Why my van lost its power in the Rockies ?

Hi folks


Maybe someone know the answer for the question:
why my van lost its power in the Rockies ?



Shortly:

Van: 1992 Ford Aerostar, 3.0 litre engine, automatic
transmission, usually driven in Ontario, Canada
(altitude: ca 500 ft above sea level).
Trip: Ontario - Yellowstone - Grand Canyon - Ontario
+ sidetrips.
Load: 5 people (total 750 lb) and their camping gear.
Van loaded pretty full, but no trailer.

Observations:
Leakages of transmission fluid during hard driving
(climbing up hills, speeding, accelerating).
No leakages, when less power was neccessary
(driving with moderate speed at flat highway).
No leakages during stops and overnights.
End of above problems after return to lower altitudes.

Hypotesis: when driven at higher altitudes
the van used to significally lose its power (why ?).
That caused increasing in tranny workload (?),
hence tranny overheatings.

Anybody to confirm / negate / explain ?



Details:

Problems started in SD. It was transmission fluid leakage
during climbing hills at I-90 west from Missouri crossing
with 75-80 mph at the speedometer.
After cooling down and refilling the fluid, the van run
smoothly (however cautiously, at 50 mph) without any leak.
Also there was no leak overnight.

Problem returned in Black Hills, SD. Again tranny leaked.
But that time I noticed I could climb a hill (quite steep,
however) at 30-40 mph only. Above that speed
engine temperature gauge started to climb quickly to
a red mark. After slowing, temperature felt down.
If not slowed, tranny leaked.
Again, no leaks after cooling down and refilling.

Spoke to a tranny mechanic. He tested the van
and diagnosed that tranny is OK. 'Do not press
too hard' was his advice.

Third episode:
climbing Bighorn Mountain on WY-14, heading to
Yellowstone. Elevation ca 9000 ft. Really steep.
It took 1,5 hours to make 10 miles. Speed 20 mph,
seemed that the engine wasn't able to provide more
power to speed up. Every other mile or so there was
neccessity to stop and cool down the tranny.
Also: I used 3 qts of tranny fluid for refills.

Then I returned to Sheridan, WY, to speak with
a Ford dealership. Their diagnosis: tranny to replace
or rebuild. Mere $1900 or $2600. I declined both
solutions. After all, tranny functioned properly
except overheating. And I believed the new tranny
would not solve this problem.

Spoke to another tranny specialist. He test-drove
the van and confirmed, tranny is OK.
Also he suggested to test the engine, stating
it is too weak.

Spoke to engine specialist. He tested it carefully,
test-drove the van and found nothing wrong.
And it seemed to me, also, that the engine power
was OK during the test. So I started to think that
the problem is not permanent, but random.

Stripped from full faith in my van, I decided not
to try WY-14 again but to reach Yellowstone by northwest
entrance. I did it, however the climb on 191 was tough.
The van was able to make only 30-50 mph without engine
temperature gauge going to red. But it did it. Later
I drove all Yellowstone without a problem, regardless
of altitudes 7000-9000 ft. Slower speeds probably helped.

During the remain of the trip, several other episodes
showed me, that sometimes the van drives just great,
but there are numerous times, when it is incredibly
weak. For example, it was unable to drive 75 mph on
flat highway 20 in ID without a cloud of white smoke.
Or unable to accelerate quickly when entering a I-80
near Wells, Nevada. Or tranny fluid leakage because
of its overheating near Bryce Canyon (speed: 30 mph)
and in many other places.

However, what wondered me mostly, was: all the
weak-engine-and-leaking-tranny problems just vanished
after leaving Colorado during the return leg of our trip.
I.e., after driving down the 3000 ft altitude line.
Since then, I drove over 3000 miles without any problems
with engine power or tranny fluid refilling. So, it seems
obvious to me, that my van had a kind of mountain sick.
Who knows, what was it ? Who had similiar problems ?



Regards
Tadeusz

"aa" wrote in message
.. .
Maybe someone know the answer for the question:
why my van lost its power in the Rockies ?

Van: 1992 Ford Aerostar, 3.0 litre engine, automatic
transmission, usually driven in Ontario, Canada
(altitude: ca 500 ft above sea level).
Trip: Ontario - Yellowstone - Grand Canyon - Ontario
+ sidetrips.
Load: 5 people (total 750 lb) and their camping gear.
Van loaded pretty full, but no trailer.

Observations:
Leakages of transmission fluid during hard driving
(climbing up hills, speeding, accelerating).
No leakages, when less power was neccessary
(driving with moderate speed at flat highway).
No leakages during stops and overnights.
End of above problems after return to lower altitudes.

Hypotesis: when driven at higher altitudes
the van used to significally lose its power (why ?).
That caused increasing in tranny workload (?),
hence tranny overheatings.

Anybody to confirm / negate / explain ?


The atmospheric pressure in Colorado is a lot less than it is at sea level,
therefore, you can expect a little more leakage. The percent of oxygen in
the Colorado Rockies is quite a bit less than it is at sea level, therefore,
you can expect less performance from your engine unless it's electronically
fuel injected and has a computer to measure the lack of oxygen at those
altitudes. Next time you're in the Colorado Rockies (the higher the better)
get out of your car and sprint as far as you can. When you become "winded"
in short order, don't call a doctor, just take into consideration that your
body isn't used to the reduced oxygen in the air. Your automobile engine
falls into the same category. It's not a good idea to take an older lowlands
car into the high Rockies, you're lucky it didn't die up there! KM
--
(-:alohacyberian:-) At my website there are 3000 live cameras or
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"aa" wrote in message
.. .

Hi folks


Maybe someone know the answer for the question:
why my van lost its power in the Rockies ?



Shortly:

Van: 1992 Ford Aerostar, 3.0 litre engine, automatic
transmission, usually driven in Ontario, Canada
(altitude: ca 500 ft above sea level).
Trip: Ontario - Yellowstone - Grand Canyon - Ontario
+ sidetrips.
Load: 5 people (total 750 lb) and their camping gear.
Van loaded pretty full, but no trailer.

Observations:
Leakages of transmission fluid during hard driving
(climbing up hills, speeding, accelerating).
No leakages, when less power was neccessary
(driving with moderate speed at flat highway).
No leakages during stops and overnights.
End of above problems after return to lower altitudes.

Hypotesis: when driven at higher altitudes
the van used to significally lose its power (why ?).
That caused increasing in tranny workload (?),
hence tranny overheatings.

Anybody to confirm / negate / explain ?





Leakage of transmission fluid is often an indication of
it boiling, the torque converter slips a lot when climbing hills
generating much more heat. Transmission fluid is hygroscopic
meaning it absorbs water, old transmission fluid boils at a
lower temperature than fresh fluid.

If the fluid has never been changed then consider changing it and
think about getting a transmission cooler fitted if you have a
recurrence.

Keith

"alohacyberian" wrote in message
...
"aa" wrote in message
.. .
Maybe someone know the answer for the question:
why my van lost its power in the Rockies ?

Van: 1992 Ford Aerostar, 3.0 litre engine, automatic
transmission, usually driven in Ontario, Canada
(altitude: ca 500 ft above sea level).
Trip: Ontario - Yellowstone - Grand Canyon - Ontario
+ sidetrips.
Load: 5 people (total 750 lb) and their camping gear.
Van loaded pretty full, but no trailer.

Observations:
Leakages of transmission fluid during hard driving
(climbing up hills, speeding, accelerating).
No leakages, when less power was neccessary
(driving with moderate speed at flat highway).
No leakages during stops and overnights.
End of above problems after return to lower altitudes.

Hypotesis: when driven at higher altitudes
the van used to significally lose its power (why ?).
That caused increasing in tranny workload (?),
hence tranny overheatings.

Anybody to confirm / negate / explain ?


The atmospheric pressure in Colorado is a lot less than it is at sea
level,
therefore, you can expect a little more leakage. The percent of oxygen in
the Colorado Rockies is quite a bit less than it is at sea level,
therefore,
you can expect less performance from your engine unless it's
electronically
fuel injected and has a computer to measure the lack of oxygen at those
altitudes. Next time you're in the Colorado Rockies (the higher the
better)
get out of your car and sprint as far as you can. When you become
"winded"
in short order, don't call a doctor, just take into consideration that
your
body isn't used to the reduced oxygen in the air. Your automobile engine
falls into the same category. It's not a good idea to take an older
lowlands
car into the high Rockies, you're lucky it didn't die up there! KM

This is true but a 3 litre engine should handle this with ease
and this doesnt explain the transmission fluid loss. I suspect
the transmission was overheating. I have seen this a lot, usually
with vehicles towing trailers but a 750 lb load would do it.

Keith

I agree that there is less quantity of oxygen at altitude but what
mechanism do you propose to produce a lower percentage? FFM

alohacyberian wrote:

"aa" wrote in message
.. .

Maybe someone know the answer for the question:
why my van lost its power in the Rockies ?

Van: 1992 Ford Aerostar, 3.0 litre engine, automatic
transmission, usually driven in Ontario, Canada
(altitude: ca 500 ft above sea level).
Trip: Ontario - Yellowstone - Grand Canyon - Ontario
+ sidetrips.
Load: 5 people (total 750 lb) and their camping gear.
Van loaded pretty full, but no trailer.

Observations:
Leakages of transmission fluid during hard driving
(climbing up hills, speeding, accelerating).
No leakages, when less power was neccessary
(driving with moderate speed at flat highway).
No leakages during stops and overnights.
End of above problems after return to lower altitudes.

Hypotesis: when driven at higher altitudes
the van used to significally lose its power (why ?).
That caused increasing in tranny workload (?),
hence tranny overheatings.

Anybody to confirm / negate / explain ?



The atmospheric pressure in Colorado is a lot less than it is at sea level,
therefore, you can expect a little more leakage. The percent of oxygen in
the Colorado Rockies is quite a bit less than it is at sea level, therefore,
you can expect less performance from your engine unless it's electronically
fuel injected and has a computer to measure the lack of oxygen at those
altitudes. Next time you're in the Colorado Rockies (the higher the better)
get out of your car and sprint as far as you can. When you become "winded"
in short order, don't call a doctor, just take into consideration that your
body isn't used to the reduced oxygen in the air. Your automobile engine
falls into the same category. It's not a good idea to take an older lowlands
car into the high Rockies, you're lucky it didn't die up there! KM

"Canada Smiling" wrote in message
...
Think about it
the higher you go the less air you have there for the less power you have
the higher you go the less pressure you have there for more pressure
leaks ie transmission and oil leaks
for every 1000 ft up you should drop top speed by 5-10mph



Nonsense

I have driven over several 11,000 foot passes and according
to your thinking my top speed should have been around 25mph

That was not the case.

Keith

Keith Willshaw wrote:


I have driven over several 11,000 foot passes and according
to your thinking my top speed should have been around 25mph

That was not the case.

Gasoline powered vehicles loss 3-4% of their power for every 1,000 feet of
altitude because the air is thinner. I don't know where you were driving, but
the only time I have been through a pass over 10,000 feet the speed limit was
only 45 mph., so it would be hard to tell what the top end would be. This is a
direct result of the thinner air, hence less oxygen. Modern engines have oxygen
sensors to control the fuel - air mixture, but if there just isn't much oxygen,
even that isn't going to do much good. Turbo charged engines fare better in
high altitude because they can force more air into the system.

"Frank F. Matthews" wrote:

I agree that there is less quantity of oxygen at altitude but what
mechanism do you propose to produce a lower percentage? FFM

A turbocharger. The turbo charger in most engines runs of the exhaust, and since
there is less resistance in the thinner air, it will force more volume through the
system than can be done with a naturally aspirated carburettor.

"Dave Smith" wrote in message
...

"Frank F. Matthews" wrote:

I agree that there is less quantity of oxygen at altitude but what
mechanism do you propose to produce a lower percentage? FFM

A turbocharger. The turbo charger in most engines runs of the exhaust,
and since
there is less resistance in the thinner air, it will force more volume
through the
system than can be done with a naturally aspirated carburettor.


How does this provide a mechanism for explaining a lower O2 percentage
in thinner air ?

Keith

"Dave Smith" wrote in message
...
Keith Willshaw wrote:


I have driven over several 11,000 foot passes and according
to your thinking my top speed should have been around 25mph

That was not the case.

Gasoline powered vehicles loss 3-4% of their power for every 1,000 feet of
altitude because the air is thinner.

Which doesnt translate to 5-10 mph slower per 1000 ft

I don't know where you were driving,

Tioga Pass
Trail Ridge Drive

but
the only time I have been through a pass over 10,000 feet the speed limit
was
only 45 mph., so it would be hard to tell what the top end would be.


A hell of alot more than 45 mph. On trail ridge drive we probably
reached 55 with no sign of reaching the top end.

This is a
direct result of the thinner air, hence less oxygen. Modern engines have
oxygen
sensors to control the fuel - air mixture, but if there just isn't much
oxygen,
even that isn't going to do much good. Turbo charged engines fare better
in
high altitude because they can force more air into the system.


Sure but using your formula, which seems reasonable, at
10,000 ft we have only lost 30-40% of power

Keith