What do you think about Low Range Reduction Gears

[macca]

I have a bit of a dilema, our patrols a fairly high geared and with mine do most difficult parts of tracks in low low.
Other brands do the same in low 2nd, leaving them a crawler gear for the harder stuff and good engine braking down hill.
I have been in situations where slipping the clutch and holding the revs at 2000 - 2500 is the only way to proceed.
This has not happened often but abusing the clutch like that is not a good thing.
So looking at reduction gears for the low box is raising more questions than answers, if you have a look at the spreadsheet attached it explains the possible benifits.
If you have reduction gears can you post your opinions especially the effect on different terrains.
The 65:1 would be awsome on the rocky climbs but what about the Canning Stock Route? It has 2nd gear matching the 1st in a stock set up.
Appreciate your thoughts whether you have them or not.
Cheers Macca

[growler2058]

I rekon any greater than 33" tyres ya need reduction gears. If you have an auto bloody good idea for downhill control. Im on 33's and reduction gears are on my wish list most definately

[macca]

Which set would you get?, I'm on 33's too.

[growler2058]

Wellllll eventually i want 35"s so the 85% are the way to go i rekon. Send big rig a pm if he doesnt read this thread he recently put a set in tank and is happy as a pig in poo

[macca86]

I have heard that if on 33' tyre stay to 40%ish reduction gears or if on 35' run 80%ish reduction gears depends on your main driving style if you do beach work prob only go 40%ish as you still need speed for momentum

[gec]

Me, I'd love a set of crawler gears, and I would also get the 85% and I have 33's.
:driving2:

[macca]

I have heard that if on 33' tyre stay to 40%ish reduction gears or if on 35' run 80%ish reduction gears depends on your main driving style if you do beach work prob only go 40%ish as you still need speed for momentum

mmmmmm "momentum is your friend" a mate runs a tough truck said to really consider the momentum issue. It applies in mud slippry tracks as well. Concerned about the CSR next year, climbing sand ridges could be a pain.

[growler2058]

Use high range if ya need momentum or use 4th and 5th in low

[Bigrig]

Yep, 85% Marks Adapters in mine and simply the best (bar nothing) money I've spent on the truck. You need to weigh up your style of driving mate, but I have probably twice in my life used low range on sand ... Deflated tyres and high range has seen me never bogged to this day (and I would say I've beach driven at least 40-50 times on the beach at places like Fraser, Moreton, Bribie and Stradbroke Islands, as well as Rainbow beach, Woodgate - hard packed sand there though - and Anna Bay).

In mud, low third definitely has enough momentum, and for rock crawling and down hill control, simply unbeatable.

Not saying go 85's by any means though, as it sounds like you just need "a little more" low range gearing, and if that be the case, 43% would suffice for sure - absolutely more than noticeable ...

Good luck with the decision and feel free to ask away if you think of anything else ...

[pearcey]

G`day Macca.
Don't be concerned about the CSR I did it in 08 towing a camper trailer using stock gears
Main thing on the CSR is tire pressures 18 to 24 PSI no higher. I ran 18 on the car and the trailer with no problems not 1 flat.
Run these pressures from start to finish and take your time and you will not have trouble

[macca]

Thanks guys, sort of leaning toward the 85's, they seem to step the gearbox 1 gear or very close to.
So what I do now I just have to be 1 gear higher.
Is that what you have found BigRig?
2 guys in our club have them, so I hope to have a yarn with them when we do our next trip.
I know 1 of them doesnt like the lack of momentum, but I dont know if he has run out of gears in low range. He must be fair hooting!!!!
Still researching...

[macca]

G`day Macca.
Don't be concerned about the CSR I did it in 08 towing a camper trailer using stock gears
Main thing on the CSR is tire pressures 18 to 24 PSI no higher. I ran 18 on the car and the trailer with no problems not 1 flat.
Run these pressures from start to finish and take your time and you will not have trouble

We crossed the Simpson in our Lux using low 2 & 3 mainly (and 16psi) so I'm guessing we would be in 3 & 4 with these reduction gears.
I am a fan of lowering tyre pressures and dont understand those who dont. Some think they are "tough???" saying I got through with out dropping a psi. If they look behind them they are more than likely damaging the track.
On that Simpson trip we got stuck once and that was trying to cross a ridge in a gear higher than we had been using, only did it to see what would happen. Climbed Big Red with 10psi not a worry in the world. That was a great trip.

[Bigrig]

Thanks guys, sort of leaning toward the 85's, they seem to step the gearbox 1 gear or very close to.
So what I do now I just have to be 1 gear higher.
Is that what you have found BigRig?
2 guys in our club have them, so I hope to have a yarn with them when we do our next trip.
I know 1 of them doesnt like the lack of momentum, but I dont know if he has run out of gears in low range. He must be fair hooting!!!!
Still researching...

Hmmm ... I'd say 85% is more like two gears at least mate. Will try to dig out the video I did, but I let the truck 'run away' in 4 low first gear on a hill at Landcruiser park prior to getting the gears and it maxed out at around 15 Klms per hour without brakes. Did the same hill post getting the 85's put in and it maxed out at about 3-4klms per hour .... that much of a difference ...

I'm sorta thinking you might want to look into the 43's if you need to 'tour' as such in low range - my box (3 speed with overdrive) would be lucky to do 25klms in overdrive whilst in low range, and even then, the gears are whining pretty loudly (as they do) ...

[macca]

Be good to see the vid mate
That chart I attached has the 85% closer to 1 step in gearing than the 43% or have I made a blue?
2nd and 3rd are fairly close but they do get a bit further away in 4th and 5th.
Real world driving is the best result anyway.
I dont want to spend the coin and find I am revving hard in first all the time, prefer to be in 2nd and have another option available.
Maybe the 4.2's can pull well enough in 2nd with a final drive of 28.86:1, if they do then the 43% is the winner

[Bigrig]

Be good to see the vid mate
That chart I attached has the 85% closer to 1 step in gearing than the 43% or have I made a blue?
2nd and 3rd are fairly close but they do get a bit further away in 4th and 5th.
Real world driving is the best result anyway.
I dont want to spend the coin and find I am revving hard in first all the time, prefer to be in 2nd and have another option available.
Maybe the 4.2's can pull well enough in 2nd with a final drive of 28.86:1, if they do then the 43% is the winner

I'll see if I can fin it boss as it was mid last year ... a manual 5 speed will be different, Dhuck has reduction in his with a 5 speed box, so he might be able to shed light on the topic. I know he tackles most hard hills (steep and hard) in third low from memory as it is really that low ... I don't reckon he'd be able cruise at all in low ...

[88Shorty]

Could any of you guys who have reduction gears give me a rough idea of how much coin i would be looking at to get a set in my truck?
Like the rest of you i am wanting slower crawling speeds on my 35inch tyres

[macca86]

http://www.marks4wd.com/products/gearmaster/Nissan-GQ-GU-extra-low-tc-gears.htm

A handy tool to see what speeds in what gear to help work it out
http://www.apexgarage.com/tech/gear_ratios.shtml

[Ross42]

Hi Macca Have a conversion around where they use 2 transfer cases gives the best ove both worlds but you need a shortend t shaft and two high low gear shifts Ross

[macca]

http://www.marks4wd.com/products/gearmaster/Nissan-GQ-GU-extra-low-tc-gears.htm

A handy tool to see what speeds in what gear to help work it out
http://www.apexgarage.com/tech/gear_ratios.shtml

Great link, thay has really helped, thanks from the other Macca LOL

[macca]

Hi Macca Have a conversion around where they use 2 transfer cases gives the best ove both worlds but you need a shortend t shaft and two high low gear shifts Ross


Read about this mod on another forum, a bit to complicated and big for my needs.
Read something about a "lefty"? the shafts are swapped side to side?
The bloke that did it must of paid some as the installers came fro the States and did the mod at his home..... What The ????

[macca]

Ordered a set of 43% gears today, 85% are too low. Guys that have them find them a PITA on sand like Stockton Beach. So desert dunes will be the same.
They are out of stock and due to arrive next month.
They took my details and will call. Offered to prepay and they said wait till they call.
Gives the impression of a very well run business.

[growler2058]

Ordered a set of 43% gears today, 85% are too low. Guys that have them find them a PITA on sand like Stockton Beach. So desert dunes will be the same.
They are out of stock and due to arrive next month.
They took my details and will call. Offered to prepay and they said wait till they call.
Gives the impression of a very well run business.

Can i ask how much?

[macca]

Can i ask how much?

G'day Growler,
Their site says $1350.00 see what happens when they arrive, post etc

http://www.marks4wd.com/products/gearmaster/Nissan-GQ-GU-extra-low-tc-gears.htm

[pjhicks3]

I have just had some fitted, 43% reduction gears, and I have 33" tyres, Auto Gu. cost - $1950 fitted..
only thing I noticed was a very slight high pitched whine, nothing too major, and I don't think most would hear it, in fact most mud tyres would be louder, but it seems to be there none the less.
Has anyone else noticed the noise after fitting theirs?

[macca]

4th & 5th are the worst for the whine, it does say in the instructions that the low range will be louder.