior Member
Posts like a 4 Banger
Thread Starter
 
Join Date: Oct 2002
Posts: 120
Thanks: 0
Thanked 0 Times in 0 Posts
crod101 is on a distinguished road
Default

My mechanic is going to replace the sender unit and if that doesn't work the oil pump. Where'* the Sender Unit? Is it difficult or expensive to replace? What about the oil pump? I've heard it could be internal, difficult to replace and expensive. Is this true?
crod101 is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
SC oil and oil pressure jnoetzelmann 2000-2005 2 03-24-2010 12:19 AM
very high oil pressure reading after oil change txmike 1992-1999 3 01-10-2010 11:41 PM
1995 SE--burning oil, low oil pressure gauge. AeroCoupeSS87 1992-1999 2 12-10-2007 09:52 PM
Low oil pressure. Thicker oil? J Wikoff 1992-1999 71 06-08-2006 11:54 AM
Low oil pressure sensor in oil pan... Bob Dillon 1992-1999 9 05-11-2006 09:23 AM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 02:35 PM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.