LT95 ratio change.

**D110V8D** · 15th December 2014, 11:29 AM

Hi all,

I'm looking for opinions on a potential ratio change for my 110.

Vehicle is currently undergoing a transplant of 4.6 EFI and runs the standard LT95 4 speed box with 1.3362:1 ratio (13C05368A serial number). Vehicle also runs 33 inch tyres and normal 3.54 diff ratio's.
This box is starting to get noisy and has always needed double clutching down into 3rd however I'm fairly sure it'll soldier on for some time.

I have an early RR LT95 here which is known to be in better condition than my other one and it has 1.174:1 Ratio (35542541 B serial number).

I would like opinion's on what the drivability of this ratio change might be like in the 110 considering tyre size and that the vehicle will be being used for camping trips with a fair bit of highway km's towing camper trailer.

I've been looking at Ashcroft website ratio calculator and with these specs it's telling me at 100kph in 4th gear engine speed wil be just over 2600rpm. Is this too low? Is it likely the gearing will be too high for the torque range of the 4.6, making it feel sluggish?

Thought's?

**loanrangie** · 15th December 2014, 12:25 PM

You want a .996 gear set which i believe was fitted to the RRC with hicomp 3.5 circa 82-84 just before the LT77 was introduced.

**D110V8D** · 15th December 2014, 01:16 PM

.996 lowers it even further to just over 2200rpm in 4th at 100kph.

I'm concerned that I'll be shifting down to 3rd every 5 mins to keep it moving.

Maybe I'm too used to a worn out old 3.9 with Strombergs on it.

**101RRS** · 15th December 2014, 01:54 PM

Side question - What EFI are you putting on your 4.6?

I would have thought that the 1.174:1 ratio will be fine and even the .996 ratios will be OK. The other alternative is you could stay with your 1.3362:1 (or 1.174:1) ratio and put an O/d on the transfer case.

Garry

**isuzurover** · 15th December 2014, 02:02 PM

If an isuzu 3.9 can pull heavy 110s around on 33's and 35s with 0.996 gears then your 4.6 won't have a problem with 33's and 1.174. you may find it too low and want to swap to the 0.996.

**D110V8D** · 15th December 2014, 02:07 PM

Originally Posted by garrycol

Side question - What EFI are you putting on your 4.6?

I would have thought that the 1.174:1 ratio will be fine and even the .996 ratios will be OK. The other alternative is you could stay with your 1.3362:1 (or 1.174:1) ratio and put an O/d on the transfer case.

Garry

It's a 14CUX system but uses the 20AM maf with the RPi engineering CO adjuster thing. Also has the Torando chip suited to this set up.

Engine is 10.5:1 CR with a nice torquey cam, flowed heads and top hat liners.

My aim with the ratio question is to keep the thing quite "perky" without revving it's head off at normal highway speed. Somewhere in the middle I hope.

**Wallaby Ted** · 15th December 2014, 08:12 PM

When I had the LT95 rebuilt in the County I had them change it to a Range Rover intermediary gear (can't remember which one it was but it dropped the standard gearing by about 30%). Also upgraded to a bored and stroked 3.5 (about 4.3l) running the original Carbs. I have 235/85 tyres and the change to both engine and gearbox kept it feeling about the same with a few changes.

At the top end you don't get into 4th gear until about 70kmh (it can do 60kmh) and highway rpm is now under 2400rpm instead of 3500rpm. At the low end I probably wouldn't tow a heavy caravan and try a hill start on a steep hill without using low range, but the camper trailer I tow it's fine.

HTH

Richard

**Bearman** · 16th December 2014, 05:42 AM

I have a spare set of 0.996 gears for an LT95 if you decide to go that way.

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