Gear box ratio

[Dmwlking]

HI
I am after the ratio for gears in a 05 4.2t patrol manual. I am want to change diff ratio so i can lower revs at top end. IE 2000 rpm and get road speed of 105 - 110 klm. Hopefuly to improve fuel consumption.

[patch697]

Hold off on the Diff change mate, there may be another option.... You can get in touch with Marks 4x4 adapters (you'll find them listed in our Vendors thread) & find out if they do a replacement 5th gear for your Model Patrol. They have a range of ratios for the GQ/GU's & I think this would both work out cheaper in the long run & give you the best of both worlds.

Something to consider anyway......

[97_gq_lwb]

If you look at your i.d plates it will say trans axel and then a code like hh41 or hg41 etc hg41 means h233 diffs with 4.1 gear ratio hh 41 is the h260 larger diff with 4.1 ratio etc.
But the gear for the box sounds like a much cheaper and easier way to go about it.

[nissannewby]

Could you give us some more info. Tyres, lift etc. The best RPM for fuel economy isnt necessarily a lower one. Although your rpm is lower the engine may actually be under more load requiring more fuel. You need to have a the engine at a no load speed. For example most newer cars are geared for this so say 3rd gear at 60km/hr the engine is at between 2500-2800rpm this is when it will use the least amount of fuel while in driving conditions.

[Dmwlking]

thanks patch697. The gear ratio from mark adpters are perfect and cheaper.
I work out that the best fuel consumption is at 2000 -2100 rpm. for my 4.2td. Getting the new 5th gear will give me 108 klm at 2000rpm.
Thanks for all the help.
Once i get the new 5 th gear i update you. but first i have get it passed by the war office.