Guys, I've red here and there that one can gain in m.p.g, if the tranny is on 3 for around town driving.

My question is regarding the possibility to shift from 3 to D, and from D to 3, while driving, when traffic either speeds up or downto over or under45 m.p.h???

In short, can I shift while rolling ????

 

Sure you can. You can even shift to a gear that is beyond its rpm and speed limit. The vehicle won’t let it actually drop into that gear until the speed & rpm's are "acceptable". Of course that means if you put it into 3rd at say.. 75mph when you do actually slow down enough for the tranny to drop to that gear the rpms will be close to redline.

Best bet, don't shift into a gear that is beyond its efficiency range ;-)

 

Thanks for the info. I just know that these tranny can be pretty picky and fragile, and I didn't want to try something to hurt it in any way.

 

The ZF tranny is not fragile by any means. if you want to get a little beter gas mileage, leave it in 3rd. and let the ECU do it's job.

 

Will do, thanks.

 

That still doesn't make since to me... why would you want the vehicle to be revving higher than it would if you kept it in D??

by 30-35 mph it's already revving higher than it would if I shifted it into D... once I do that, the rpms are alot lower...

how would the ECU "take care of it"? also.. when you left go of the accelerator at 40mph in 3, there is a big backlash... more than what is normal on D.....

 

This is for in town stop and go driving. If you are keeping steady above 40MPH, this wouldn't be for you, but for hitting tons of stoplights, not letting the tranny shift into fourth for a few seconds and then back down again does save fuel....

 

oh! ok! I got it.. yeah.. I don't live near stop and go traffic like that.. and even if there is.. I'm still the one speeding around all the traffic.

ok! thanks for clearing that up for me!!


John-Robert

 

Speeding around all the traffic will kill your MPG.