Notices
1948 - 1956 F1, F100 & Larger F-Series Trucks Discuss the Fat Fendered and Classic Ford Trucks

Oil pressure

Thread Tools
 
Search this Thread
 
Old Jul 10, 2005 | 10:47 PM
  #1  
black58's Avatar
black58
Thread Starter
|
Elder User
Joined: Nov 2003
Posts: 576
Likes: 9
From: Rockford, IL
Oil pressure

Hi guys, I've got a 58 F100, '73 302/c4 combo. At operating temp, oil pressure drops down considerably. Two questions. What is the ideal running pressure for this engine? I've tried a lower temp thermostat ( to lower operating temp) and thicker oil. I had the same problem on the stock 223. I replaced the oil pump with a stocker and nothing seemed to happen. The pressure still dropped when the oil got hot. I havn't tried synthetic oil yet but I don't believe that it would solve anything. I've heard that a high volume oil pump will just suck the pan dry. I was also told I should rebuild the heads if I try to use the HV oil pump. Would an oil cooler take care of this? That brings me to the second question, anyone have any other suggestions? I've been told that maybe the lifter bores or the lifters themselves may be worn, allowing oil to run past them consequently dropping the oil pressure. Any one want to second this notion? So, low oil pressure is bad but how low is low. I have an oil gauge with just the low/high setup. When the engine starts the needle hits just above the middle. After warmup, the needle is just above the warning spot on the gauge. I can put a suitable numbered gauge on but I would like to know what numbers I'm looking for. Well, thanks for letting me ramble, I sure like this site. John
 

Last edited by black58; Jul 10, 2005 at 10:51 PM.
Reply
Old Jul 10, 2005 | 11:02 PM
  #2  
Goobzilla's Avatar
Goobzilla
Elder User
Joined: Jul 2002
Posts: 520
Likes: 0
From: Wellington, CO
Get a good mechanical oil pressure gauge. I always use the 10 psi per 1000 RPM rule.
 
Reply
Old Jul 11, 2005 | 04:59 PM
  #3  
Jag Red 54's Avatar
Jag Red 54
Logistics Pro
20 Year Member
Joined: Oct 2002
Posts: 4,489
Likes: 5
From: Valley Center, CA
My 289 idles at about 35-40 psi. You said that you tried heavier oil: what weight 40? 50? Do the cheap stuff first. How about a can of STP? I have also heard that a high volume oil pump will help. It will not suck the pan dry. Good luck, Jag
 
Reply
Old Jul 11, 2005 | 05:37 PM
  #4  
texan2004's Avatar
texan2004
Cargo Master
Joined: Nov 2004
Posts: 2,858
Likes: 3
From: Friendswood, Texas
Step one, get a good mechanical gauge to verify that you really have a problem. If you do have a problem, my guess would be that your main bearings are beginning to go. Low oil pressure once the engine is warmed up is a classic sign of this.

On the upside, I've always been able to run them for almost an eternity this way but this was never in a vehicle that I was too worried about or that I had much invested in. Usualy an old beater car or truck.
 
Reply
Old Jul 11, 2005 | 05:52 PM
  #5  
pootscratch89's Avatar
pootscratch89
Senior User
Joined: Apr 2005
Posts: 207
Likes: 0
From: Burkburnett, Texas
What weight of oil are you using? A straight weight oil (ie. 30W) instead of 10W-30 might help also. I definitely agree with the others though; get a numbered guage; they're fairly cheap, and see what pressure you are actually running.
 
Reply
Old Jul 12, 2005 | 05:51 AM
  #6  
GreatNorthWoods's Avatar
GreatNorthWoods
Lead Driver
20 Year Member
Photogenic
Photoriffic
Shutterbug
Joined: Apr 2002
Posts: 8,813
Likes: 13
From: Littleton, New Hampshire
I agree with Texan especially if this is a high mileage engine. It is time for a lower end rebuild. Anything else is just a bandaid...

Vern
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
wjjarvis84
6.0L Power Stroke Diesel
5
Sep 14, 2012 05:50 PM
JBronco
1978 - 1996 Big Bronco
9
Nov 8, 2011 11:59 AM
zachsherman88
335 Series- 5.8/351M, 6.6/400, 351 Cleveland
3
Feb 22, 2009 02:40 PM
jimsville
Big Block V8 - 385 Series (6.1/370, 7.0/429, 7.5/460)
15
Sep 26, 2006 09:53 PM
gadams
1967 - 1972 F-100 & Larger F-Series Trucks
6
Apr 10, 2002 05:31 PM




All times are GMT -5. The time now is 06:19 AM.

story-0
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level

Slideshow: The VelociRaptor Expedition gains a lift, upgraded suspension, Brembo brakes, and trail-ready equipment while retaining the stock 440-horsepower EcoBoost V6.

By Verdad Gallardo | 2026-06-12 11:01:55


VIEW MORE
story-1
Top 10 Fords at 2026 Carlisle Ford Nationals

Slideshow: Top 10 Fords at 2026 Ford Nationals

By Joe Kucinski | 2026-06-09 11:10:08


VIEW MORE
story-2
3 Best / 3 Worst Parts of Modern Ford Ownership

Based on years of owning multiple modern Ford products.

By Brett Foote | 2026-06-09 10:53:36


VIEW MORE
story-3
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches

SPONSORED: From muddy boots to rain-soaked cargo, these upgrades address some of the most common frustrations Ford truck owners face every day.

By Pouria Savadkouei | 2026-06-08 18:50:34


VIEW MORE
story-4
Every 2026 Ford Engine Explained

Here's everything you need to know about every Ford engine available for the 2026 model year.

By Brett Foote | 2026-06-05 12:58:01


VIEW MORE
story-5
10 Ugly Ford Trucks That We Still Kinda Love

Slideshow: 10 ugly Ford trucks that we still kinda love.

By Joe Kucinski | 2026-06-03 09:51:16


VIEW MORE
story-6
10 Things Every Truck Owner NEEDS (2026 Edition)

Slideshow: the best gifts for dads & grads

By Michael S. Palmer | 2026-06-03 15:43:58


VIEW MORE
story-7
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.

By Verdad Gallardo | 2026-06-03 11:38:36


VIEW MORE
story-8
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

Slideshow: 10 most expensive Ford trucks ever sold on Bring a Trailer.

By Joe Kucinski | 2026-05-27 16:24:34


VIEW MORE
story-9
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

Here's everything that has changed for the latest model year.

By Brett Foote | 2026-05-27 16:17:28


VIEW MORE