Is there any particular reason why you wish to upgrade?

 

You would need to do a bit more research. Just because a gearbox has 6 gears doesn't necessarily mean the extra gear will have a higher ratio than the highest gear in a 5-speed. Plus the cars ECU will be mapped differently and as far as I am aware the drive-train is different. Also the revrse light switch layout is different.

Overall the 5-speed gearboxes are more durable and reliable.

Sadly it's not a straight forward switch.

 

6 speed autos tend to have quicker changes than 5 speeds IE change up quicker as has been said its not the amount of gears but the diff ratio that will make the biggest difference.

I drove a 307 6 speed hdi recently and i found the diff ratio was so tall that you could not even use 6th gear unless breaking the motorway speed limit watching the trip computer it was clear economy was best in 5th !!

The tallest diff is what you need if you have a tall diff a 3 speed auto would do

 

Madnoel, I find that at the highway speeds I cruise at (130km/h to 140km/h) to my ear, the engine sounds like its reving excessively high for the speed being maintained. I love the car, but have always thought an overdrive gear would make the car more comfortable at speeds 130km/h -160km/h

Regards

 

Thank you kindly for the advice Madnoel, I should maybe speak to one of the local Renault breakers. Hopefully they have some specs on the final drive ratio ect. and which gearbox could give me a higher final drive. Very good points you make though.
I wish there was more aftermarket parts available. I have searched the internet high and low for a replacement gear set for the existing 5 speed to widen the gear spacing(like the ones available for certain japanese manufacturered cars) but nothing available :/

 

Mr Espace, thanks so much for the input. Your point about an altered diff ratio would actually solve the problem im having(or what I perceive anyway)
Im guessing originally cars seemingly short gearing was configured the way it is for optimal responsiveness and fuel economy for its capacity(ie making the engine feel more responsive than it really is) Just a guess.

Doing a little more research, I have found that the gearbox that is currently in the car is the JH3 142 5 speed which seems to have been standard for the Megane 1.6 (2003-2008 models). Perhaps someone with a little more product specific knowledge in terms of specifications of the various JH3 gearbox's could advise on a differential upgrade that would give me a higher gear ratio for this gearbox? Or possibly an aftermarket Differential gear set that could be purchased?

 

Old thread, but what was the fibal verdict?