SOAZ said:Here are some RPM numbers with 4.88's in a 2001 Toyota 4Runner 3.4 Liter V6 and 255-85-16 Cooper ST's
ooh! Good stuff. That is the only thing I miss. Being able to go 85 and have the motor still sound like its barely turning. On the other hand if there was dust in the air it was enough to slow the truck down and kick it out of overdrive with that stock gearing and 255's. It was a :cow:Redline said:I'm going to have to mount my STs and test my RPM on my '06 4Runner and stock 3.73 gears. Get ready for some low numbers
SOAZ said:ooh! Good stuff. That is the only thing I miss. Being able to go 85 and have the motor still sound like its barely turning. On the other hand if there was dust in the air it was enough to slow the truck down and kick it out of overdrive with that stock gearing and 255's. It was a :cow:
SOAZ said:Here are some RPM numbers with 4.88's in a 2001 Toyota 4Runner 3.4 Liter V6 and 255-85-16 Cooper ST's
Redline said:You are exactly correct. Even with my V8, if my foot is too heavy or the road a little steep, some wind, or speeds too high, my tranny will shift out of O/D for 4th/direct. If it doesn't downshift because I'm 'light footing it' I lose lots of road speed. But it goes very well in 4th, or 3rd if needed, on big hills towing the Chaser.
Lower gears would be nice, I'm thinking 4.56, and they or may not cost me some MPG. I’m still not sure I will do gears and lockers, I'm still deciding how bad I need or want them on this Mall Crawler.
slooowr6 said:<hijack>
Please help me understand the way how O/D works on automatic. This is what I seen of my truck. Set crusing speed at 65mph.
on flat: ~1980rpm (Is this lock O/D?)
slight incline: ~2500rpm (5th?)
If I manually **** to 4th the rpm will jump to ~3000rpm.
Thanks -Alex
<\hijack>
Redline said:I'm going to have to mount my STs and test my RPM on my '06 4Runner and stock 3.73 gears. Get ready for some low numbers
slooowr6 said:It's a 5spd auto in a Tacoma.
Now it makes sense. I think/guess this is what happen.
From flat->long incline at 65mph.
5th locked(1980rpm) -> (SC kicks in) -> 5th un-locked.(2500rpm)
It's pretty cool that with SC the Tacoma never really need to shift out on 5th on long climb.
Thanks for the explanation!
madizell said:Perhaps my Nissan Frontier differs from the Tacoma enough not to be a direct comparison, but when mine shifts from 5th at around 1,800 or so rpm to 2,500 rpm, it is downshifting to 4th. I don't see more than a few hundred rpm difference at best as a result of torque converter changes within any given gear, and those changes are a sliding scale, not a leap from one range to another. Since it won't use "overdrive" in combination with any other gear but 5th, I assume that it is essentially a 5-speed auto transmission, with 5th gear ratio being less than 1:1, hence "overdrive." I have been able to verify 4th versus 5th on the Nissan because of the O/D lockout button, which forces the transmission to stay in no higher gear than 4th (otherwise shifts normally but won't use 5th), and the dash display changes from "D" to "4", showing which gear it is in. Or, if it has already shifted down and you engage the lockout button, nothing happens in the transmission but the dash display changes from D to 4, suggesting to me that the shift was a gear change, not a converter spooling up. Most small displacement engines won't pull a long incline without gear changes because of lack of torque. I know mine won't, 265hp notwithstanding.
madizell said:Perhaps my Nissan Frontier differs from the Tacoma enough not to be a direct comparison, but when mine shifts from 5th at around 1,800 or so rpm to 2,500 rpm, it is downshifting to 4th. I don't see more than a few hundred rpm difference at best as a result of torque converter changes within any given gear, and those changes are a sliding scale, not a leap from one range to another. Since it won't use "overdrive" in combination with any other gear but 5th, I assume that it is essentially a 5-speed auto transmission, with 5th gear ratio being less than 1:1, hence "overdrive." I have been able to verify 4th versus 5th on the Nissan because of the O/D lockout button, which forces the transmission to stay in no higher gear than 4th (otherwise shifts normally but won't use 5th), and the dash display changes from "D" to "4", showing which gear it is in. Or, if it has already shifted down and you engage the lockout button, nothing happens in the transmission but the dash display changes from D to 4, suggesting to me that the shift was a gear change, not a converter spooling up. Most small displacement engines won't pull a long incline without gear changes because of lack of torque. I know mine won't, 265hp notwithstanding.