4.5L with 35's fuel consumption and gearing

[rb30e]

I ve seen a patrol I'm interested in 4.5l petrol, had one before, they are thirsty i know this. This one if for play only and good bang for bucks. My old one had 285's and cruised at 100 at about 2200rpm from memory. I'm thinking with 35's and stock gearing this thing is going to be reving far too low, a slug and drink the juice like nothing else. Read about people chainging ratios etc and the calculators from what I'm told are not so accurate. Can anyone give me an idea what I would expect fuel consumption and rpm wise. Thanks.

[jay see]

I ve seen a patrol I'm interested in 4.5l petrol, had one before, they are thirsty i know this. This one if for play only and good bang for bucks. My old one had 285's and cruised at 100 at about 2200rpm from memory. I'm thinking with 35's and stock gearing this thing is going to be reving far too low, a slug and drink the juice like nothing else. Read about people chainging ratios etc and the calculators from what I'm told are not so accurate. Can anyone give me an idea what I would expect fuel consumption and rpm wise. Thanks.

Won't be able to help with fuel consumption as l'm on gas, but I run at about 1600rpm with 3.9 and auto trans @100.

[jff45]

Mine runs at 1850 rpm with 3.9 and stock tyres with auto TC locked.

It just does it much easier now and drinks a lot less.. :)

[BigRAWesty]

So by the sounds of it you possibly will have 3.9 diffs from above comments.
To run 35's and get it close to stock gearing your be looking at a set of 4.33 ratio diffs.
A set of 4.1 diffs will get you half way.

But..
I recently sold a set of diffs to a bloke who has a td42 turbo auto and with the stock gearing on 31" tyres he was around 1900 rpm at 100 and could not get below 16L/100k.
He threw in a set of 4.6 ratio diffs so he was now doing 86-87km at 1900 rpm and 100 up around the 2150-2200 rpm and from his initial cruze he got a staggering 11L/100k!!!!!
Now yes the engine if reving more but it's now in its peak zone and the engine is working less harder for the same outcome.

So I'm now regretting selling them as this was my plan lol..

[rb30e]

So by the sounds of it you possibly will have 3.9 diffs from above comments.
To run 35's and get it close to stock gearing your be looking at a set of 4.33 ratio diffs.
A set of 4.1 diffs will get you half way.

But..
I recently sold a set of diffs to a bloke who has a td42 turbo auto and with the stock gearing on 31" tyres he was around 1900 rpm at 100 and could not get below 16L/100k.
He threw in a set of 4.6 ratio diffs so he was now doing 86-87km at 1900 rpm and 100 up around the 2150-2200 rpm and from his initial cruze he got a staggering 11L/100k!!!!!
Now yes the engine if reving more but it's now in its peak zone and the engine is working less harder for the same outcome.

So I'm now regretting selling them as this was my plan lol..


Cool thanks for that.

Just trying to remember where the sweet spot rpm/consumption wise is on these things.

I remember trying to keep mine around 2000rpm for best fuel consumption. But that's doing bout 90kph with 285's and stock 3.9 auto ratio.

35's are considerably higher diameter, if a set of 4.33's brings it closer to stock. I'm wondering where the 4.625 would help it to perform. Clearly it would have more go but if cruising at fwy speeds am I going to be running the rpm too high and sucking the juice? Or cruise well at 120kph?

I Tow cars and boats occasionally too.

[BigRAWesty]

Cool thanks for that.

Just trying to remember where the sweet spot rpm/consumption wise is on these things.

I remember trying to keep mine around 2000rpm for best fuel consumption. But that's doing bout 90kph with 285's and stock 3.9 auto ratio.

35's are considerably higher diameter, if a set of 4.33's brings it closer to stock. I'm wondering where the 4.625 would help it to perform. Clearly it would have more go but if cruising at fwy speeds am I going to be running the rpm too high and sucking the juice? Or cruise well at 120kph?

I Tow cars and boats occasionally too.
Yes this was exactly my worries to.. would the extra rpm hurt the fuel usage??
It certainly has helped the bloke who bought my over speced diffs and he is over the moon..
But that's a td42 turbo. Wether you'll get the same with the tb42 I'm unsure..