I picked up my 5 speed BCP 06' on Friday and the dealer didn't have my options in stock (another issue).. Anyway, I was given a xB today as a loaner that had an auto tranny. Here's the issue..

Auto Tranny at 80mph was 3200 rpm.
My 5 speed at 80 mph is 3900 rpm.

Both are 06 models.

No wonder the auto is rated at 2mpg better than the manual on the highway.. It's spinning where it should. I'm just wondering why the 5 speed tranny isn't spinning in the same range as the auto does, at the same speed??

 

Interesting. How is the exelleration with the 5-speed vs the auto?

 

For that first couple of weeks, it was hard to keep the front wheels from chirping in 1st and 2nd

 

It is because the auto has a tourque converter, while the MT trans does not.

A MT xB runs almost a full second faster through the 1/4 mile than the auto........

 

I'm fully aware of how a manual and auto tranny work.. My question is, why are they geared so much differently?

Acceleration with the manual is much stronger than the auto, but that's expected with such lower gearing. It' wouldn't be as much of a difference if they were geared the same and both turned the same RPM at the same road speed.

If they're trying to grab gearheads by shortening the gearing on the manual, so be it, but since they don't normally have a 5 speed to demo, how would anyone know the difference?? Hell, I didn't figure on this much of a difference (18%) between the two different trannys.

I bought the 5 speed because I like 5 speeds. I've owned around 20 cars in my lifetime and all but 3-4 have been manual..

I think I know what the problem is... I'm old...

 

>I'm fully aware of how a manual and auto tranny work.. My question is, why are they geared so much differently?

So that Scion can claim better mileage with the auto tranny than with the stick and therefore sell more autos.

Cynical? Moi??

>I bought the 5 speed because I like 5 speeds. I've owned around 20 cars in my lifetime and all but 3-4 have been manual..

AWRIGHT!! Sticks RULE!!!

>I think I know what the problem is... I'm old...

HOW old?!? I'm 52 (almost).

Someone should start a SOFa club (Scion Old-Fart's club)

-Don (SOFa #1)

 

Oh, I think you're onto something there!!!

Kinda like making gas $3 for a month, so that $2.50 seams like a deal???

 

it is actually because of a difference in the final drive gearing.....

 

I chose the automatic because it didn't rev so high on the freeway. The stick reminded me of my'85 Corolla GTS that always was reving high and had me wishing I had another gear. Sign me up for the SOF club. This 50 Y/O used to be a geezer, but now I'm an XBeezer!

 

It's too bad it's not a six speed. I always feel like a need to shift again after I'm in 5th.

 

Manual:
I have the manual and 80 is exactly 4000 rpm.

Auto:
Looking at the 4th gear ratio for the automatic in the table below, it gives 23.5 mph per 1000 rpm, so the rpm at 80 mph is actually 3400 rpm.
From Car & Driver (automatic trans.):
Gear ... Ratio ... Mph/1000 rpm ... Max. test speed
I ........ 2.85 .......5.8 ..............37 mph (6400 rpm)
II ....... 1.55...... 10.6 .............68 mph (6400 rpm)
III ..... 1.00 ..... 16.4 ............103 mph (6250 rpm)
IV ... ....0.70 .... 23.5 ............103 mph (4400 rpm)

Here are the gear ratios for each transmission:
Manual Ratios
1st 3.545
2nd 1.904
3rd 1.310
4th 0.969
5th 0.815
Reverse 3.250
Differential Ratio 4.312
Combined Final Drive (5th gear) 3.514

Automatic Ratios
1st 2.847
2nd 1.552
3rd 1.000
4th 0.700
Reverse 2.343
Differential Ratio 4.157
Combined Final Drive (4th gear) 2.910

At any speed, the automatic RPM in 4th gear will be 17% lower than the manual in 5th gear. Lower RPM means less horsepower and torque at any speed.

The automatic is for those who want economical communting and traveling, while the manual is for those who want performance and control of the transmission.

On long steep Interstate hills most people would appreciate the ability of the manual to maintain speed in top gear. On twisty 2-lane mountain roads, they would also appreciate the additional power and control offered by the manual.

 

I agree with the idea that it's to make the automatic as attactive as possible. It is like there is no trade-off to getting auto. The way it's geared, only benefit for manual is peppier acceleration. This may be closer to the reason some customers chose manual over automatic.

Forget the 6th gear, I just wish 5th gear were higher, a 5mph gap between 4th and 5th is almost worthless. I would rather shift into 5th at 50mph and have the lower cruising RPM. I guess it just wasn't worth the effort to make another C-series tranny just for the bB/xB.

 

i hate that the manual is geared like that. Almost makes me not want to drive it on the highway with the way that it screams. They need to offer a final gear that you can swap into the manual for nice highway cruising.

 

the worst part about the manual on the highway is that at 75mph there is no power! you have to down shift to 4th or even 3rd to get past something quickly. i had a 97 jetta 2.0l before this and in 5th gear all i had to do was push the gas alittle and i coudl go from 65-85 in seconds.

 

hmmm. interesting info for the prospective xB buyer. I am only looking to buy a new vehicle because of gas prices (currently rolling an F150 Supercrew) and was planning on getting the MT, assuming slightly better mpg. Either way, the xB is going to blow away my truck, and I guess I would probably prefer the little extra zip you can get with a manual.

 

deff get the 5spd...its not nearly as bad as some say. plus once you turn the stereo up you dont here the engine much anyway haha. and like you said...it will blow your truck away even if you drive it at 110%

 

Along with the extra zip comes more fuel consumption. I own the auto and wouldn't for any reason go to a manual. I feel I have more control over shift points with the auto. Reason is that with less actual accelerator usage my auto shifts in the low rpm range. Usually this is below 3k rpm. Now you do loose the zippiness but that's ok. I didn't buy it to be fast. As for uphil driving or passing on the highway, the auto has a neat little overdrive on/off button on the shift. Bump that and it downshifts to give you plenty of power to climb or pass. With traffic jams and city driving I wouldn't trade my auto for 2 sticks.

 

I'm concidering buying a Scion Xb but I'll tell ya having to hold the engine RPM at 3500 or higher for highway travel scares the life out of me!! I simply can't see how these engines can hold up. While as far as cars go the 14-16K you spend on an Xb is really really reasonable I still believe its still alot of money and should be expected to run trouble free for at least 100K miles. i guess what I'm asking is should I worry about durablity if I drive it alot on the highway??

 

Most small engine cars turn high rpms at freeway speed. My wifes civic turns almost 3500 at 75. The engine must turn this high to have the torque needed to keep the car at such a high speed. Her civic has 180000 on the clock and she drives 30 miles one way every day to work at 80 mph and has done so for 5 years. Now a friends dad has a 92 tercel that has over 300k on the clock and has always seen the highway. He drives almost 100 miles to work everyday and it turns over 3500 rpms at 75. These engines are made for it. I wouldn't worry.

 

As to hill-climbing with the automatic, pushing the little O/D button drops the auto transmission into third (which also has the torque-converter-lockup feature, same as 4th), which gives just slightly less aggressive overall gearing thaan dropping the 5-speed into 4th (4.16:1 as opposed to 4.18:1).

The auto when in 3rd climbs as well as the stick in 4th, in other words.

I just did a bit of cross-country driving across a couple of mountain ranges (Seattle area to Hamilton, MT and back) and had no problems with ANY hills, including the Vantage Hill (I-90, westbound, Vantage, WA to Ryegrass rest stop) which climbs 2000 feet in just under 10 miles in one continuous shot.

(The auto is much more relaxed zipping through Montana at a continuous 80MPH in 97 degree temps with the A/C on than the manual.)

The stick is peppier, but the auto is a bit better highway cruiser.

Tom