4700 RPM all day on 5W20?

[mshu7]

quote: schism

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mshu7, I dont know why you are hesitant to give us info. I'd honestly like to know atleast the road/s you are taking that allow that kind of speed(assumed speed of atleast around 100) with little intervention from law enforcement, even with a first class radar detector. But if you really wish not to say, I'll respect that.

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You've got the wrong person. You're lookin for bulwnkl.

The info I gave was for my Mazda3 which has the same engine & trans.

 

[Ugly3]

Borrow another car for the road trip.

 

[Bob Woods]

MY three cylinder Geo Metro didn't turn that high, 3k rpm at 70mph in fifth. You must have an automatic, my wifes Geo Metro with auto turned 4k rpm at 70 mph.

 

[brianl703]

quote:

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Though I see not alot wrong with the 24v v6. seems pretty reliable.

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The 2.5L version of that engine is used in a car sold in Europe known as the Ford Mondeo. As far as I know the only real differences between the engines (other than displacement) are that the Mondeo has an oil cooler (and that I'm not even sure of).

 

[Quattro Pete]

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The info I gave was for my Mazda3 which has the same engine & trans.

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But the final drive is different: 4.105 for the 3; 4.388 for the 5.

I'm guessing they did that because the 5 is heavier and is expected to carry more load, so they wanted it to rev higher to stay in the powerband. Max torque is reached at 4500 rpm. Not sure what the overall curve looks like though.

 

[Palut]

slightly

Idaho and Montana are great areas for high speed. Montana really had it right when they removed their daytime speed limit. I remember last spring driving on I-15 through Idaho. I had averaged 85 most of the trip so far, and was sick of driving. Since it was a clear, dry night with perfectly dry roads, and there was a full moon, I was able to settle into a nice comfortable 100 mph. I'd see one car maybe every 10 miles, and I could see for at least 1000 ft on each side of the road. It was nice! Enjoy your trip bulwnkl!

 

[Gary Allan]

I would think low profile tires and fast and furious gearing is the cause here of all our anxiety over this rpm thing

The only thing that I think will occur here is that the life of the oil can be shortened.

 

[goodvibes]

I wouldn't worry about it. Personally I would dump the factory oil to get rid of any break-in or factory debri and put in the same thing. I would also try to vary my speed so that I didn't have long hauls at any given speed to be on the safe side but I bet it won't hurt if you do. If the temp stays good, so are you.

 

[UncleS2]

Wow, that's some pretty serious sustained RPM! I thought my car was kinda high revving. In 5th gear, my DOHC Mtx 97 Neon turns 3K rpm at 72 mph.

Honestly, I have no idea how the 5w20 would do under those conditions- but from the 5w20 UOA's we've seen, I suspect it might well do just fine. Of course, if it was my car, I might try to come up with some Schaeffer 5w30 for that trip.

 

[jonny-b]

Why don't you buy a bottle of Auto-Rx and use 3-4 0z with the stock oil? The Auto-Rx makes the oil-film stronger and helps keep the metal clean, so that the oil performs better. If you call Frank, you will have it in a couple of days. Have a nice trip.

 

[bulwnkl]

Thanks for all the replies, folks. I would change the oil prior to departure if we drove this trip. However, something at work just changed that pretty well puts the kybosh (sp?) on the whole trip.

Stuart, our '00 Neon has nearly the same gearing as your '97, though it's a different combination of 5th vs. final drive ratios. It's made similar trips before to great effect, but that was on Red Line 10W30.

 

[HondaMan]

I see you are not making the trip, too bad

I think what most are trying to get at is:

Have you geared the car in such a drastic way and/or are plan on running in 3rd/4th the whole trip vs. the simple fact that you plan on driving very fast and no modifications.??

If you where simply planning on driving very fast, I would have no worries because I doubt the RPMs would be consistent .... however if the car is geared or you drive in such at way that by the time your are barely pulling from the light your RPMs are way up there, then my pretiction would have been an engine with a much shorter life than usual.

 

[Accord2005NJ]

I know you said no 5W-30 oils but that is what I would put in. A good synthetic 0-30 or 5-30 oil. I am not sure why you are so opposed to 5-20 oils? Just because Ford says so? Ford - the king of recalls?

 

[adam123]

Personaly I would only trust a 30 weight oil for kind of rpm,Im by no means a engineer but I persoanly wouldnt trust a 20weights at those rpms for extended periods of time.

my 2 cents.

 

[AEHaas]

This is the exact situation where thinner is better. A US highway drive at high RPM is low load. A thinner oil will flow at a higher rate (see my chapters) and therefore keep the engine parts cooler. This is pressure pop off valve related.

MC is a great oil with moly and perhaps one of the greatest additive packages. I would not hesitate to go with it but would put in a fresh fill of oil. Red Line 5W-20 would be an option if you want a "thicker" 20 wt. oil, essentially a 30 wt. by HTHS standards.

aehaas

 

[bulwnkl]

AEHaas, I have wondered about this idea. I would think that the journal bearings would 'pull' more oil in at these higher speeds and so be okay. This trip, though not happening now, will happen at some time and likely many times during our period of ownership. The trip is not quite a classic US highway trip, but somewhat more akin to a European highway drive in many respects (including steep, high-altitude mountain climbs). Or similar to driving the Enzo at, I don't know, perhaps 170-175 mph (??) all day. Certainly the vehicle can go much faster, but it is at least revving and working to a sufficient percentage of its maximum so as to be noticeable.

Nevertheless, I agree with your basic concept here so long as the oil itself will not break down. Given that all the 5W20 oils certified to the Honda and Ford specs are at least semi-synth, I was thinking that they ought to be up to the task. As there are various things I may not be aware of about this scenario, I asked for input. I appreciate all I have received and I'll most likely just stick with the Pennzoil, Chevron Supreme, or whatever I have in when we do make the trip.

Have you ever used Lube Control? What were the results?

 

[msjanket]

My Toyota Corolla runs in 4th speed on the automatic trannie at 2100 rpm at 65 mph. ****, 45-4700 sounds incredibly high. I'd have thought that some trannie thingie would allow for running at 2500 rpm rather than 4700 or so...I am rather amazed..

Mike

 

[glennc]

One thing to keep in mind is that rotational forces vary with the square of rpm. So, if the engine is redlined at 7000rpm, then at 4500 rpm rotational forces are only 36% what they would be at redline.

Horsepower requirements vary fairly closely with the cube of speed. If the vehicle has a theoretical drag-limited top speed of 130mph (reasonable for the power output on this van), then at 100mph it is using only about 45% of the available power. In this case approx. 71hp.

Horsepower is torque x rpm / 5250. So at 4500rpm and 71hp the engine is putting out 82lb-ft of torque. The torque spec for this engine happens to be at that rpm and is 148lb-ft, so the engine will be putting out only 56% of its available torque.

There will be plenty of cooling airflow and mostly low temps.

So you have a surprisingly un-stressed engine. Of course on hills and into headwinds it'll be running harder, but these conditions would be intermittent and certainly anticipated by the manufacturer when developing the oil spec.

Of course it is all academic at this point, but interesting to consider.

- Glenn

 

[bulwnkl]

Indeed it is, glennc. As a resident of Colorado, you are of course very familiar with the difference between SAE net bhp rating (based on standard conditions, is it not?) and actual max available hp at higher elevations. I forget the rule of thumb; isn't it 10% decrease per thousand feet? So while I agree with your math, the arithmetic is somewhat off. I think it is clear that the actual numbers and percentages of maximum are considerably lower (and higher, resectively) than the examples listed. Very roughly half of the trip would see the engine working at or above 75% and often near/at 100% of its actual available power output. Actually driving this trip with our other car (lower lbs/hp ratio and lower Cd, though with somewhat taller gearing) validate this assertion. That is to say, the other car is near (and often at) WOT for a great number of those miles. What I don't know is whether the stresses correspond to percentage of actual available output or rated output.

Altitude also increases volatility of most substances, and so I thought the oil would be more likely to evaporate, oxidize, and/or break down in other ways.

These are some of the things I don't know for sure and a part of why I asked.

You're certainly right about temperatures at this time of year. At other times this is much more of a potential issue as we end up in a southerly locale.

As you say, all academic for now (though we'll be making the trip other times) but interesting to consider.

 

[speedtc]

You need to seriously need to get another car for the trip. Whatever you did to the car you messed up it's cross country ability.