2004 Land Rover Discovery

[M. Barrett]

Dumb question of the day. What type of oil do I use. I see what the drivers manual recommends, but I could have sworn someone told me to make sure I use non synthetic oil.

 

[joey]

you can use any oil that you like. If non synthetic, change the oil every 3k, if synthetic, I recommend every 6-8k depending on driving conditions.

 

[M. Barrett]

Thank you so much for your help. I didn’t know I could use either. Why would nonsynthetic be recommended over synthetic? I don’t drive very much

 

[joey]

Cost is the biggest issue... but more than anything with either oil, it is the filter that will cause you to need to change oil. Once the filter is dirty the oil will be dirty.

 

[M. Barrett]

Sorry to ask yet another question, but I’m trying to learn. Do you think 5w40 or 10w40 would work best?

 

[joey]

Depends on the mileage, I used 10w30 in my 2002 Disco my 1997 Disco I used 15w50 but it was abused.

 

[BeemerNut]

"Once the filter is dirty the oil will be dirty."

Please explain how Joey?
A dirty filter as you call it will still filter out particles in the oil provided how fine the filtering media material is with catching dirt (carbon) particles larger than the filtering media still keeping the oil clean.
A plugged filter or a person that's rev's the snot out of a stone cold engine in a cold climate with thick cold oil which can not flow properly through the filter's fine media then causing the filter to go into a bypass condition passing UNFILTERED OIL into the engine preventing oil starvation to the bearings and critical internal parts. A dirty filter will filter out smaller particles than a new filter leaving out a plugged up filter going into bypass mode. ......~~=o&o>......

 

[BeemerNut]

I see what the drivers manual recommends, but I could have sworn someone told me to make sure I use non synthetic oil.

Not a "dumb question".
First off if your vehicle (especially Land Rover's) has any damp, weeping or leaking oil problems while running regular "dino" oil from out of the ground and then switching to fully synthetic oil you will have larger oil leaking problems. Synthetic oils acts like penetrating oil looking for weak seals or hardened gaskets to get out marking your parking spots.

Second reply answering what weight of oil to use.
Depends, a low mileage engine under 30K miles or one at 90 to 130K miles use?
Higher mileage resulting in larger rod and main bearing clearances, worn rocker shafts all contribute to lower oil pressure reading in the heat in stop and go conditions. Add to this what climate your driving as well how hard your going to work the engine like across the desert in the summer pulling a trailer or winter in the snow no towing in 20*F temps? Thicker oils during the hot season with a higher mileage engine, thinner oils during cold winter time better to flow faster to the bearings internally. LR engines are the worst with establishing oil pressure during the mornings first cold start. This is where a Pre-Oiler comes in handy, a fully pressurized oiling system and wet engine internally before hitting the starter. Day one with new 4.6 I added a 3 quart Pre Oiler. Even after an oil change with empty one quart filter installed becomes a fully pressurized engine before starting.
Back to this oil business. Unless your stressing the engine working it hard like a race engine or turbo charged requiring that extra 40*F of oil protection synthetic provides vs regular "dino" oil on the verge of "coking up" (turning to carbon), synthetic has its benefits. For a lower stressed lower internal temps engine running a high quality filter and oil you shouldn't have any problems. Change at proper to your use mileage.

Another topic, if still running a flat tappet cam (older engines) not the roller cam with roller lifters of newer era engines there is trouble down the road slowly wearing down the cam and lifters. Cam and lifters Rover's weak items that are shot by 60K miles.
EPA removed zinc and phorphous from the oil to protect the Cat converter's longer life.
Yeah right, passing oil called a smoker yes it will destroy your converter but then that engine is already a POS. A normal clean running will not burn oil, smoke or have additives that shorten a converter's life per EPA BS. At 143K miles too clean passing smog tests, Magnaflow high flow cats, Borla exhaust.
Protecting my (aftermarket cam and lifters) I add Comp Cam'"Engine Break In Oil Additive" to my oil protecting the cam and lifters EPA had additives removed. EPA does not give a damn about your older push rod engines vs 99-100% now roller cam and rocker engines produced.

Valvoline (dino) 20/50 five quarts with 3 1/2 quarts 10/30 summer (mild 62*F up to 85*F).
Cooler winter Valvoline (dino) 48*F to 71*F 20/50 three quarts with 5 1/2 quarts 10/30.
Pre oiler and lines an increased oil capacity of 8 quarts 28 ounces. I add 12 ounces of Comp Cams "Engine Break In Oil Additive to the oil protecting the cam and lifters plus other highly stressed contact areas like the valve stem to rocker and push rod ends.
Everyone has their own special formula. I can just smell the ******* or "pooping wars" beginning about oils with my reply. Prost.....~~=o&o>.......