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Hi, I have been driving a manual for only 4 months (the Fiat 1.6Petra). I was told that driving in 5th gear will give me the best FE. I have observed that when i drive in the 4th gear my tacho reads 25rpms at speeds of 80-100. If I put it into the 5th gear, the rpm's go up to 30 and their is more noise. Am I not getting into the 5th gear or what i don';t understand, I thought at the 5th gear I should get lower rpms at higher speeds. Can anyone explain htis to me. Also, I mostly avoid driving in the 5th gear, beacuse I still not comfortable shifting down gears due to traffic conditions.

Do you notice a sudden jerk which slows down the car for a brief moment while shifting from 4th to 5th?

You must be going into third instead of 5th.

quite likely,
In petra, the throw to the left while shifting to 5th is pretty large

No I don't notice a sudden jerk, yes I thought I might be getting into the 3rd, but usually from the 4th to the 3rd is pretty staright, whereas, I try and shift the gear to the right and then upward for the 5th. Anyway maybe I will try it a couple more times, as it si I am happy that with AC the petra is still giving me 10KMS/L driving mostly in the 4th on the highway and in the 3rd on the streets.

NO offense but do you know how to shift into 5th gear in the petra.cos you need to lift the ring around the gear to shift into 5th.if you dont lift it and still move it to slot into 5th,it might seem that its gone into 5th but actually it slots into the third gear.

Is Petra's gear mechanism different from Palio's? Atleast in Palio, you do not need to lift the ring to shift to 5th. To shift to reverse, you need to.

I never used the ring to shift to 5th in my petra. ring is only meant for reverse gear.

cheers

well in siena you have too ......or maybe i hv been doing it wrong all the time:Shockked:
ok il check,will just go for a drive:)

Whats the ring we are talking about here??

No, you dont have to lift the ring for 5th in Siena.. Its only for reverse..

There is ring below the gear knob, on the gear lever, that needs to be lifted with your finger to slot gear into reverse.. Used to be there on the Cielo too, but the reverse gear position was different

You are correct. To my mind, you should not lift the ring to move to fifth. Infact, you should move the lever towards you (driver) in the neutral position and slide it quickly upwards.

For engagement into reverse gear, as a measure of fool proofing ( Japanese call this as Poka- Yoke) it is provided to stop any inadvertant engagement into fourth gear.

Plase correct me if iam wrong

The problem is that yu might be going to 3rd gear instead of 5th

Yes, if it was 3rd you should have felt a jerk and needle would have raced to 3000+ rpm. And like many others have pointed out, you don't need to lift the ring; but bringing it to neutral, moving slightly to right and then small push upwards would have (normally) put you in the 5th. If you have rarely used the 5th gear, there is good chance that it is tight(relatively) and instead 5th it slots into 3rd.
And regarding mileage, I feel 10 is low for a mix of highway and city, it should be around 12-13. I am getting 11 in city with 50% AC. And last time it was 13because of one Mysore trip.

HI, Yeah I was not getting it into the 5th. Cause I tried a couple more times and when it slots into the 5th correctly, then the rpm remains around 20 at speeds of 80-100:) So Ijust have to get it right. Yes I know I should aim for better FE. Hopefully now I will. Thanks for all your replies. BTW on the petra only the reverse gaers needs the ring to be lifted. Yeah although technically I said 4 months, it's been only 2months since I started driving regularly. And after reading the technical stuff on this site, I just hope I have not damaged the gear box too much-while I have been driving these past 4 months.