Stepspeed/Steptronic question

Busboy · 21st April 2018, 12:12

Although my question Is not related to 75/ZT's, I wonder if anyone could direct me to where I can find out the Fuel consumption of cars fitted with this type of Autobox, as I would imagine they could be quite heavy on fuel due to the nature of the CVT system. Any info please folks?

coolguy · 21st April 2018, 12:24

I have owned a couple of 45s 1.8 litre with the cvt box. They are heavier on fuel in traffic and on local runs, but much better on a good run. I think if you look up any particular car for sale on Autotrader, the fuel consumption figures from the manufacturer are shown at the end (if you believe them!)

fandango151 · 21st April 2018, 19:21

You will find a CVT is better than a conventional auto in many cases but all model dependent. The reason is they use a computer controlled clutch rather than torque converter generally so the slippage is reduced.

Downside is to create creep they slip the clutch so imho less reliable (think in drive whilst not moving). CVT in theory should be better as it's not stepped so there are numerous combinations not 1,2,3,4 etc.

In reality expect 10-20 % loss on mpg Vs manual figures on any auto with anything better being a bonus. Cvts actually trump conventional autos for mpg

Busboy · 22nd April 2018, 07:06

Quote:

Originally Posted by fandango151

You will find a CVT is better than a conventional auto in many cases but all model dependent. The reason is they use a computer controlled clutch rather than torque converter generally so the slippage is reduced.

Downside is to create creep they slip the clutch so imho less reliable (think in drive whilst not moving). CVT in theory should be better as it's not stepped so there are numerous combinations not 1,2,3,4 etc.

In reality expect 10-20 % loss on mpg Vs manual figures on any auto with anything better being a bonus. Cvts actually trump conventional autos for mpg

Thanks for the above interesting reply, I have always had an interest in autos and have owned Rootes Easidrive examples in the past, and they were not much more to run than the manual version due to the Magnificent powder coupling, which did not suffer the heat loss that a fluid coupling does.

I currently have a CDTi auto with the superb Jatco box, but was thinking of getting the low mileage 25 that is on e-bay for my wife, but I remember that when she had a CVT Micra auto, the one litre engine struggled to return 30 mpg around town, so I would therefore assume that a 1600cc 25 stepronic would not be that economical either.

I'm giving the Rover 25 a miss for that reason, It would probably be much better on longer runs. I have also heard some horror stories on the reliability of the Stepronic box

fandango151 · 22nd April 2018, 13:44

For me personally they are a no no. A CVT with a torque converter (I think some minis did it not sure) would be ideal. Other than that a conventional auto which is becoming a rare thing with the demands on fuel economy and cheapness to produce Vs a conventional.

The jatco is fine but there are even better things out there - I think the compactness of the unit is a hindrance tbh. My 300c has a Merc derived box and in truth the 3.5 is as economical as my 2.5 75 - gut feel is the box is the reason.

21st April 2018, 12:12	#1
Busboy Loves to post 75 tourer (facelift) 2.0 CDTi Join Date: Sep 2014 Location: Gravesend Posts: 479 Thanks: 456 Thanked 55 Times in 39 Posts	Stepspeed/Steptronic question Although my question Is not related to 75/ZT's, I wonder if anyone could direct me to where I can find out the Fuel consumption of cars fitted with this type of Autobox, as I would imagine they could be quite heavy on fuel due to the nature of the CVT system. Any info please folks? __________________ One of the best of the last from the last of the best! Produced on Valentine's day 2005 - 8 weeks before the end.

21st April 2018, 19:21	#3
fandango151 Loves to post Rover 75 Join Date: Jul 2015 Location: Tamworth Posts: 291 Thanks: 2 Thanked 72 Times in 65 Posts	You will find a CVT is better than a conventional auto in many cases but all model dependent. The reason is they use a computer controlled clutch rather than torque converter generally so the slippage is reduced. Downside is to create creep they slip the clutch so imho less reliable (think in drive whilst not moving). CVT in theory should be better as it's not stepped so there are numerous combinations not 1,2,3,4 etc. In reality expect 10-20 % loss on mpg Vs manual figures on any auto with anything better being a bonus. Cvts actually trump conventional autos for mpg Last edited by fandango151; 21st April 2018 at 19:39..

21st April 2018, 12:24	#2
coolguy Coolguy Rover 75 CDT Tourer Auto, Rover 75 2.0 Connoisseur Auto, MG ZT 2.5 Auto and MG ZT Cdti Auto (Monogra Join Date: Nov 2009 Location: Finedon Posts: 1,897 Thanks: 933 Thanked 638 Times in 430 Posts	I have owned a couple of 45s 1.8 litre with the cvt box. They are heavier on fuel in traffic and on local runs, but much better on a good run. I think if you look up any particular car for sale on Autotrader, the fuel consumption figures from the manufacturer are shown at the end (if you believe them!)

22nd April 2018, 13:44	#5
fandango151 Loves to post Rover 75 Join Date: Jul 2015 Location: Tamworth Posts: 291 Thanks: 2 Thanked 72 Times in 65 Posts	For me personally they are a no no. A CVT with a torque converter (I think some minis did it not sure) would be ideal. Other than that a conventional auto which is becoming a rare thing with the demands on fuel economy and cheapness to produce Vs a conventional. The jatco is fine but there are even better things out there - I think the compactness of the unit is a hindrance tbh. My 300c has a Merc derived box and in truth the 3.5 is as economical as my 2.5 75 - gut feel is the box is the reason.