Go Back   DodgeForum.com > Dodge Vans & CUVs > Dodge Ram Van
Sign in using an external account
Register Forgot Password?


Dodge Ram Van The full size Dodge Ram Van that showed that we can go and do as we please. Discuss the Dodge Ram Van here today.

drop in oil pressure in a 3.9

Reply
 
 
 
 
Thread Tools Search this Thread
  #1  
Old 06-10-2012, 04:52 PM
dadof4 dadof4 is offline
Registered User
Garage is empty, add now
 
Join Date: Jun 2012
Posts: 1
Default drop in oil pressure in a 3.9

have a 1999 dodge ram van 1500 with almost 90000 miles after being driven awhile and warmed up when coming to a stop the oil pressure gauge drops to 0 really fast. There is no abnormal engine noise of any kind. Could this be the oil sending unit and if so where is it at?
This ad is not displayed to registered and logged-in members.
Register your free account today and become a member on Dodge Forums!
Reply With Quote
  #2  
Old 06-10-2012, 07:14 PM
sparkzz's Avatar
sparkzz sparkzz is offline
Professional
Garage is empty, add now
 
Join Date: May 2006
Vehicle: '94 B250 extended cargo van 212,000 m. 2000 B3500 Hitop Maxivan 180,000
Location: New Orleans area
Posts: 201
Ken Luther
Default

Try changing oil and filter first. You might have a cheap oil filter problem.
Reply With Quote
  #3  
Old 06-12-2012, 06:44 PM
DoubleWasp DoubleWasp is offline
Rookie
1998 Dodge B-Series Van
 
Join Date: May 2012
Vehicle: 1998 Dodge B3500 Wagon Van
Location: Miami, Florida
Posts: 95
Default

Change the oil. When I got my van, changing out whatever was in there with a Mopar filter and Mobil Super 5000 oil netted me 30-40 lbs. of oil pressure back.
Reply With Quote
  #4  
Old 06-12-2012, 09:55 PM
landyacht318 landyacht318 is offline
Record Breaker
Garage is empty, add now
 
Join Date: Aug 2007
Posts: 1,025
Default

The reason I installed a mechanical oil pressure gauge is because the dashboard ones are slow and inaccurate at best.

I was gonna buy a real tester but a dashboard gauge was less money. I 'T'd' the line so that my stock gauge still works. The Dash gauge is about 45 seconds behind the mechanical which responds nearly instantly to increasing RPM

When cold, the max PSI is 68 PSI at 800 rpm, or at 4000rpm. 68psi is the oil pump relief pressure.

When hot this drops to ~63 psi

But at 550 rpm hot as it gets idle, I get 18 PSI with M1 TDT 5w-40 in the sump.

63 PSI is reached, when hot, at 1900 to 2100 rpm.



My factory service manual says 8 to 40 psi at idle is acceptable.

Some oils shear out of grade with age and abuse.

Sometimes fuel dilution in the oil will thin the oil and reduce it's viscosity so less psi makes it to the sender.
Reply With Quote
  #5  
Old 06-12-2012, 11:55 PM
blackvan's Avatar
blackvan blackvan is offline
Captain
2000 Dodge RAM 1500
 
Join Date: Mar 2012
Vehicle: 2000 Dodge Ram 5.2L Regency conversion
Posts: 697
Default

Quote:
Originally Posted by dadof4 View Post
have a 1999 dodge ram van 1500 with almost 90000 miles after being driven awhile and warmed up when coming to a stop the oil pressure gauge drops to 0 really fast. There is no abnormal engine noise of any kind. Could this be the oil sending unit and if so where is it at?
I would say it's either low on oil or there may be a problem with the oil pickup. When mine got a little over a quart low last year my oil pressure gauge would drop to 0 on hard stops and the check engine light would flash on for a second. After a second the oil level would recover and the pressure returned. Safe to say I keep a closer eye on the oil level now
Reply With Quote
  #6  
Old 06-14-2012, 11:20 AM
funair02's Avatar
funair02 funair02 is offline
Veteran
2003 Dodge Ram Van 1500
 
Join Date: Mar 2012
Vehicle: 2003 Dodge Ram Van 1500 Elk Conversion 3.9
Posts: 354
Default

are you sure you aren't dumping coolant from the intake or head gasket into the pan? That would cause your problem. Just a thought..BTW coolant settles below oil...
__________________
Funair - Tampa Bay, FLA-USA#1
2003 (2002) Dodge Van 1500 Elk Conv - fun times
2006 Jeep Grand Cherokee Limited - 5.7 Hemi
Reply With Quote
  #7  
Old 06-14-2012, 12:32 PM
iodj44 iodj44 is offline
Professional
1994 Dodge B-Series Van
My Garage
 
Join Date: May 2011
Posts: 103
Default

A mechanical gauge will help you figure the problem, at
the moment the true oil pressure is unknown.

The factory gauge is just not trust worthy.
Reply With Quote
Old 06-14-2012, 12:32 PM
Reply
 
 
 




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

Forum Jump

Join DodgeForum
Advertising

Featured Sponsors
Vendor Directory
Our Sponsors
All times are GMT -4. The time now is 12:28 PM.

Internet Brands, Inc.


Contact Details & Emails

Search Engine Friendly URLs by vBSEO 3.5.2