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Discussion Starter #1
When highway cruising, on cruise, the difference between "D"(3rd) and O/D is about 1000 rpm. But when climbing a slight grade the tach will sometimes increase by about 500 rpm and you can feel a slight downshift unlike the normal downshift to "D"........what's happening?? :?
I know enough about t/c's to know that full O/D has the t/c fully locked up......but is there a semi-lockup....between "D" and "O/D"?? Are they really 5-speeds....??
The automatics in both the 1st and 2nd gens do this....at least my 4wd ones did......
 

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When you are cruising at highway speed, the T/C will lock up, which eliminates the difference in speed between the engine and the transmission. When you accelerate, the T/C will unlock, and the engine will speed up a bit before the transmission does due to how a T/C works.
 
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I also noticed that these variable valve timing engines do not downshift as much when on cruise control...when compared to years ago...it was usually a waste of time to have the cruise on except on very flat roads.

I assume the improvement comes from the hi-tech aspect of computer monitoring and adjustments to fuel, valve timing, etc...

The RAV still downshifts more often than our Corolla since it is a bit heavier and has the higher drag coefficient. Still, it's nice to be able to use the function more often than on a long trip through Kansas. I even use it down on a 35mph river road that the police hunt on fairly often.
 

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Not many 4.2 post anymore so better get it while its hot! :lol:


I like the cruise in the RAV in general but with the amount of power available I find it really jumps on the throttle alot when the grade % is too great. ("blue" the stretch between Moncton and Fredricton is a waste of time to use it on)

I find the optimal speed is 105km/hr and it seems to have just enough left in the power curve to get where its going without too many high revs.

Just my pennies.
Later. M.
 

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Discussion Starter #5
Thanks for the replies, folks.....
BUT......no one has convinced me of what is happening......YET :shock:

Jeff: I agree with all you've mentioned but if the grade isn't too steep, the t/c will stay in this semi-locked state for as long as it takes to climb the hill, without falling back to D (3rd). If the drag increases, it will fall back to D and the rpm will go up ~1000 over what it is in full lockup.

RAV4HER: Are you saying this ~500 rpm increase is the V V T and not the t/c leaving the fully locked state??? The only trouble I have with that is the rpm shouldn't go up if the t/c is still fully locked up....Also know what you mean about cruise cntl and Kansas (flat)...

Mark: Agreed, the cruise cntl in these automatics is a "pos" and my biggest disappointment in a small SUV with 161 horses!!!(2.4L) Without cruise, I can climb Mt Thom without a single downshift and maintain speed...BUT...try it in cruise and it falls back to "4th ??" and "3rd / D" numerous times.......and I'm getting older and lazy and want a decent cruise cntl. Shifting is for the VW only :roll:
 

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Bluenoser said:
Thanks for the replies, folks.....
BUT......no one has convinced me of what is happening......YET :shock:

Jeff: I agree with all you've mentioned but if the grade isn't too steep, the t/c will stay in this semi-locked state for as long as it takes to climb the hill, without falling back to D (3rd). If the drag increases, it will fall back to D and the rpm will go up ~1000 over what it is in full lockup.

RAV4HER: Are you saying this ~500 rpm increase is the V V T and not the t/c leaving the fully locked state??? The only trouble I have with that is the rpm shouldn't go up if the t/c is still fully locked up....Also know what you mean about cruise cntl and Kansas (flat)...

Mark: Agreed, the cruise cntl in these automatics is a "pos" and my biggest disappointment in a small SUV with 161 horses!!!(2.4L) Without cruise, I can climb Mt Thom without a single downshift and maintain speed...BUT...try it in cruise and it falls back to "4th ??" and "3rd / D" numerous times.......and I'm getting older and lazy and want a decent cruise cntl. Shifting is for the VW only :roll:
Yeah the RAV's cruise control is not perfect, but if you've ever driven a Chrysler (that includes the Jeep, Dodge, Plymouth, etc..), the Toyota's cruise control is waaaay better. You would not want to be driving a Chrysler in Cruise control over hilly terrain (and not pay attention to your actual speed), the next thing you know you're being pulled over for speeding...

Cheers!

Philo
 
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Bluenoser said:
Thanks for the replies, folks.....
BUT......no one has convinced me of what is happening......YET :shock:
Like Jeff said.

I asked my dad the same exact thing the other day. When it feels like it's downshifting into 3rd and ½ gear, the lockup clutch on the torque converter releases and the engine speeds up instead of downshifting. It's magnetic, so that's why it feels like it 'shifts' into a lower gear when it releases/backs off. The lockup just keeps the two halves of the converter together, which eliminates slippage and improves efficiency (read: saves gas). Stepping on the gas just forces it to release. Or something like that. Staring at cutaway pictures of a torque converter and trying to understand how one works was a tad confusing for me, so I'm not sure I got that exactly right.
 

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I guess since the RAV has an Overdrive button, effectively it is actually a 6-speed (8 speed, if you count the Reverse).... That should explain the 1/2 gear downshift...(?)

Maybe that answers the question....

Cheers!

Philo
 

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Sorry "Blue" I didn't really answer your post completely. I sort of got off on a tangent.

I feel it too and the gears are like this.
1....2........3............4(o/d)........................then t/c lock-up. Its like 4 1/2 . It will lock at or above 60km/hr I believe as in most vehicles. Pressure sensitive. When the pressure is put on the tranny the t/c unlocks and your just in 4th 500 rpm (I see it as maybe 300rpm) more @ 100km/hr. When you hit the pedal it will quickly pop back into 3rd and then the RPM jumps to 3500 or so and then you're suckin' back the gas!

All normal. When you have an engine with gobs of torque this in not such an issue. A heavy V6 or 8 is where this becomes smooth. Any 4cly is pretty much the same way. I have had Honda, Chrysler(2), VW, Ford and now this.....Pretty much all the same. The best for not doing this was Ford (WindStar 3.8L) and 2nd would be the Accord.

Hope this helps.
Later. M.
 

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Discussion Starter #10
OK......I've been under a misconception :? ......that 4th = O/D = t/c locked up..... So "in effect" we do have a 5 speed automatic......
For years I thought it was 1...2....3(D).....t/c locked(OD)... :oops:
Now you see why I wasn't getting what you were saying.. :roll:
Thanks a lot!!!.......now I understand the shifting and what I'm seeing on the tach.......
Too many years of driving a standard and not paying attention to what was happening in the world of automatics......they slipped an extra gear in there when I wasn't lookin'...... :lol: :lol: :lol:

Next question for the experts: :wink: Is there a sensitivity adjustment on a RAV's cruise control module and where is the module.....I'd like to make some small adjusts to see if I can reduce the number of shifts back to "D"......I can live with it falling back to "O/D" but not "D".......
I gotta get a Haynes manual....
 

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The module is located just behind the coolant overflow tank (towards the drivers seat). It has two cables sticking out that lead to the other throttle controls and gas peddle. The cover just pops off but you're on your own with the adjustment thing. Maybe its possible but its not something I know much about.

I think you can see it in the picture I have in the album with the CAI.

Later. M.
 

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Marcutio said:
Sorry "Blue" I didn't really answer your post completely. I sort of got off on a tangent.

I feel it too and the gears are like this.
1....2........3............4(o/d)........................then t/c lock-up. Its like 4 1/2 . It will lock at or above 60km/hr I believe as in most vehicles. Pressure sensitive. When the pressure is put on the tranny the t/c unlocks and your just in 4th 500 rpm (I see it as maybe 300rpm) more @ 100km/hr. When you hit the pedal it will quickly pop back into 3rd and then the RPM jumps to 3500 or so and then you're suckin' back the gas!

All normal. When you have an engine with gobs of torque this in not such an issue. A heavy V6 or 8 is where this becomes smooth. Any 4cly is pretty much the same way. I have had Honda, Chrysler(2), VW, Ford and now this.....Pretty much all the same. The best for not doing this was Ford (WindStar 3.8L) and 2nd would be the Accord.

Hope this helps.
Later. M.
Hmm, okay...
I've tried hitting the O/D button in 2 (but haven't tried it in other gears, so I assumed it does the same for all gears, inc. reverse), and it downshifts, never really paid attention to the difference in RPM though... I guess I'll have to check the tacometer when I try it again... For all I know, this is probably all in the owner's manual, maybe I should go take a look....:lol:

Rav on! :arrow:
 
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