Hey fellas. I work at a lube shop in Edmonton Alberta, and we were instructed that a vehicle recomending 5w20 has to use 5w20 oil, or you can damage the internal components in the engine. Something about a new type of bearings?, I think this is a bunch of malarky, can anyone give me some facts about this?

 

Probably wont hurt anything, but 5W20 has less polymers than 5W30. Less stuff added to the oil means the oil will stay longer at the same VI than a wider spread viscosity. I am sure more people will explain. I do believe they mainly do it for fuel efficency.

 

See why it says 5w20 on your oil filler cap and why the owner's manual does not allow any other oil weights:
www.epa.gov/otaq/cert/dearmfr/ccd0006.pdf

Do the new engines really have tighter tolerances:
http://www.machinerylubrication.com/...up=Lubrication

http://www.machinerylubrication.com/...up=Maintenance

 

I Have a 2003 4.0L SOHC My Filler Cap Says 5w-30w My Manual Says 5w-30w the dealer keeps insisting on 5w-20w. I am so confused I want to Screeeeeeeeeeeeem!!!!!!!!!!!!. All of the CAFE documents say All the new engines approved for 5w-20w should read 5w-20w on the filler cap. Anybody else out there going through the same thing?

 

I Have a 2003 4.0L SOHC My Filler Cap Says 5w-30w My Manual Says 5w-30w the dealer keeps insisting on 5w-20w. I am so confused I want to Screeeeeeeeeeeeem!!!!!!!!!!!!. All of the CAFE documents say All the new engines approved for 5w-20w should read 5w-20w on the filler cap. Anybody else out there going through the same thing?

 

Major car companies are interested in selling more Suv’s because that is what the public is buying. In order to make more cars the CAFÉ rating of the company wide fleet has to meet government guidelines or they are fined.
So they are motivated to make engines that get better gas mileage. Reducing friction in the engine is one way to do that. Going to a lower viscosity oil means less fluid shear and less horsepower to pump the oil. However it’s a double-edged sword. Less viscosity means more wear. I recently read an article in Lubes and Greases magazine about this.
The car companies have decided that 150,000 miles is the life of the engine. So they are balancing their CAFÉ rating against our engine life. It is really not a fair deal.
Personally I would never use 5w anything unless I lived in Alaska.

84 F150 I6 200K
83 Mercedes 300K
93 Mercedes 215K

 

Don't let them do it. I suggest you try a different Ford dealer or go somewhere else. As long as you have receipts showing 5w30 was put in they must honor the warranty--for sure if it is any Ford dealer, but they also should for some other place and even home oil changes, but to be safe go to a different Ford dealer. Once out of warranty, do it yourself. Frankly I would want 10w30 in there, preferably one without "Energy Conserving" on the can, which means a heavy duty motor oil like Chevron Delo or a high mileage oil like Valvoline Maxlife.

 

Hey, Anybody with a truck that specifies 5w20 that has installed a real oil pressure gauge, I'l like to know what the oil pressure does with the 5w20. Need to check hot at 2000 rpm after a long drive, say 20 miles, preferably in hot weather.

 

In all honestly 5w20 is probably just fine. A few years from now we will know for sure. The people who have had oil analysis done have not shown wear numbers that were out of line for the type or age of their engines.

On the subject of using other than 5w20 and causing harm to the motor I would have to say that I have serious doubts that running 5w30 would hurt it any more than running 10w40 in a motor that requires 10w30 .

Because of improvements in oil we don't have to rely on think lubes when thinner oil will provide similar protection and less drag on internals. Until 5w20 came out 5w30 was the oil everyone did not trust. 5w30 has been out for at least 20 years now and many engines using it out last the bodies they are in. If we went with the old theories we would all use 10w40 with a bottle of STP.

As for the ford dealer using 5w20 in an engine that says 5w30 on the cap, dealers usually think they know it all and do many non approved things. If I were you I would never go there for an oil change again.