Oil Change Interval?

Reply Subscribe

Thread Tools

Search this Thread

Mar 17, 2007 | 07:34 PM

#31

asavage

FTE Community Team

Joined: Nov 2001

Posts: 1,870

Likes: 276

From: Oak Harbor, Washington

Folks, the oil debate was over two years ago. I just tagged on the oil pressure "sender" pic because I found it while cleaning up and before throwing it out I thought I'd post it, and because I'd first mentioned it at the end of that old thread, I put the pic there.

Let's not rehash the OCI, it's all been said before.

Mar 18, 2007 | 08:40 AM

#32

LTCPipkin

Junior User

Joined: Jun 2006

Posts: 99

Likes: 0

From: Newmwnstown, PA

Low Oil Pressure

Quote:

Originally Posted by occupant

I don't have any oil change history on my '91 3.0L, but I bought it with 145K on it, changed the oil at 151250, 163880, and I might get around to it again soon. Looking at 168000 as of this morning. Maybe I'll go to 175000 and change it again. Oh, and I have low oil pressure, too. Lots of pressure when cold. But once warmed up it stays between the N of NORMAL and the red zone. I'll wait to hear knocking before I try to figure that one out.

I had the same problem a few weeks back and began planning to evaluate a new oil pump, or just rebuild the engine. I decided to take the "bad sending unit or gage" approach change those out first. I started with the sending unit and discovered the plug was covered with oil and dirt. I probably could have just cleaned the plug and connector to the existing sending unit. But I decided since I already had the cover off in the passenger compartment and a new sending unit in my hand, and with 201K miles on the old one, I'd just change the thing anyway. I now get good oil pressure --between O & R of NORMAL, mostly towards "R".

Prepare to lose some knuckle meat and possibly bleed a little. The oil pressure sending unit is in a tight spot (top right rear of engine on passenger side, just below the distributor) and several sharp parts nearby. Also, don't confuse this oil pressure sending unit with the "low oil level sending unit" mounted in the oil pan on thie side. This one lights up the "Low Oil" light, not the analog or digital oil pressure gage.

Recommend you also consider changing the distributor cap and rotor while you are back there. It might even give you a little more room to work with the oil pressure sending unit if you remove the distributor first.

Good luck,
Michael
'93 Aero 3.0L
'94 Aero 4.0L

Mar 19, 2007 | 12:26 AM

#33

Bear River

Former ******

Joined: Nov 2004

Posts: 4,901

Likes: 2

From: Salt Lake City, Utah

Changing you oil at 3,000 miles is for severe duty. The conditions that qualify as severe duty are outlined in your owners manual. 7,500 is good for all other uses, assuming the engine was properly broken in to ensure the oil is not getting contaminated with blowby.

Mar 19, 2007 | 09:50 PM

#34

xlt4wd90

Lead Driver

Joined: Sep 2003

Posts: 7,018

Likes: 210

From: SoCal

Michael,

Which engine was that? I think on my 4.0L, the oil pressure switch is on the front left side of the enigne, behind the power steering pump. It would require removal of the AC compressor and PS pump to get at.