301TBS
Ontario, Canada
Senior Member
Joined: 12/02/2011
View Profile
 Offline
|
I have a friend with a 2008 Ford Freestyle Awd, It's a heavy vehicle, the cvt went bad a month ago. Quote to replace it was over 6 thousand. It had been serviced regularly and never towed. Mostly hiway driving. Personally I would stay clear of them.
GM is coming out with 8 spd auto for pickups next yr.
Lawn mowers are usually hydrostatic drive like ag equipment. Different beast.
2012 Kingsport301 outside kitchen
2004 Expedition EB 5.4 3.73
Reese dual cam
|
K3WE
Missouri
Senior Member
Joined: 05/24/2005
View Profile
Offline
|
One of the best "CVTs" is the electric generator-motor set up used on train locomotives. Tried, true, dependable. Unfortunately a bit on the heavy side- although the modern hybrid cars are doing similar things with ok weight and effeciency.
|
Veebyes
Bermuda & Maryland
Senior Member
Joined: 11/24/2003
View Profile
Offline
|
Some years ago Subaru had a small car with a CVT tranny. Interesting to drive. It had alot of zip for a little car. No shifting of gears. The thing just pulled. I have a similar system on my 150cc scooter. Works well.
Boat: 32' 1996 Albin 32+2, single Cummins 315hp
40+ night per year overnighter
2007 Alpenlite 34RLR
2006 Chevy 3500 LT, CC,LB 6.6L Diesel
Ham Radio: VP9KL, IRLP node 7995
|
colliehauler
Mc Pherson KS USA
Senior Member
Joined: 01/27/2004
View Profile
|
Most UTV's use a cvt and they have trouble burning up the belt with high HP motors.
|
PUCampin
Castaic
Senior Member
Joined: 07/28/2003
View Profile
|
K3WE wrote:One of the best "CVTs" is the electric generator-motor set up used on train locomotives. Tried, true, dependable. Unfortunately a bit on the heavy side- although the modern hybrid cars are doing similar things with ok weight and effeciency.
This is actually what is called a "Series Hybrid". The prime mover is a large diesel which drives a generator, which is electricly connected to electric traction motors, which drive the axles through a single speed gear reduction. There is no mechanical connection from the diesel to the axles. The diesel rpm is changed up or down to change the amount of electricity going to the traction motors. Since electric motors have max torque at 0rpm, they are ideal for this aplication. This is not really thr same as the CVT that is being discussed. The closest example to this in the automotive world is the Chevy Volt. The gas engine is not connected to the wheels mechanically, the Volt is propelled entirely by electric motors, with power from the batteries or gas motor/generator. 
* This post was
edited 02/04/12 10:40pm by PUCampin *
2007 Expedition EL 4x4 Tow pkg
2006 Pioneer 180CK (No more PUcampin!)
Nights in 10: 15
Nights in 11: 9  Rained out, sick kids, flat broke, you name it! Bad year for campin
Me DW and the 3 in 3 
DD 6/14/06, DS  11/27/07, DD  11/11/08
|
|
|
E&J push'n wind
San Diego CA, The best climate on earth!
Senior Member
Joined: 12/21/2009
View Profile
Offline
|
BRUGG,
As many have already said, to answer your question on "how do they work?" It is a variable speed pully driven by a "silent" chain, no belts though it is called a belt. I had the oportunity to see the "drive belt" in one from a Chevy something or other that had a CVT tranny. The belt had NO rubber components at all, completely steel and the pully's are driven by the sides of the belt/chain. Seeing how it works, I wouldn't want to put any heavy loads on it.
I'd have to agree with FordSuperDuty, Nissan leads the industry with a 10 year warranty on their CVT's. DW has one on her Altima, so far 60K miles and running good W/no problems at all. You can switch the shifter to make it shift like a manual tranny, preprogrammed shift points I guess.
Wisdom is the right use of knowledge. To know is not to be wise. Many men know much, and are all the greater fools for it. There is no fool so great a fool as a knowing fool. But to know how to use knowledge is to have wisdom.
Charles Haddon Spurgeon
|
K3WE
Missouri
Senior Member
Joined: 05/24/2005
View Profile
Offline
|
PUCampin wrote:K3WE wrote:One of the best "CVTs" is the electric generator-motor set up used on train locomotives. Tried, true, dependable. Unfortunately a bit on the heavy side- although the modern hybrid cars are doing similar things with ok weight and effeciency.
This is actually what is called a "Series Hybrid". The prime mover is a large diesel which drives a generator, which is electricly connected to electric traction motors, which drive the axles through a single speed gear reduction. There is no mechanical connection from the diesel to the axles. The diesel rpm is changed up or down to change the amount of electricity going to the traction motors. Since electric motors have max torque at 0rpm, they are ideal for this aplication. This is not really thr same as the CVT that is being discussed. The closest example to this in the automotive world is the Chevy Volt. The gas engine is not connected to the wheels mechanically, the Volt is propelled entirely by electric motors, with power from the batteries or gas motor/generator.
Yes, I knew someone was going to go technical and correct me because the power is transmitted electrically instead of mechanically.
Of course, just remember that those wires on big poles are called "transmission lines"
Why?, because they transmit power just like a mechanical or hydraulic, or even Radio trasmissions transmit power from where it is made to where it is needed.
For the record, the words "mechanical only" were left out on the title, consequently, "electrical" is game for discussion as a reliable, effecient and reasonable method of having a continuously variable vehicle transmission.
|
dodge guy
Bartlett IL
Senior Member
Joined: 03/23/2004
View Profile
Offline
|
They are basically a very sophisticated snow mobile belt drive sytem!
Wife Kim 
Son Brandon 10yrs
Daughter Marissa 9yrs
Dog Shadow
07 Cherokee 32B
02 Excursion 4X4 V-10 4.30 gear Hellwig sway bar
Reese HP dualcam,Prodigy brake controller.
A bad day of camping is
better than a good day at work!
|
sc3283
St Louis
Senior Member
Joined: 01/15/2008
View Profile
Offline
|
the concept is nothing new................how many remember the "Salisbury Clutch" from the 40s???? Same concept, just more sophisticated.
04 D-Max Crew Dually
96 Monaco Dynasty 36'
|
mike4947
N. Syracuse, NY
Moderator
Joined: 08/26/2002
View Profile
Good Sam RV Club Member
Offline
|
Vauxhall used one back in the 60's. Their problem then was wearing tracks in the pullies and the "car" would stick at that point. Needless to say you don't see many Vauxhalls today.
As for the chains used they date back to the late 1890's. Originally called "silent chain". Later versions were called "hivo chain".
Got to go on a plant tour where people would hand lace up the plates on pins that made up the silent chain, and the automated (high volume) HiVo chain assembly lines.
blog.rv.net Your daily guide to the Open Road
Subscribe to the daily digest
They say you learn by your mistakes, in that case I must be a genius.
|
|
|
