Automatics and offroading......

takza · Post by **takza** » Thu Apr 29, 2004 5:35 pm

Got to thinking and realized that the Tercel 4WD wagon with the auto might be the best bet:

* could put 15" wheels and tall tires on it and still have some torque off road due to the torque converter allowing lower effective gearing....espec if a higher stall speed converter was installed.

* the bigger diameter tires would probably help the autos gas mileage some also...it's only around 4-5 MPG less than the manuals.

Might know what I'm talking about...might not. :huh:

GTSSportCoupe · Post by **GTSSportCoupe** » Thu Apr 29, 2004 5:43 pm

Not for me! :rolleyes: Go manual or go home!

3A-C Power · Post by **3A-C Power** » Thu Apr 29, 2004 6:46 pm

Going to 3 speeds from 6 and having a torque converter, you would have no control compared to the manual. You would be stepping on the gas more and more trying to start off in a higher 1st gear, then eventually the wheels would spin.

icE · Post by **icE** » Thu Apr 29, 2004 7:46 pm

3-speed is ok, except for the fact that you're stuck in third most of the time. Offroad, it doesn't perfom too shabby - you don't hafta worry about shifting, you can concentrate more on where you're going. And if you do need to shift into other gears, just go from low, to 2nd, to drive (i had to do that when the transmission wouldn't shift when the tranny fluid turned to jelly). Auto rulz

takza · Post by **takza** » Fri Apr 30, 2004 9:00 am

3A-C Power wrote:Going to 3 speeds from 6 and having a torque converter, you would have no control compared to the manual. You would be stepping on the gas more and more trying to start off in a higher 1st gear, then eventually the wheels would spin.

My guess is that with the torque converter slipping, the actual 1st gear ratio would be similar to EL with the manual. But with an auto, when crawling at low speeds under load (up a hill), the engine speed might even be a little higher than using EL.

Somebody needs to install a tach on an auto wagon and find out......

We have two instances on this list of these auto trans lasting a long time...over 200K miles and 180K miles???

Not that I'm about to R&R my trans for an auto though.

Thereminator · Post by **Thereminator** » Fri Apr 30, 2004 12:02 pm

My first thought was that an Auto would be nice for medium conditions like crusing at 30-40mph,but for a rough constantly changing terian where you need lots of control,it wouldnt work well at-all.Still,Id like to see how well you could get out of ruts useing the first-reverce method in Auto.For that matter I wounder if there was ever any first-reverce-lockout linkcage made for the 6-spd? <_<

icE · Post by **icE** » Fri Apr 30, 2004 2:14 pm

my auto tranny has lasted 220,000 miles so far, lets make it to 300k

And i'll probably install a tach, even though u can pretty much tell by listening to the engine

takza · Post by **takza** » Fri Apr 30, 2004 3:07 pm

icE wrote:my auto tranny has lasted 220,000 miles so far, lets make it to 300k And i'll probably install a tach, even though u can pretty much tell by listening to the engine

I'd like to hear what they did to your auto trans when you had it worked on, what they recommended, and how it acts now. Just for info.

These Toyota trans must be put together pretty well.

A tach can tell you a lot. Like how your trans is shifting and when.

If you know what your engine speed is at say 55 MPH...you would know what size tire to buy to get the RPMs down. Just some ideas.

3A-C Power · Post by **3A-C Power** » Fri Apr 30, 2004 4:41 pm

Starting off in first with the torque converter is more like starting off in second with the clutch. The torque converter gives you a higher starting torque by transmitting the same torque the engine is putting out at the same speed as the transmission is going. When the clutch is slipping, it's doing exactly the same thing, except with dry friction instead of viscous friction. The torque converter isn't some magic box that gives you torque for free.

takza · Post by **takza** » Sat May 01, 2004 4:20 am

Somebody would have to put a tach in one to see what going on...but the issue with me is that of "crawling" up a incline and needing to keep the car's speed down in order to avoid damage, etc.

If you go bouncing up a rough hill over rocks, the drops onto them could do some real damage under the car.

With a manual you have what you have as far as gear ratios...I find that on a rough 15 degree slope 1200 RPM is about the least I can manage in EL and still make it up.

Would be interesting to see what an auto would do in the same situation. You are right about the "static" gear ratio of the auto in first gear...probably pretty high...but when the converter slips it's obviously lower. It will slip most under high load and low RPMs. Don't know by how much though.

Final drive ratio also depends on tire diameter too.

Also finding that my attempts at gaining MPG are likely giving me better engine torque at low RPMs...which increases what you might call "crawling power".

Getting about a 10-12% gain in MPG now.

Thereminator · Post by **Thereminator** » Sat May 01, 2004 12:57 pm

1200 RPM is a testament to EL and Manual in Gen.,and control trumps convienance every-time. <_< Torq and Mpg,Ill have to re-visit your article!