Why does everybody want to see 6 speed trannys. I'm not sure there is much of a performance gain with them. Here is a list of down falls:

-More moving parts
-Greater complexity to service
-More shifting (up and down hills)
-More shifting = more heat= more damage

Any comments good or bad, lets hear them!

 

Better mileage and more performance because the engine stays in the optimal horsepower/torque rpm range longer.

 

Vochy, don't forget, more $$ too!

 

2 overdrives = better mileage

closer gear spacing, allowing engine to stay in sweet spot even after shifting, as opposed to having a big rpm drop and lugging (especially when towing).

Using the Toyota 6sp as an example, 1st is lower than our 4sp, allowing better off line acceleration/power, gears are more closely spaced, and there are 2 overdrives, allowing a lower rear-end gear without sacrificing mileage.

 

I've had the opportunity to both drive and be a passenger in a Navigator with a 6 speed trans and I like it. It might take a little getting use to it. I didn't notice any issues with it down shifting and up shifting while stuck in traffic going between 30 and 60 mph.
With the extra gears normal take off is much better and the engine doesn't lug like my current 06 F-150.

 

Because four speeds are like, so totally 80's already.

 

IMO more moving parts are bad. maybe i'm just stuck in the past? It just seems like transmissions are following the path of razor blades. 3 blades work for me. I tried the more expensive 4 and 5 blade razors but found any increased performance from them wasn't worth the cost.

In my 06' 5.4l, I found that the Torque converter lock up at a high enough RPM to get into the torque curve and has very strong off the line pick-up. gearing up any more would be a waste. IMO!

 

I tried the more expensive 4 and 5 blade razors but found any increased performance from them wasn't worth the cost. You got that right. Try buying those replacement blades yet? What a rip off. As for the new 6-speed at what speed would the 6th gear kick in at? In my Ford the 4th gear is around 40 mph.

 

hey vochy! test drive a new expedition and you will understand the 6 speed!

 

Arguing against more gears doesn't acknowledge the realities auto makers face with getting their fleet mileage numbers higher. The number of gears in the case of a automatic transmission does not impact its lifespan. Today's 4 and 5 speeds have longer life than than the 3 speeds of 20 years ago.

 

how bout you spend less time using each gear so it'll last longer?

Better performance and mileage are enough to justify a small price increase (if there even is one) and its been proven to work in the expy, so there isn't going to be any reliablity issues. I don't see a problem.

 

"how bout you spend less time using each gear so it'll last longer?"
-captin

I was under the impression that shifting does more damage to wear components like clutch packs, than spending time in a gear.

"Today's 4 and 5 speeds have longer life than than the 3 speeds of 20 years ago."
-webmaster

Thats because todays technology allows for the manufacture of better components. 4 speeds of today will likely out last 4 speeds of 20 years ago. Or maybe they won't.

"2 overdrives = better mileage"
-laketrout

I dissagree, my girl friend drives a 96' contor which only has a 3 speed tranny in it. for a car of its size it gets very good fuel economy (30 mph). and as for the six speeds keeping the RPM's in the sweet spot I beleive (correct me if im wrong) the the 4 speed in my 06' has clutching action between gears to keep the RPM's in a sweet spot.

People is all a marketing ploy, if your tranny has 6 speeds they can charge you several thousand more dollars up front for the truck. Then they can charge you more money for speical tools and filters and oils to service it. Then they can charge you more money to rebuild it because there will be 50% more parts. and don't forget it will be more complicated for do-it-your-selfers.
Don't get mad at me its just my opionion and I would love to hear more of yours!

 

The the lower RPM spread between gears results in less wear on the clutch packs even though there are more gears. Additionally there is a mileage increase, despite your experience with one 10 year old 3 speed car. Did you try out a 6 speed in that car as well to compare the results? No.

The pure and simple fact is it does give more mileage. Thats the entire reason behind to push to either add more gears or come up with economical infinite ratio transmissions (which constantly keep the engine in the RPM sweet spot regardless of speed).

Lastly, your implication that a 6 speed is several thousand dollars more, is, well, as nicely as I can say it: far-fetched.

Automakers don't want to raise vehicle complexity and prices, it makes them much harder to sell. They won't implement higher priced technology unless there is a valid reason for it.

Vochy, I don't understand why you asked the question if you had your mind made up in advance and you're just gonna disagree with all the answers given.

 

i agree with webmaster...if you want to beotch about the 6 speed when we don't even have the option to have on yet....i'd hate to see what you'll say when you actually have one....if they all suck so bad go get a powerglide and fit that to your truck......if your logic is correct thats the best you'll ever find....

 

I know the 5-speed auto in the new GT Mustangs is much better than the old AOD.