HZJ 80/105 diff regearing

[Bullitt]

All;

Thinking of diff regearing.

Although having HZJ 105, guess diffs are the same, and so needs advice.

Wanna have 35x13,5x16 MT.

Considering my 105 is heavily armored- weights around 2500 kgs what diff ratio would You suggest?



4.10, 4.56, 4.88 or 5.29?



Now running 33x12,5 and this is nightmare. Cant hit 120 km/h- car is also non runable on sand and seviere terrain.

Any advice?

 

[inkpot]

All;

Thinking of diff regearing.

Although having HZJ 105, guess diffs are the same, and so needs advice.

Wanna have 35x13,5x16 MT.

Considering my 105 is heavily armored- weights around 2500 kgs what diff ratio would You suggest?



4.10, 4.56, 4.88 or 5.29?



Now running 33x12,5 and this is nightmare. Cant hit 120 km/h- car is also non runable on sand and seviere terrain.

Any advice?

What is the current/stock gear ratio?

 

[george_tlc]

1hz is hardly a power house of an engine. Pushing big diameter and wide tyres would be some serious work for that engine. No after market turbo installed I presume?

Do you need or just want big tyres??

What's the stock diff ratio of your current diffs? The petrol 80's have 4.10 in the US.

The aim to regear would be to put the HP/Torque in the sweet spot at your desired NORMAL cruising speed.

Where are you located? Oz?

cheers,
george.

 

[Bullitt]

What is the current/stock gear ratio?

Guess its 4,3

As mentioned options are:

4.10, 4.56, 4.88 or 5.29?

 

[Bullitt]

1hz is hardly a power house of an engine. Pushing big diameter and wide tyres would be some serious work for that engine. No after market turbo installed I presume?

Do you need or just want big tyres??

What's the stock diff ratio of your current diffs? The petrol 80's have 4.10 in the US.

The aim to regear would be to put the HP/Torque in the sweet spot at your desired NORMAL cruising speed.

Where are you located? Oz?

cheers,
george.

Hi!

Standard diff ration on HZJ is to be 4,3 (I guess).

This is N/A motor- am thinking of turbo OR regearing.

Actually am not a fan of boosting N/A HZJ enginee especially when considering offroad as this is reducing reliability very much.

Yes. I need a bigger tires- 33x12,5 aint enough.

Am located Europe Poland.

 

[mudgudgeon]

Standard gearing in Aus HZJ105 is 4.3.
I've run 4.1 gears and 35" tyres, with the r151f 5 speed.
4.1 is way to high geared for 35s offroad
4.3 is just about ok with 33s off road, and close to perfect on road with 33s

For 35s, 4.3s and transfer case reduction gears for low range would be pretty good for everything but really steep stuff.

I've had my HZJ105 on really deep soft sand on beaches on 35s and just aired down to 10psi, and drive slow. At 10psi on soft sand, you need to plan your turns, and start feeding in some steering 5 minutes in advance

 

[Bullitt]

Standard gearing in Aus HZJ105 is 4.3.
I've run 4.1 gears and 35" tyres, with the r151f 5 speed.
4.1 is way to high geared for 35s offroad
4.3 is just about ok with 33s off road, and close to perfect on road with 33s

For 35s, 4.3s and transfer case reduction gears for low range would be pretty good for everything but really steep stuff.

I've had my HZJ105 on really deep soft sand on beaches on 35s and just aired down to 10psi, and drive slow. At 10psi on soft sand, you need to plan your turns, and start feeding in some steering 5 minutes in advance

Well U have 105 boosted, right?

Am trying to avoid it.

Thats why thinking of regearing.

Looks like 4,88 + 25% more T case reduction would make a great difference.

According to this page:

Gear Ratio Guide - Gear and Tire Diameter Ratio

4,88 would work fine with 35's.

Having also t case reduction done would give me additional advantage on rough terrain.

What do You think?

 

[mudgudgeon]

Boosted now, but not when I had 4.1 gearing.

Do you have 5 speed trans?

You might find gearing options to suit the rear diff in the 105 a bit limited. 105 don't use the same crown and pinion as 80 series. The gears aren't interchangeable beteeen 80 and 105. Front is, but not rear

 

[Bullitt]

Boosted now, but not when I had 4.1 gearing.

Do you have 5 speed trans?

You might find gearing options to suit the rear diff in the 105 a bit limited. 105 don't use the same crown and pinion as 80 series. The gears aren't interchangeable beteeen 80 and 105. Front is, but not rear

Damn- had no idea bout the differencies.
Any idea where to get the 4,88 diff?

Yes am having 5 speed manual tranny.