I was reading a letter in Popular Mechanics yesterday and a guy writing in said that his 2001 4.6 calls for 5w-20. He also said that it was hard to find and that the only place he could get it was at a Ford dealer.

Is this true?

 

Yes you must use 5w-20 and no the FORD dealer is not the only source. Walmart carries the Motorcraft 5w-20. Other companys will have their version of 5w-20 out shortly.

 

Simple question.
If your engine went bad and you couldn't prove to FORD that you used 5w-20 that they specify. Do you think they will honor your warranty?
I don't want to find out.
The heavier oil is bad for the engine based on the engineering specs, ask an engineer.
Also, any oil can easily go 5000 miles.

 

I suppose a .4 MPG increase is worth it to get the CAFE rating up for Ford, but I'd be worried about engine protection. For Ford, they only need the engine to live for 36,000 miles. I'm expecting a whole lot more out of my truck.

If Ford changes the recommended oil to to WD-40, should we switch to that?

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Danny
'98 F-150 Std., RC, SB, 4x2, 4.2L, 5-sp, 3.08, AC, speed control, rear slider.
Mods: Mobil 1 engine oil, Red Line D4-ATF trans fluid, Edelbrock IAS shocks, 50 Series Flowmaster, K&N with airbox mod, Perma-Cool electric radiator fan, Superchip, ASP underdrive pulley

 

That’s what I was wondering about, if Ford changed the oil specification just to get a little better efficiency then what was the down side to this decision. Did they trade engine life for better mileage and emissions?

Did for specify 5w-30 for earlier 4.6’s?

I don’t want to ruin my engine by using a heavier oil, but I also don’t want to get less life out of it because Ford called for a thinner oil.

 

I found Pennzoil 5w-20 at Pep Boys as well.

 

The engine design didn't change from when the 5w-30 was specified so I don't see how Ford can deny a warranty claim just for using 5w-30 over the 20 weight.

 

There is no difference between the engines spec'd for 5W20 or 5W30. The only difference is the 5W20 printed on the oil cap and the money in Ford's pocket from avoiding additional fines from the feds / EPA.

Sometimes you guys crack me up. If the oil meets the quality rating than your OK. Ford is now testing the 5W20 in older engines to see how it holds up ... they only want their dealers to stock one oil because some of the dealers are to inept to keep the two oils seperated. Also, the 5.0L, the 4.0L are not using 5W20 due to added engine wear when they were tested. During the testing on the modulars it was determined that there was "negligible" wear differences between 5W20 and 5W30, the difference fell in the favor of the 5W30 oil, although the difference was very small.

BTW - JDF, I am an engineer.

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2001 Ford F150 Supercab 4.6L
Airlift Rear Suspention with onboard compressor

 

Use 5W30 and make life easier on yourself. The 5W20 spec is the "recomended" spec, this was done so that when Ford sold you the vehicle they could claim a .4 mpg increase in fuel economy, which if you sell 1 million vehicles goes a long way to help on your CAFE rating. The other reason was to reduce emissions, the 5W20 oil is a "cleaner oil" by way of reducing drag on the engine. I use 5W30 and when the 5W20 becomes more widley available I might switch but I doubt it.

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2001 Ford F150 Supercab 4.6L
Airlift Rear Suspention with onboard compressor

 

Thank you for your responses, just a couple more questions

I heard that using a heavier oil can actually damage the engine. Would the difference between 5w-20 and 5w-30 be enough to cause premature wear?

Would a 5w-20 oil have to be changed more often compared to a heavier oil since the viscosity is lower?

 

I've only used 10w30. Had a 95 with the 4.9 and used 10w40 in the summer.

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1997 XLT Teal 4.6L Flareside 4x4 ORP. Automatic, Reg. cab, 3.55LS, tinted windows, bug deflector, Dual exhaust, K&N Generation 2 air filter, BullDog keyless entry/remote start, Modern 16" wheels, bedliner, Covercraft tonneau cover, White faced gauges, electronic shift on the fly, Clarion ADX5655z Double Din Cassette & CD, 4 Pioneer TS-A6865 speakers and superchip. Going to add headers.


Future mods: Supercharger, headers, NOS, tranny upgrade(heavy duty gears, clutch packs, etc.), performance torque converter, bore engine 30 over, new pistons, crank, and rods, performance heads, new L if they still make them and I like the way it looks, and a Z06 Vette or BMW Z3.




Click here to see more pictures

 

Valvoline makes a 5w-20 oil, I found it a napa auto parts

[This message has been edited by Don C (edited 04-19-2001).]

 

FastDEW,
Didn't you post previously to use the 5w-20 because you were an engineer and that we should use what FORD engineer's spec?
Sorry FastDEW.
It was nlp who posted. See older 5w-20 thread down the board.

[This message has been edited by JDF (edited 04-19-2001).]

 

This whole 5w20 issue is crap!! Does anybody make it in Synthetic yet? No. So why the heck should Ford expect anybody to do it? What a massive step backwards. Synthetic has been proven beyond the shadow of a doubt to be better for many reasons. Now they are telling folks to put 5w20 deinosaur oil back in their engines, so thehy see a .4% fuel mileage improvement? Makes absolutely no sense to me! Maybeee when someone actually comes out with full synthetic, then consider it. Until then? No way! If I was buying a 2001 model, the 5w20 dino oil goes out of my engine!

 

I have absolutely no idea what to do.

Ford say’s use 5w20 and other people say 5w30. With Ford’s long history of not giving a crap what am I supposed to think. I don’t care about a mileage difference. I just want my 4.6 to last 100,000.

If 5w20 will do that then I’ll use it, if I need to switch to 5w30 to make it last then I’ll do that. I also don’t want it to take a dump during the emissions, which is easy to do in Mass.

I haven’t gotten the truck yet so I’d like to get a good idea as to what to do before I start switching oil weight around in my new truck. I’m guessing that 5w30 won’t hurt it.