Mobil 1 Thread

J

jeanne penrod

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Jan 13, 1999
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Patrick, Before I begin my name is Jim not Jeanne,she was the
one who signed us up for the Net., Re:mobil 1 and Consumers Report citing
New York Cab study.In the seventies I had a meeting with the head mechanic
of Yellow or Checker Cab,at that time they were a National Fleet Account
with AC Spark Plug Div., lusting after a LARGE ORDER for Plugs & Filters I
was disappointed to learn they did not use Oil Filters on thier company
owned units.But I question Consumer Reports methods.These cab fleets use a
hours in use or days in use maintance for oil changes. Thier assumptions
were Company owened units run a minimum of 20 hrs. per day,Thus not
allowing any" sludge" or acid build up in the engines. So it would not
matter if they used Dino or Syn based oil.We tend to get in our coachs and
run all day,shut down,run another 6 to 10 hrs,shut down again.then park it
for a week.Definite sludge/acid/etc.Any of the Syns.will perform better
under our circumstances than Dino.But all of us have a comfort zone and
should rely on OUR own best judgement for Component/Product use in OUR
coachs. Jim Penrod Hangin out and bein cool in Lake Placid F
L A
 
>
>
> Patrick,
> Re:mobil 1 and Consumers Report citing New York Cab study.

> But I question Consumer Reports methods.These cab fleets
> use a hours in use or days in use maintance for oil changes.

One might also beg to differ that NY Taxi service ain't exactly "severe
service" when compared to a 455 pulling six tons of motorhome up the
Rockies, eh?

Patrick
 
NY taxi is about the most severe service that an engine will ever see. It
is not the steady RPM that kills an engine like pulling 6 tons up a
mountain, it is the stop and go and severe RPM changes that does it. Add the
constant starting of the engines (waiting for fares) and you have a real
killer for engines and trannys. The NY taxis run 24 hours a day 7 days a
week and put tons of miles on them.

>>
>>
>> Patrick,
>> Re:mobil 1 and Consumers Report citing New York Cab study.
>
>> But I question Consumer Reports methods.These cab fleets
>> use a hours in use or days in use maintance for oil changes.
>
>One might also beg to differ that NY Taxi service ain't exactly "severe
>service" when compared to a 455 pulling six tons of motorhome up the
>Rockies, eh?
>
>Patrick
>
>
Tom & Marg Warner
Vernon Center NY
1976 palmbeach
"The beautiful Mohawk Vally"
 
Thomas, I was referring to the demands of engine lubrication. There's no
way you're gonna' convince me that stop and go traffic and idling at the
curb(at least in a vehicle with a properly serviced and operating cooling
system) is anywhere near as hard on oil as a full throttle pull up a steep
grade with 35 mph forward speed. And yes, I have ridden in several NYC
taxis(an experience that is its own punishment), including a 4:00pm run from
Ft. Lee to LaGuardia(was convinced I was gonna' die that time).

BTW, why is NYC taxi service more demanding(on vehicles not passengers)
than LA, San Francisco, Chicago or Atlanta taxi service? Marketing hype
possibly? This whole NYC taxi testing stuff began because NYC has the
largest fleet of taxis in the U.S.(due to an extremely low rate of personal
auto ownership) and the 24-7 service made this an excellent test environment
for statisitical sampling reasons. The "most severe service" claim came
along in the 70's when an oil company used this test information in a
television commercial.

IMO, the "Most Severe Service Award" goes to Alaskan Pipeline service as
described by Fred Hudspeth a few months back.

Patrick

>
> NY taxi is about the most severe service that an engine will
> ever see. It
> is not the steady RPM that kills an engine like pulling 6 tons up a
> mountain, it is the stop and go and severe RPM changes that
> does it. Add the
> constant starting of the engines (waiting for fares) and you
> have a real
> killer for engines and trannys. The NY taxis run 24 hours a
> day 7 days a
> week and put tons of miles on them.
>

> >
> >One might also beg to differ that NY Taxi service ain't
> exactly "severe
> >service" when compared to a 455 pulling six tons of motorhome up the
> >Rockies, eh?
> >
> >Patrick
 
That Consumers Union oil study was one of the main reasons I ended my
subscription to the magazine, well that and the bread machine they
recommended. Anyway, there seems to have been many flaws in the Consumer's
test that makes it of little value (it was the most costly test they ever
did too). The cabs did not go through start up and shut down cycles. Cold
start I think we all agree is bad from a wear point of view. They ran the
engines long periods, maybe days in fact without shutting down. This would
allow the oil additive package to work at its best. Until the (dino) engine
oil reaches 160 or so, the additive package is largely ineffective.
Synethics work at their best at all temperatures. This shortcoming would not
be apparent in their test. Consumers ended the test after 60,000 miles. Not
enough mileage in my opinion. I have lots of experience with the Chevy
small block (they used the 4.3L, which is a 350 [5.7L] with the 3&6
cylinders missing). When built to specification, 60,000 would not cause the
type of wear to accumulate to test the lubricating capacity of one oil to
the next. I doubt the cab engines ever saw 3,500 rpm or heavy loading (I
mean a large percentage of the rated max hp. The engine they used was
probably only 165 hp, but in NYC street speeds, the engine rarely puts out
more than a tiny fraction of this on average). GM small blocks are designed
to run at or below 75% of their red line rpm rating. You go above this, you
are putting real stress on things. Again, if the engines were run under
more severe conditions of high load, high rpm, some oils might have proven
better. Then there is the issue of sample size and the variation in the
engines they used. Several failed during testing due to various causes not
related to oil. I don't think Consumers' test showed anything, and
definitely are not relevant to heavy duty operation like in a 12,000 lb RV.
Maybe dino oil will work just as good as synthetics for some applications
but I won't gamble with my engines, which I build myself, on anything less
than Mobil-1; especially in the GMC. walter bright, 76 GB.


- -----Original Message-----
From: Thomas G. Warner [mailto:warner]
Sent: Tuesday, April 27, 1999 8:35 AM
To: gmcmotorhome
Subject: RE: GMC: Mobil 1 Thread

NY taxi is about the most severe service that an engine will ever see. It
is not the steady RPM that kills an engine like pulling 6 tons up a
mountain, it is the stop and go and severe RPM changes that does it. Add the
constant starting of the engines (waiting for fares) and you have a real
killer for engines and trannys. The NY taxis run 24 hours a day 7 days a
week and put tons of miles on them.

>>
>>
>> Patrick,
>> Re:mobil 1 and Consumers Report citing New York Cab study.
>
>> But I question Consumer Reports methods.These cab fleets
>> use a hours in use or days in use maintance for oil changes.
>
>One might also beg to differ that NY Taxi service ain't exactly "severe
>service" when compared to a 455 pulling six tons of motorhome up the
>Rockies, eh?
>
>Patrick
>
>
Tom & Marg Warner
Vernon Center NY
1976 palmbeach
"The beautiful Mohawk Vally"
 
patrick I stick by my opinion that an engine running at a constant 4000 RPM
or so for long periods of time is not as hard as the stop and go traffic in
a large city. Constant RPM means high, constant,oil pressure. Its the
constant change in RPMs that cause STRESS levels of the cranks, rods, cam
etc that breaks down an engine. Those crazy drivers in NYC, jack rabbit
starts, fast breaking, weaving and dodging. Crazy, crazy crazy! Los Angeles
and other cities just as bad probably.

Want a really long lasting engine, run it at constant RPM and drive a
hydrostatic pump to drive motors on the wheels (hydrostatic lawn tractor) at
constant speed. the engine loves it and will last much much longer.

>Thomas, I was referring to the demands of engine lubrication. There's no
>way you're gonna' convince me that stop and go traffic and idling at the
>curb(at least in a vehicle with a properly serviced and operating cooling
>system) is anywhere near as hard on oil as a full throttle pull up a steep
>grade with 35 mph forward speed. And yes, I have ridden in several NYC
>taxis(an experience that is its own punishment), including a 4:00pm run from
>Ft. Lee to LaGuardia(was convinced I was gonna' die that time).
>
>BTW, why is NYC taxi service more demanding(on vehicles not passengers)
>than LA, San Francisco, Chicago or Atlanta taxi service? Marketing hype
>possibly? This whole NYC taxi testing stuff began because NYC has the
>largest fleet of taxis in the U.S.(due to an extremely low rate of personal
>auto ownership) and the 24-7 service made this an excellent test environment
>for statisitical sampling reasons. The "most severe service" claim came
>along in the 70's when an oil company used this test information in a
>television commercial.
>
>IMO, the "Most Severe Service Award" goes to Alaskan Pipeline service as
>described by Fred Hudspeth a few months back.
>
>Patrick
>

>>
>> NY taxi is about the most severe service that an engine will
>> ever see. It
>> is not the steady RPM that kills an engine like pulling 6 tons up a
>> mountain, it is the stop and go and severe RPM changes that
>> does it. Add the
>> constant starting of the engines (waiting for fares) and you
>> have a real
>> killer for engines and trannys. The NY taxis run 24 hours a
>> day 7 days a
>> week and put tons of miles on them.
>>

>> >
>> >One might also beg to differ that NY Taxi service ain't
>> exactly "severe
>> >service" when compared to a 455 pulling six tons of motorhome up the
>> >Rockies, eh?
>> >
>> >Patrick
>
>
Tom & Marg Warner
Vernon Center NY
1976 palmbeach
"The beautiful Mohawk Vally"
 
Hi Rick; I go toe to toe with them in the mean streets of NYC from time to
time. I have the same machine that many of them have (Caprice). What I mean
is my engine, like theirs, seldom sees more than 2,000 rpm even in hard
acceleration in the city and the majority of the time its at idle. While my
engine produces about 260 hp, in NYC I doubt its ever more than 125 max, not
much loading for an engine designed to go over double the rpm and hp. I
agree with you and others who have said that violent changes in speed etc.
put severe loads on the engine, but even in first gear, I have to get up to
40 mph to be in the peak hp range. All I know is my biggest worry is my
engine when towing 5,000# up a long, steep grade and other drivers
(including those cabs)when in NYC. Take care, walt 76 GB.

- -----Original Message-----
From: RickStapls [mailto:RickStapls]
Sent: Wednesday, April 28, 1999 1:12 AM
To: gmcmotorhome
Subject: Re: GMC: Mobil 1 Thread

In a message dated 4/27/99 7:34:12 AM MST, paa8394
writes:

> I doubt the cab engines ever saw 3,500 rpm or heavy loading (I
> mean a large percentage of the rated max hp. The engine they used was
> probably only 165 hp, but in NYC street speeds, the engine rarely puts
out
> more than a tiny fraction of this on average).

Walter,
Been a while since you rode in a New York taxi, eh? ;-) Does the phrase

"stop and go" ring a bell? When we visited the Big Apple a couple of years
ago, it was STOP!! and GO LIKE HELL! These engines get stressed.

Rick Staples
'75 Eleganza
Louisville, CO
 
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