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Re: Diff ratios

Posted: 10 Mar 2017 12:30
by Wilkie
Hi Dave that diff its not the same as the 4.5..the 4.5 has a flatter surface at the bottom . I think its to give more ground clearance :think: :think: :think:

Re: Diff ratios

Posted: 10 Mar 2017 16:01
by davidvdm
Nissan probably eventually did what a lot of Aussie guys do with the H260. They cut the bottom of the pumpkin and weld a piece of flat bar across it. That way you can evidently score about 1,5" ground clearance as the pumpkin is way bigger than it needs to be to clear all the internals. I have not had it open myself, or will even know where to start with that type of mod, so can't verify that it's possible with this one.

I'm just repeating what I have read on overseas forums.

Re: Diff ratios

Posted: 01 Sep 2017 12:23
by Alex Roux
hugejp wrote:Hope this helps...
http://www.patrol4x4.co.za/viewtopic.ph ... diff+ratio

I only realised this today, but can someone please solve this riddle for me?

Why its it so that the Patrol petrol manual (the rare GL in SA) uses a diff ratio of 1: 4.375 while the auto (GRX) uses the 1:3.5?
I was always under the impression that most of the Y60 and Y61 Patrols had pretty much the same ratios in the main gear boxes and that only the diff ratios differ (no pun intended).
The ridiculously slow 1:4.625 apart, the two 4.8 models seem to have diff ratios on the opposite sides of the spectrum.

Interestingly, the Cruiser 100/105 series have a similar set-up.
I.e. manual on slow diffs (1:4.3) and auto on fast (1:3.9).

Re: Diff ratios

Posted: 01 Sep 2017 15:12
by Peter Connan
I think there may be two factors at work here:
1) The torque converter allows the use of a "faster" diff.
2) I think there may be an assumption that the GL is more likely to work hard, while the GRX is more likely to be used as a cruiser?

Re: Diff ratios

Posted: 01 Sep 2017 15:38
by Wilkie
Alex i cant believe what differnce it makes on a 4.5L if you go from a 4.1-1 to a 4.375-1 ratio..
It feels like i have gained about 40H/P more :thumbup: :thumbup: :thumbup:

Re: Diff ratios

Posted: 01 Sep 2017 16:21
by Alex Roux
Wilkie wrote:Alex i cant believe what differnce it makes on a 4.5L if you go from a 4.1-1 to a 4.375-1 ratio..
It feels like i have gained about 40H/P more :thumbup: :thumbup: :thumbup:
Hi Errol

I have the option to convert Skilpad's 1:3.9 to 1:4.375
The crawl speed is too fast in my view at the moment. The above may explain it.

If I change to 1:4.375, my only concern is what the rev count will be at 120 km/h and whether it will not be too high.

Can anyone confirm if the manual box of the GQ is the same or close enough to that of the 4.8 GL?

Re: Diff ratios

Posted: 04 Sep 2017 11:49
by davidvdm
Bash the ratios into a spread sheet and see what you get, especially for the low range stuff. Very interesting to see how even the tires affects your crawling speed.

Re: Diff ratios

Posted: 06 Sep 2017 09:01
by davidvdm
Not sure the forum can do this, but I am trying to attach my spreadsheet I created for working out some ratios and speeds for myself. Maybe can work for guys with some changes to suite the Patrol.
Gear ratio calcs.xlsx
(13.81 KiB) Downloaded 312 times

Re: Diff ratios

Posted: 06 Sep 2017 09:26
by Wilkie
Alex Roux wrote:
Wilkie wrote:Alex i cant believe what differnce it makes on a 4.5L if you go from a 4.1-1 to a 4.375-1 ratio..
It feels like i have gained about 40H/P more :thumbup: :thumbup: :thumbup:
Hi Errol

I have the option to convert Skilpad's 1:3.9 to 1:4.375
The crawl speed is too fast in my view at the moment. The above may explain it.

If I change to 1:4.375, my only concern is what the rev count will be at 120 km/h and whether it will not be too high.

Can anyone confirm if the manual box of the GQ is the same or close enough to that of the 4.8 GL?
Alex my Patrol runs at 3000rpm doing true 130km/h

Re: Diff ratios

Posted: 06 Sep 2017 09:56
by SJC
Wilkie wrote:
Alex Roux wrote:
Wilkie wrote:Alex i cant believe what differnce it makes on a 4.5L if you go from a 4.1-1 to a 4.375-1 ratio..
It feels like i have gained about 40H/P more :thumbup: :thumbup: :thumbup:
Hi Errol

I have the option to convert Skilpad's 1:3.9 to 1:4.375
The crawl speed is too fast in my view at the moment. The above may explain it.

If I change to 1:4.375, my only concern is what the rev count will be at 120 km/h and whether it will not be too high.

Can anyone confirm if the manual box of the GQ is the same or close enough to that of the 4.8 GL?
Alex my Patrol runs at 3000rpm doing true 130km/h
Op watse grote bande: 31"(265/70r16) ?