03 D2: Red oil light turns on at the end of regular drive up mountain.

neuropathy

Active member
Mar 20, 2019
34
2
Santa Barbara, CA
Thanks, I’m running behind on this wondering which adapter will be needed to test oil pressure in an 03 D2 so I can get all my ducks in a row here. Any idea?
 

rovercanus

Well-known member
Apr 24, 2004
9,462
146
I believe the thread size is M20x1.5. You can get an M20 to 1/8 adapter. I think I got mine from Amazon.

Never mind, this isn't correct.
 
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neuropathy

Active member
Mar 20, 2019
34
2
Santa Barbara, CA
Thank you guys. I’m wondering if I should test the oil pressure with the oil that’s currently in it or if I should drain and change the oil with 15W-40 oil as recommended here. Testing the oil pressure will require buying a test gauge, which I don’t have - any recommendations for one with an appropriate adapter? Which plug or line will I remove to connect the test gauge?

When draining the oil, is it best to have the vehicle perfectly level or maybe slightly uphill since I noticed the drain plug is in the back of the pan? My driveway is very... not level. I’ve got some flattish areas although the truck might be leaning toward the passenger side. Or I could park it in an uphill part of the driveway. I could also go to a more flat area, but if I’m pulling off parts to clean the pickup pipe and sump screen, as well as replacing o rings, I’ve got to pick my place carefully.

Should I clean grime off the underside of the engine?

Would you use mineral spirits, brake parts cleaner, gasoline or something else to clean the pickup tube, oil pan and underside of motor?

Just bought the pickup pipe o ring and the pan gasket from British Pacific - I’ll start inexpensively by doing the oil drain, cleanup, o ring, gasket, oil change. Then I’ll have to drive the car and see how it is and probably test the pressure if needed. I’m trying to avoid buying a gauge for this since things are tough right now with rebuilding my house.

Thank you all. I’d be lost without you. I just replaced my purge valve and that seems to have resolved another issue. I’m feeling good about getting into this oil light issue now!
 
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neuropathy

Active member
Mar 20, 2019
34
2
Santa Barbara, CA
I found that the oil pressure switch thread size is M12x1.5 - does anyone have a recommended oil pressure test gauge? Prefsbky this would be one that includes the necessary gauge adapter. Will I need an o ring as well?
 

reelsretreat

Member
Jul 10, 2021
8
0
North Texas
Here's my problem. Had low oil pressure at hot idle. Rebuilt oil pump, not the problem. Rebuilt entire engine, not the problem. Found a guy who said to sleeve oil ports under rockers, not the problem (if the machine shop really did it). I'm a 2 years into this thing and still have the same low oil pressure at hot idle problem. It's a 4.0 GEMS engine. Any ideas would be appreciated.
 

JohnnoK

Well-known member
Mar 19, 2017
180
17
Cape Town, South Africa
Have you had your transmitter and gauge tested?

The Rover P5B and P6B were the original users of the V8s in 3.5 guise and they used to have the idiot light come on at hot idle and it was accepted as normal as long as it went out off idle.
 
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donniefitz2

Well-known member
Sep 15, 2020
106
42
Scottsdale, AZ
fitzventure.com
You wouldn't happen to be using a Fram oil filter would you? I made that mistake and my pressure light would come on for a few seconds on startup. Replaced it and the problem is gone. I'll never use Fram again.
 

MM3846

Well-known member
Feb 18, 2014
960
46
LI, NY
I had a basic Fram fail on me years ago, the filter element just let go from the housing. I've never run the orange ones since, but I've run the tough guard or ultra guard ones plenty of times without issue. Buying the cheapest of anything usually isnt the best idea in my experience.
 

reelsretreat

Member
Jul 10, 2021
8
0
North Texas
So I found out my mechanic put in 5w30. I started toying with viscosity. Went to Rotella 10w40, light still came on at hot idle. Went to Mobile 1 15w50, better yet but light still came on after a while. During oil changes noticed oil cooler lines leaking. Not sure if it contributed to problem, but replaced lines and put Liqui Moly 10w60, and haven't had a problem since, even at 100 degree temps outside. I finally have an everyday driver.
 

Swedjen2

Well-known member
Sep 12, 2018
552
111
California
So I found out my mechanic put in 5w30. I started toying with viscosity. Went to Rotella 10w40, light still came on at hot idle. Went to Mobile 1 15w50, better yet but light still came on after a while. During oil changes noticed oil cooler lines leaking. Not sure if it contributed to problem, but replaced lines and put Liqui Moly 10w60, and haven't had a problem since, even at 100 degree temps outside. I finally have an everyday driver.
there is such a thing as too thick. What happened with 20/50? Amsoil makes a 20/50 fyi.
 

reelsretreat

Member
Jul 10, 2021
8
0
North Texas
Since the 15w50 didn"t work, and the first number is startup viscosity and the second is hot viscosity, I don't see how a 20w50 would be any different than a 15w50 during the hot summer months since my problem was at hot idle, not startup.
 

reelsretreat

Member
Jul 10, 2021
8
0
North Texas
That was the first thing I did. Then rebuilt the oil pump. Then rebuilt the engine. Spent countless hours scouring the internet world wide for a timing chain cover/oil pump housing since mine was scratched up and the machine shop thought that was the problem. They are obsolete and finding one in better shape than mine is nearly impossible. Found a guy in Kansas who rebuilds old Land Rovers from the ground up. He suggested sleeving the oil ports under the rockers, which we did. Replacing the rockers was the other choice but he said very expensive. In the two years I've owned this thing I've learned way more about them than I ever thought I would need to. But long story short, since using the 10w60, my oil light hasn't even flickered in this Texas heat so I think I'm good to go.
 

DiscoHasBeen

Well-known member
Aug 7, 2016
808
166
Indy
Not to hijack this thread, but a question. So if a person wanted a way to check oil pressure without having to attach a gauge, or to install a gauge in the cab, but wanted to retain the idiot light, wouldn't something like this work? Plumbed in along side the sensor. It says it works with any media.

Wireless Pressure Sensor, 1/4”NPT, 100PSI (iOS) https://www.amazon.com/dp/B015G5639K/ref=cm_sw_r_apan_glt_fabc_6TMZ192KRQBJHVK3HH0N