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Firstly you wont strip 5th gear cruzing on light throttle at any speed....no pressure on the gear set or main shaft.

I disagree, 5th gear doesn't need throttle/load to be stripped. Being an overdrive gear it has both the engine and the road working against it so anything below 80km/h even on a flat road is going to be detrimental to it. 5th gear losing teeth because of this attitude is very common...

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There is more load....far more load through the drive train by a high factor in first compared to fifth.

Stick your car in first and hold it at 60, give a little gas, take a little off and feel the dynamics of what the car does.

Its road speed vs rpm, its the least mechanically binding gear. The only thing that could force it to break is if the gear set (fifth) is so small and weak that it cant take it. Ive never seen it happen.

Ive been cruzing in my GTR in fifth at 60 without a problem for years, infact i hold all my cars in the same way, never had a problem in any of them in regards to a lower gear.

I just pick the gear and listen to the engine to make sure its not lugging.

Yep blown quite a variety pushing power in lower gears, even took one out missing a gear once from all the force going to a lower gear, but after 27 years of street driving and track days, never a fifth gear due to breakage, bearing or mainshaft wear, yes but thats another thing all together.

Edited by GTRPSI
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I agree with GTRPSI al the way. I normally hold 60k in 5th gear but only on a flat road.. if i hear the engine lugging or something.. i always chop down.

I once had my timing increased to 18.. and, if i remember correctly, i was using more petrol - but thats only due to the fact that i had a heavy foot

But generally now that mines back to 15..

I think im sitting around 12.5-13 L/100ks

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Yeah well I have seen it happen, ALOT. 5th gear at 60km/h is silly...the difference between 5th and 4th at that speed is a mere 500rpm - not going to make a great deal of difference to fuel economy. I strongly advice against doing it. I make alot of money out of people incorrectly using 5th gear...

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A lot of confidently-held opinions here on 5th gear - but no agreement, and not much light.

Is there a technical discussion somewhere about 5th gear and its uses that might help? I've spent a lot of the last ten years driving autos (family cars etc - yes, I know), and I may be completely out of touch. I had always believed 5th gear was best for fuel economy and general wear down to about 60 or so.

On the same general subject: what's the normal spread of revs by gear in the GTS-T? Coming over from 6 cylinder autos, I was a bit panicked at first. Seemed I was hitting much higher revs than I expected at the same speeds...

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It's not so much 5th gear, it's overdrive gears...which in our cars happens to be 5th. In some gearsets (e.g. truck transmission), 5th is not an overdrive gear and is quite safe to use at speeds of 60km/h for example - but it can all come down to the engine/transmission configuration and type of car. In this case we are looking at Skylines where 5th is top gear and an overdrive.

Overdrive gears are only good for fuel economy and they put the greatest stress on the engine and themselves. As a rule of thumb, the faster you are travelling the better it is for the overdrive gear and the engine. The problem is that too many people drive manuals like autos, thinking that just because an auto changes down to top gear when cruising then they should too. But autos have a torque converter that significantly reduces the load placed on the overdrive gear - and even then most autos will not change into overdrive until over 70km/h.

As for GTS-T gearing and revs...travelling at 80 km/h in 5th usually sits you around 2000rpm from memory. Don't worry about the transition from auto to manual leaving you with higher RPM...manuals are generally geared shorter with closer ratios than automatics resulting in this. They are still generally more economical :P

But in short, save 5th for 80km/h+ on a flat road and you will be fine.

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well looks like this has gone way off topic.

my thoughts are that if you drive a manual, it is all about when you want to change gears. apart from that we would all be driving auto.(i know, also feels like we're driving the car more etc)

5th gear should only really come in to play at 80+ km/h, do you see people doing 60 in 6th gear or some GTR's? Ive never.

I know that there is only a small difference between in revs in 5th and 4th, but that tiny amount might be either in the torque range and not.

As far as fuel consumption goes, alot of people do have it set in their minds that lower revs = less petrol. But it all comes down to what stress the engine is under. Im finding that winding out the gears with very little throttle is very efficient. These cars are at home on a racetrack, their not made for plopping along at 60km/h in 5th, their engines are made to be rev'd and wound out.

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It's not so much 5th gear, it's overdrive gears...which in our cars happens to be 5th. In some gearsets (e.g. truck transmission), 5th is not an overdrive gear and is quite safe to use at speeds of 60km/h for example - but it can all come down to the engine/transmission configuration and type of car. In this case we are looking at Skylines where 5th is top gear and an overdrive.

Overdrive gears are only good for fuel economy and they put the greatest stress on the engine and themselves. As a rule of thumb, the faster you are travelling the better it is for the overdrive gear and the engine. The problem is that too many people drive manuals like autos, thinking that just because an auto changes down to top gear when cruising then they should too. But autos have a torque converter that significantly reduces the load placed on the overdrive gear - and even then most autos will not change into overdrive until over 70km/h.

As for GTS-T gearing and revs...travelling at 80 km/h in 5th usually sits you around 2000rpm from memory. Don't worry about the transition from auto to manual leaving you with higher RPM...manuals are generally geared shorter with closer ratios than automatics resulting in this. They are still generally more economical ;)

But in short, save 5th for 80km/h+ on a flat road and you will be fine.

Thanks, Birds. That's all very helpful advice. Yes, 80ks at 2000 revs in 5th seems about right. And yes, the fuel consumption so far seems pretty good. I must just learn not to worry about that tacho so much...

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lol! i drive at 60 in 5th gear all the time even 50 in 5th and the skyline loves it.

Also with the whole auto torque converter thing, my stagea lock's up the torque converter at 60km/h and the car sits at about 1500rpm so thats even worse than me driving my skyline at 60 in 5th.

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Some interesting stuff in hear.

My contributions :(

I agree with not using any gear ratio higher than 1.0 (O/D / 5th gear) to accelerate. Maybe when cruising, but to increase speed with a higher gear ratio puts a lot of strain on a few places in the drivetrain.

Rolling - roll with the trucks, notice how they take 100m to stop before a light? because moving an already rolling vehicle is alot easier than moving a stationary vehicle. Keep the car moving and time for your green light, avoid stopping where possible, even at lights. This saves a LOT of fuel, because of how the ECU monitors driving habbits.

Keeping your car in tune - I havent had my Cef long enough to experinment with this, but my example would be my daily, 1994 Maxima, its a VG30E Auto. Untuned, due for service, regular fuel and having learnt bad driving habbits, gets about 450km (65l tank), retune it, service it, 98 octane fuel, and let it learn better driving habits, and it pulls about 750-800km (65l) - not bad for a 94' V6 auto in peak hour driving, hey?

-

Yeah, its pretty hard to save fuel in high performance cars ;)

Almost impossible, you can drive nicely to work, the ECU gets half way to adjusting to that, then on the way to a mates house, you put your foot down and take off realy awesome-like, the ECU is going to think, "wtf is this bi-polar mo'fo doing???"

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Hey guys,

When i first bought my skyline, i knew that petrol consumption would be a bit higher than what i was driving around (a mirage... and yes i know).

So over the past 3/4 weeks of owning the car ive managed to decrease my fuel consumption by quite a decent amount.

So here's my tips:

1: Dont hit boost (obvious, but ill explain more further down)

2: Right fuel

3: Easier driving

4: Winding out the gears

5: Using the brakes (More about caring for your car)

Now, most of you guys would know that not hitting boost can save ALOT of petrol, but what some people dont know if more vacuum pressure can also alter consumption,

and as probably everyone knows that a turbo runs off exhaust gas. If you for example, take off from a set of lights, and get top 60km/h in 4 or 5 seconds, you are going to be using more petrol than someone who would take 7 or 8 seconds.

On that note also, winding out the gears can also save you some dosh. Alot of people tend to think lower revs = less fuel used. This may be arguable but i definitely think it doesn't.

If you slowly wind out the gears to say 4500 RPM's, then due to the little amount throttle position and little amount of exhaust gas and pressure being produce, you can make it to 4500RPM without even hitting boost. Yes it will take you a little longer to get up to the speed limit, but who cares, most people take between 7 or 8 seconds to get to the speed limit. Tried to avoid stop start driving (i know this is a obvious one, but it makes a difference)

Right fuel can be one of the big winners. Even thought most of us would own similar skylines, each skyline is different in the tiniest possible way. And the difference in which petrol can make a BIG DIFFERENCE. If your mates recommend Caltex's Vortex 98, then give it a go, but dont stick with it if your not gaining anything. Its a matter of finding the right petrol that your car will like, not what a mate may recommend. Find the petrol that your car likes, and it does make a significant difference.

When slowing down, alot of people tend to using engine braking to do most of their braking. (that was a sh*t sentence lol)

Whilst this is also arguable, this is more a tip for looking after your car. What ever way you slow down, your wearing out parts of the car. People who using engine brakng are actually wearing down their engine and gearbox. Same with using the brakes, but when you look at it, a new set of brakes is alot cheaper than a new gearbox or tranny.

PLEASE NOTE:

These are my own tips and tricks i have been using, and since ive bought the car to now, ive manged to drop it from 12.5L/100km to 10L/100kms. If people do disagree with what ive said then yes do please speak up, but ive taken the time to try and provide some tips for people who are trying to save some cash.

Buckets out.

mate firstly i dont want to sound rude, but basically to save 2.5ltrs of fuel per 100kms, your advice is to drive like miss daisy. they are good sound tips, but they honestly defeat the purpose of owning a high performance vehicle. if you want to save on fuel and putt around town all day, maybe you should consider going back to the mirage again?

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mate firstly i dont want to sound rude, but basically to save 2.5ltrs of fuel per 100kms, your advice is to drive like miss daisy. they are good sound tips, but they honestly defeat the purpose of owning a high performance vehicle. if you want to save on fuel and putt around town all day, maybe you should consider going back to the mirage again?

'I don't want to sound rude.' LOL. Seems you succeeded mightily in achieving what apparently wasn't your object...

As an aside, I actually found the 80kph for 5th gear advice very helpful.

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Yes, but if your driving through traffic in the city, your not going to be taking advantage of this "great performance, strong chasis, and tight handling", so why not baby it a bit, and save some money to spend on mods or more petrol for longer weekend drives.

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'I don't want to sound rude.' LOL. Seems you succeeded mightily in achieving what apparently wasn't your object...

As an aside, I actually found the 80kph for 5th gear advice very helpful.

fair call, it didnt really come out how i ment it to. basically what i was getting at was that these tips revolve around "driving style" somewhat, for me, and most other skyline owners, the skyline is a car centered around great performance, strong chasis, and tight handling. like most skyline owners i have spent thousands of dollars emphasizing these key points of my car. i find that these tips on reducing fuel consumption are great tips, and very well thought out, but in my opinion they take the essence out of what it is to drive a skyline.

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my r33 had no issues at all in 5th @60kmh/ providing its flat ground. my bro inlaws r34 drives very nicely cruising in 5th @ 60kmh. both very smooth and no lugging. ive had mine for 7 years now never an issue, or with any of my other cars, particularly my work van which saw alot of kms on the road hehe

ben...

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Yes, but if your driving through traffic in the city, your not going to be taking advantage of this "great performance, strong chasis, and tight handling", so why not baby it a bit, and save some money to spend on mods or more petrol for longer weekend drives.

cheers sneakey pete! :rofl:

fair call, it didnt really come out how i ment it to. basically what i was getting at was that these tips revolve around "driving style" somewhat, for me, and most other skyline owners, the skyline is a car centered around great performance, strong chasis, and tight handling. like most skyline owners i have spent thousands of dollars emphasizing these key points of my car. i find that these tips on reducing fuel consumption are great tips, and very well thought out, but in my opinion they take the essence out of what it is to drive a skyline.

I know your not trying to be rude, but look at it this way...

Petrol prices are going up, and nothing is really gonna stop it, we are running out of curde oil and thats how its gonna be, so for the time being why not squeeze your pennies a bit more.

And when i mention on saving fuel, i didnt mean drive like miss daisy, i mean you can do that, hell i even do it, coz it works on fuel, im a uni student, so im finding any way i can to get the most bang for my buck. And if your read my topic properly, it says winding out the gears, you can still have fun in everyday driving just dont fang it all the time.

Ive spent two years saving for a liner, on a sh*t all amouny of money per week, im not gonna go and cut myself short by hammering the car around everywhere and then having a liner and not being able to use it.

I see it as: You drive like a granny through the week = more fuel for a spirted weekend drive, or whatever floats your boat.

And as i also said, some people may disagree with me on what i've said, i took the time to think about all these and write it all down for all those owner's who dont have such great petrol consumption. If you happy with the fuel consumption of your liner, then just dis-reguard my topic and keep on driving how you wanna drive.

Im hopefully providing help, not causing arguments...

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mate firstly i dont want to sound rude, but basically to save 2.5ltrs of fuel per 100kms, your advice is to drive like miss daisy. they are good sound tips, but they honestly defeat the purpose of owning a high performance vehicle. if you want to save on fuel and putt around town all day, maybe you should consider going back to the mirage again?

My take on it is that if driving sedately will not get me to the destination much slower (eg you're in traffic, so why floor it) then you're avoiding extra emissions and money spent on fuel. Plus, when you DO floor it it's a bigger smile-getter than if you just floor it everywhere and are used to the power level. I love putting my foot down after driving gently for a bit and getting the "holy shit my car's quick" sensation :)

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My take on it is that if driving sedately will not get me to the destination much slower (eg you're in traffic, so why floor it) then you're avoiding extra emissions and money spent on fuel. Plus, when you DO floor it it's a bigger smile-getter than if you just floor it everywhere and are used to the power level. I love putting my foot down after driving gently for a bit and getting the "holy shit my car's quick" sensation ;)

quoted for truth.

love that feeling!

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my r33 had no issues at all in 5th @60kmh/ providing its flat ground. my bro inlaws r34 drives very nicely cruising in 5th @ 60kmh. both very smooth and no lugging. ive had mine for 7 years now never an issue, or with any of my other cars, particularly my work van which saw alot of kms on the road hehe

ben...

What you feel and what is happening with the gearbox are two very different things. Everyone I've seen blow 5th gear gets such a surprise when it happens. "I was just driving along the road...not towing anything, no heavy weight...it was flat...and then bang...I lost 5th". It doesn't happen to everyone, just like not everyone who goes to a casino is guaranteed to lose their money...but why push the chances when the experts have told you how it is?

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