94 850: Is is possible to change the 2-1 manual downshift speed?

  • Thread starter Thread starter Doug Warner
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Doug Warner

I routinely downshift my auto trans to maintain speed without braking
in traffic and downhill.
I can get into 2nd by shifting to 1 at speeds above 25MPH, but if I
let the speed drop below 25, it downshifts to 1 with heavy engine
braking, a hazard in traffic.
For smoothness, I feel that the 2-1 shift should occur at 15 MPH.

Does anyone know if it's possible to lower this shift point (2-1 with
lever in 1) without installing a reprogrammed ROM?
 
**slightly off topic reply**

Brakes are cheaper then transmissions!



I routinely downshift my auto trans to maintain speed without braking
in traffic and downhill.
I can get into 2nd by shifting to 1 at speeds above 25MPH, but if I
let the speed drop below 25, it downshifts to 1 with heavy engine
braking, a hazard in traffic.
For smoothness, I feel that the 2-1 shift should occur at 15 MPH.

Does anyone know if it's possible to lower this shift point (2-1 with
lever in 1) without installing a reprogrammed ROM?
 
Doug Warner said:
I routinely downshift my auto trans to maintain speed without braking
in traffic and downhill. I can get into 2nd by shifting to 1 at speeds above
25MPH, but if I let the speed drop below 25, it downshifts to 1 with
heavy engine braking, a hazard in traffic. For smoothness, I feel that the
2-1 shift should occur at 15 MPH.

Does anyone know if it's possible to lower this shift point (2-1 with
lever in 1) without installing a reprogrammed ROM?
Click to expand...

What mode do you have the gearbox in, because I believe the economy / sport
modes change the speed at which the downshift occurs - I can't remember
which way round it is, but in one mode, the downshift should be a 25 mph, in
the other mode, I think it's 6 mph (quite a difference).
 
What mode do you have the gearbox in, because I believe the economy / sport
modes change the speed at which the downshift occurs - I can't remember
which way round it is, but in one mode, the downshift should be a 25 mph, in
the other mode, I think it's 6 mph (quite a difference).
Click to expand...
The downshift point is 25 MPH in economy and sport mode.
 
Doug Warner said:
The downshift point is 25 MPH in economy and sport mode.
Click to expand...

Ah well it must be different in your age of 850. I have a 98 S70 auto, and
from memory of reading my handbook, and actual use, there is quite a marked
difference between economy and sport mode, in the downshift to 1st when in
L. Recently I had reason to experiment with this, when on holiday, one of
the country lanes, had quite a long descent, that you couldn't really drive
down quickly, so needed the 1st to keep the speed down.

It's the same gearbox, between your 850 and my S70, although I think there
was the odd revision (possibly software only) from the early 850s (I did
once read somebody's account of their early 850 and the gearbox would
downshift, automatically, when off the throttle and descending a hill, for
engine braking - but I've only ever read one account of this).

Do you have your handbook, and does it say anything about this? I'm pretty
sure mine does. So the question, really is a slightly different
implementation - or the possibility that your sport / economy mode switch
isn't working? Can you confirm from the other characteristics, that sport /
economy mode is definitely making a difference?
 
"Douglas said:
I did
once read somebody's account of their early 850 and the gearbox would
downshift, automatically, when off the throttle and descending a hill, for
engine braking - but I've only ever read one account of this
Click to expand...
My 95 854T does this routinely on steep hills.

Rick
 
I hope that you don't take this the wrong way, but....I've always
wondered why people are do intent upon saving a few hundred dollars in
brakes at the expense of several thousand dollars worth of transmission.

Just as an aside, here in Las Vegas on certain downgrades, there are
signs posted that prohibit downshifting, like on Cheyenne Eastbound from
the Beltway through Summerlin.
 
......................................................... said:
I hope that you don't take this the wrong way, but....I've always
wondered why people are do intent upon saving a few hundred dollars in
brakes at the expense of several thousand dollars worth of transmission.
Click to expand...

Well for long descents, it's more about brake fade, than saving on
friction material. That's the only reason I'd use lower ratios.
Just as an aside, here in Las Vegas on certain downgrades, there are
signs posted that prohibit downshifting, like on Cheyenne Eastbound from
the Beltway through Summerlin.
Click to expand...

What's the thinking behind that?
 
Douglas Hall said:
What's the thinking behind that?
Click to expand...
All the signs I've seen are for commercial vehicles with "engine brakes"
("jake brakes") and are in or around towns and cities. We have one here in
town that reads "engine braking prohibited" but I've seen them worded with
"downshifting." Unmuffled engine brakes create that loud BRAPPP noise.
Muffled ones really aren't very loud.

Mike

Mike
 
Douglas said:
Well for long descents, it's more about brake fade, than saving on
friction material. That's the only reason I'd use lower ratios.




What's the thinking behind that?
Click to expand...
You know...I have absolutely NO idea.
Hey, this is Las Vegas where normal, rational thinking seems to fly
right out the window.
 
Douglas said:
Well for long descents, it's more about brake fade, than saving on
friction material. That's the only reason I'd use lower ratios.




What's the thinking behind that?
Click to expand...
As far as long descents are concerned, I can definitely see the purpose
of downshifting, but as far as downshifting while coming up to a traffic
light, it just seems totally counter-productive.
 
Douglas Hall said:
Well for long descents, it's more about brake fade, than saving on
friction material. That's the only reason I'd use lower ratios.
Click to expand...
I followed a car down a long mountain road, watching brake lights and
smelling burning brake pads all the way, expecting them to lose it
when the brake fluid boiled.. Fortunately, the slope ended before
that.

Also, it's the engine that absorbs most of the braking energy, not the
transmission itself. I suppose the torque converter converts some
kinetic energy to heat as well, but it's not a wear item. The heat
ends up in the radiator via the transmission cooler.
Engine braking puts no more wear on the trans than does normal
driving.
 
"........................................................"
As far as long descents are concerned, I can definitely see the purpose
of downshifting, but as far as downshifting while coming up to a traffic
light, it just seems totally counter-productive.
Click to expand...

I don't do that either. I use to to control speed on downgrades, and
to maintain slow traffic crawl speeds without braking every 10
seconds. Now, with a manual trans, I'd downshift, if I thought the
light might turn green soon, so I'd be in a good gear to accelerate
again. Otherwise, when the speed got too low, I'd just shift to
neutral.
 
Also, it's the engine that absorbs most of the braking energy, not the
transmission itself. I suppose the torque converter converts some
kinetic energy to heat as well, but it's not a wear item. The heat
ends up in the radiator via the transmission cooler.
Engine braking puts no more wear on the trans than does normal
driving.
Click to expand...

I'm glad that you agree with me. Downshifting for a red light which I
think is what the OP alluded to is just ludicrous. Very true what you
say about putting no more wear than normal driving. Every time that
bands and clutches engage and disengage there is wear. If you were to
downshift at every light, you would be creating twice the wear. Don't
delude yourself that the wimpy little coil in the radiator is doing a
whole hell of a lot, it's a marginal stopgap at best even when
everything is new.
I just gotta tell you something funny. Last Summer, one of the hottest
Summers on record here In Las Vegas, I went into the dealer for an oil
change. As I was waiting, I walked around the entire building to smoke a
cigarette (Don't go there). At the far rear of the lot, I saw this guy
with an electric "pusher" that he was using to push an XC wagon into the
very rear next to a wall. I walked over because I was interested in this
machine and when I asked what was wrong with the car that they were
pushing he just said "transmission...these hot days really bring them
in". When I asked how many of the cars in the lot were in for
transmission repairs, he pointed to the last two rows. TWENTY-THREE of
them, all under five years old. He then added, "Oh, we have fifteen more
in the storage lot".
No wonder that they now have Volvos go into neutral when you come to a
stop. Too bad it doesn't do it when the A.C. is on. With the kind of
driving that I do, I think that I'll have the trans flushed on a yearly
basis. I can just imagine a transmission failure on a 123 degree day
with clients in the car.
 
pushing he just said "transmission...these hot days really bring them
in". When I asked how many of the cars in the lot were in for
transmission repairs, he pointed to the last two rows. TWENTY-THREE of
them, all under five years old. He then added, "Oh, we have fifteen more
in the storage lot".
Click to expand...

Fortunately, manual transmissions don't break as easily, and a sizable
fraction of Volvo models (S40,V50,S60,V70 but not S80 or the XCs) are
offered with one. One more reason why slusheeboxes[*] suck.

[*]- The exceptions to this rule seem to be the AW7x boxes offered on the
old RWD Volvos. Those seem to be pretty bulletproof, and maybe even
better than the 4+OD manual trannies offered on the same cars.

-Andrew
 
"........................................................"
You know...I have absolutely NO idea.
Hey, this is Las Vegas where normal, rational thinking seems to fly
right out the window.
Click to expand...

How about the noise produced by semis when they downshift?
 
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