Rattle at startup after switching to 5W20

[dave1251]

I agree at start up the oil is a lot "thicker" than a 20 or 30 grade. If the "rattle" was at operating temps I could maybe see how this could be a valid argument it would be a possibility, although not a likely one. I find that argument to make up for a mechanical or design flaw to use a higher grade of oil.

 

[mechtech2]

Another filter vote as my strong first guess.
But why?
Oil filters can have anti drainback valves in them. Like the name implies, when the car is off and there is no oil pressure, it hold oil from emptying out of the filter, and possibly some passages too.
The classic symptom of a faulty filter in this respect is a ticking on start up for a few seconds or so.

 

[mechtech2]

Another filter vote as my strong first guess.
But why?
Oil filters can have anti drainback valves in them. Like the name implies, when the car is off and there is no oil pressure, it hold oil from emptying out of the filter, and possibly some passages too.
The classic symptom of a faulty filter in this respect is a ticking on start up for a few seconds or so.

 

[Merkava_4]

Originally Posted By: Stephen_G
i recently switched my 2003 sable (speced for 5W20) to 5W20 from 5W30, and i noticed that on cold start there is a bit of a rattle at startup, sounds like valve train rattle. It has 171,000 on the clock right now.

Should i switch back to a XW30?


That's because 5W-20 is too thin to fill in the space between Surface A and Surface B.

Surface A --->|Oil Here|<--- Surface B

 

[ottotheclown]

Try like suggested another filter the one you have been using all along, then if nothing changes go back to what you were doing. Has to be the oil if you try a new filter and rattle remains.

 

[TFB1]

Originally Posted By: Stephen_G


it goes away after it starts, so i will probably just give it 15 secs after startup to let it stabilize.


If it's taking 15 sec to stop rattling, I'd be changing the filter today...

 

[aquariuscsm]

Originally Posted By: Merkava_4
That's because 5W-20 is too thin to fill in the space between Surface A and Surface B.

Surface A --->|Oil Here|div>


^^Exactly! Switch back to 5W-10W30.

 

[Zako2]

Originally Posted By: Brit33

Both are 5W so really should be the same at cold start up.
Is there is big difference in HTHS?


The number before W letter designates the _winter_ flow viscosity, as in below freezing. At normal above freezing temperatures, the 20grade (0-20 or 5W20) should flow better than 5W30 and probably 0W30. One good way to confirm this is to look at the kinematic viscosity at 40C, which is usually published. 20 grade oils have lower viscosity than 30-grade, regardless of what winter grade is.

 

[Zako2]

The Ford Vulcan engine was probably designed before anyone even expected the existence of 20-grade motor oil. If 30-grade works well for you, I would say keep on using it. Having said this, I personally plan to switch for one OCI a Taurus with a Duratec (originally speced for 5W30, later for 5W20) from 5W30 to 5W20. Why? The car takes lots of short trips, under 5 miles. It seems like cold start flow is more important in this case.

 

[jca]

Originally Posted By: Merkava_4
Originally Posted By: Stephen_G
on cold start there is a bit of a rattle


That's because 5W-20 is too thin to fill in the space between Surface A and Surface B.

Surface A --->|Oil Here|div>


So, if 5w-20 is too thin at ambient temperature then how can any oil be OK at 100ºC? I get that you're a thick oil guy, but this makes no sense at all.

 

[aquariuscsm]

Back when I had my 2nd 3000GT,it had BAD startup rattle with thinner oils,whether hot or cold. Bumped up to Syntec 50 grade and it eliminated it. The thinner oil would all drip back down off of the engine internals and back into the oil pan. Upon startup,you could hear the oil being pumped up,coating everything,and the noise being eliminated. When I started using the Syntec 20W50,a nice thick coat of oil remained on the internals,and no more starup rattle. I switched back and forth a few times to confirm this.

 

[friendly_jacek]

Originally Posted By: jca
Originally Posted By: Merkava_4
Originally Posted By: Stephen_G
on cold start there is a bit of a rattle


That's because 5W-20 is too thin to fill in the space between Surface A and Surface B.

Surface A --->|Oil Here|div>


So, if 5w-20 is too thin at ambient temperature then how can any oil be OK at 100ºC? I get that you're a thick oil guy, but this makes no sense at all.




Let me explain that to you. When engine is cold, parts are smaller than they should be (you know, thermal expansion). So, you have too high tolerances. Thin oil is not coating them with thick layer enough to prevent metal to metal contacts on start up.

Yes, thin oils are great for oil economy and help to start cars in extremely low temps, but are not the best possible thing for everything as they are worshiped as such here on BITOG.

 

[Stephen_G]

Originally Posted By: TFB1
Originally Posted By: Stephen_G


it goes away after it starts, so i will probably just give it 15 secs after startup to let it stabilize.


If it's taking 15 sec to stop rattling, I'd be changing the filter today...


It goes away immediately after it turns over, just give it 15 secs to get it all circulating before moving off. As a precaution.

Also i have not heard it lately, maybe it was a fluke?

 

[aquariuscsm]

The startup rattle in my 3000GT was bad! You could feel the pistons rattling within the cylinder walls until the thin oil reached them. I cringed every time I started it,until I used the Syntec 20W50. No more startup rattle,whether it was below freezing outside or the middle of the summer. I wish they still made that stuff. I`d bought it at Walmart for around $4 a quart. Wonder if the Classic Car 5W50 is as strong of an oil? Wonder also how it compares to Mobil 1 15W50,which I`m guessing the M1 is superior (jmo). I`ve also thought of giving the Napa 15W50 a try,to see how well I like it compared the the M1 15W50. Wonder why Valvoline makes the Napa in 15W50,but not the Synpower? But even at full price,the Napa synth is a bargain. Isn`t it around $5 a quart?

 

[pushrod]

My Ranger 3.0 has lifter clatter on a hot restart from the bleed down that occurs with 5w-20; therefore I use any SOPUS 5w-30 and it has not occurred since I switched. I think these roller lifters were also used in the old 302 V8 and were designed for 5w-30 weight.
I would keep the filter and do a 4 qt. change.JMHO

 

[Stephen_G]

Originally Posted By: pushrod
My Ranger 3.0 has lifter clatter on a hot restart from the bleed down that occurs with 5w-20; therefore I use any SOPUS 5w-30 and it has not occurred since I switched. I think these roller lifters were also used in the old 302 V8 and were designed for 5w-30 weight.
I would keep the filter and do a 4 qt. change.JMHO


that sounds like what mine is doing.

 

[badnews]

Why use 5W20 ?

Use a 5W30 or even a 5W40

this thin oil stuff is nuts IMO

 

[01rangerxl]

Originally Posted By: badnews
Why use 5W20 ?

Probably because Ford very prominently suggests 5W20 for this engine. It's on the oil cap, and it's the ONLY recommended oil in the manual. There is no temperature range chart, it just says use 5W20.

As I mentioned earlier in this thread, I used to pay no mind to the 5W20 recommendation. Then one morning the cam synchro went SCREEEEEEEEECCCHH...chirp, chirp, chirp, chirp. No more 10W30 for this Vulcan until it starts burning a significant amount of oil.

 

[DragRace]

Originally Posted By: badnews
Why use 5W20 ?

Use a 5W30 or even a 5W40

this thin oil stuff is nuts IMO


Use whats listed in the owners manual OP.Sometimes changing oil filters can cause startup noise,dont blame the noise on an oil.Secondly,badnews,if your so educated on why this particular motor should need a thicker oil,maybe you should contact a Ford Supervisor of Fuel and Lubricants Engineering and explain to them your reasoning,I'm sure they'd appreciate your wealth of knowledge.

 

[Stephen_G]

Originally Posted By: DragRace
Originally Posted By: badnews
Why use 5W20 ?

Use a 5W30 or even a 5W40

this thin oil stuff is nuts IMO


Use whats listed in the owners manual OP.Sometimes changing oil filters can cause startup noise,dont blame the noise on an oil.Secondly,badnews,if your so educated on why this particular motor should need a thicker oil,maybe you should contact a Ford Supervisor of Fuel and Lubricants Engineering and explain to them your reasoning,I'm sure they'd appreciate your wealth of knowledge.


Only version of this engine i would run 10W40 in, would be the flat tappet version my friends 1987 aerostar has (used through 1992) due to the fact that most 10W40 oil is thick enough to coat the flat tappets. I have roller tappets so it is not as big of a deal.